WO2010124590A1 - Motor - Google Patents

Abstract

A motor comprises a motor body (501), a controller and an electromagnetic sensor. The electromagnetic sensor is used for sensing rotation of a motor shaft, and outputs sensed voltage signals to the controller. The rotation angle or the position of the motor shaft is obtained by the controller. Thus accurate control of the motor is realized. The number of magnet poles involved in the electromagnetic sensor used in the motor is independent of the number of rotor magnet poles of the motor. Thus the match between the motor and the electromagnetic sensor is flexiable. Because the sensor is applied to the motor, control accuracy, response speed of the system, and reliability are improved, and production cost is reduced.

Description

 Electric motor

Technical field

 The present invention relates to an electric motor, and more particularly to a control electric motor for precise position control. Background technique

 The electric motor is a very widely used power source in the industrial field, and the control of the electric motor will directly affect the operation of the entire system. Therefore, the control system of the electric motor has also been widely concerned.

 There are many types of motors. According to different classification standards, motors can be divided into asynchronous motors and synchronous motors; AC motors and DC motors. In some existing systems, it is necessary to precisely control the position, rotation speed, and the like of the motor, and therefore, a servo motor has appeared. This type of motor is combined with a controller and an encoder to achieve closed loop control of the motor. Due to its high response characteristics and wide speed range, it has received extensive attention from industrial and agricultural production. The accuracy of the position detector used on the output shaft for detecting the position of the motor directly affects the speed control and positioning accuracy of the system.

 At present, the position detecting sensor mainly uses an encoder. The current common method is to install a photoelectric encoder on the motor to transmit the angle information to the controller through the cable.

 When the incremental encoder shaft rotates, the grating disk rotates, and the light emitted by the light-emitting element is cut by the grating disk, and the slit of the indicating grating is cut into intermittent light to be received by the receiving component, and the corresponding pulse signal is output, and the rotation direction and the number of pulses are required. This is achieved by means of a decision circuit and a counter. The starting point of the counting can be set arbitrarily. When the rotary encoder rotates, the pulse is output. The position is memorized by the internal memory of the counting device, and the pulse cannot be lost during the working process. Otherwise, the zero point of the counting device will be lost. Offset, and nowhere to know.

 In order to solve this problem, an absolute encoder has appeared. The absolute encoder outputs a code that corresponds to the position one by one. The change in the size of the code can determine the direction of rotation and the current position of the rotor. In this way, the reliability of the data is greatly improved, and the absolute encoder has been increasingly applied to various industrial systems for angle, length measurement and position control. However, there are some insurmountable shortcomings in the photoelectric encoder: The photoelectric encoder is made of glass material through the scribe line, which is not strong against vibration and impact, and is not suitable for harsh environments such as dust and condensation, and has complicated structure and positioning assembly. There is a limit to the line spacing. To increase the resolution, the code wheel must be increased, making it difficult to miniaturize. High assembly accuracy must be ensured in production, which directly affects production efficiency and ultimately affects product cost.

 Due to the problems of the above photoelectric encoder, a magnetoelectric encoder for use on a motor has appeared, which mainly includes a magnetic steel, a magnetic induction element and a signal processing circuit, and the magnetic steel changes with the rotation of the shaft of the motor. The magnetic field, the magnetic induction element senses the changed magnetic field, converts the magnetic signal into an electrical signal output to the signal processing circuit, and the signal processing circuit processes the electrical signal into an angular signal output. However, for a DC brushless motor, the magnetic pole of the magnet used in the magneto-electric encoder is adapted to the number of magnetic poles of the DC brushless motor. DC brushless motors with different pole counts can be used in conjunction with their compatible encoders. Therefore, such magneto-electric encoders have poor versatility.

 In addition, the current motor generally uses the cable method to transmit the position information to the controller's CPU, but the communication process is susceptible to electromagnetic noise and causes information errors, and there is communication lag, which cannot reflect the current motor rotor position information in real time. Thereby affecting the control effect of the entire system.

Moreover, the traditional motor design pursues the completion and implementation of a single target, but in the need to complete more tasks, different motors must be selected for different tasks. For example, if high load and high speed are required in task 1, it is necessary to select a motor with high torque and high speed. Task 2 requires that the load has a moderately low speed, so that the motor selected in task one is no longer suitable for the task. Second, the working conditions, you need to choose another motor, which will cause waste. Summary of the invention

 The technical problem to be solved by the present invention is that the present invention proposes an electric motor having a new magnetoelectric sensor, thereby achieving low cost, improving system reliability, and improving system response speed.

In order to solve the above problems, the present invention provides an electric motor including a motor body, a controller, and a magnetoelectric sensor for sensing rotation of a motor shaft and transmitting the sensed voltage signal to The controller obtains an angle or a position of the rotation of the motor shaft by the processing of the controller, thereby realizing precise control of the motor; wherein the magnetoelectric sensor comprises a rotor and a stator that sleeves the rotor inside, the rotor includes a magnetic steel ring and a second magnetic steel ring; the first magnetic steel ring and the second magnetic steel ring are respectively fixed on an output shaft of the motor, and the first magnetic steel ring is uniformly magnetized to N [ N<= 2 ⁿ (n = 0, 1, 2 - n) ] to the magnetic pole, and the polarities of the adjacent two poles are opposite; the total number of magnetic poles of the second magnetic steel ring is N, and the magnetic order is determined according to a specific magnetic sequence algorithm; On the stator, corresponding to the first magnetic steel ring, the same circumference of the center of the first magnetic steel ring is provided with m (m is an integral multiple of 2 or 3) magnetic induction elements distributed at an angle; corresponding to the first Two magnetic steel ring, with a second magnetic steel ring The magnetic center of the center of the center is provided with n (n = 0, 1, 2, ..., 1) magnetic induction elements distributed at an angle; when the rotor rotates relative to the stator, the magnetic sensing element will sense The magnetic signal is converted into a voltage signal, and the voltage signal is output to the controller.

 Preferably, the angle between adjacent two magnetic sensing elements on the stator corresponding to the second magnetic steel ring is 360° /N.

 Preferably, on the stator, corresponding to an angle between two adjacent magnetic induction elements of the first magnetic steel ring, when m is 2 or 4, the angle between each adjacent two magnetic induction elements is 90°/N When m is 3, the angle between each adjacent two magnetic induction elements is 120 N; when m is 6, the angle between each adjacent two magnetic induction elements is 60°/N.

 Preferably, the magnetic sensing element is directly attached to the inner surface of the stator.

 The control motor further includes two magnetically conductive rings, each of which is composed of a plurality of arcs of the same center and the same radius, and adjacent two arcs have a gap, corresponding to two magnetic steel rings. The magnetic sensing elements are respectively disposed in the gap.

 Preferably, the end of the arc of the magnetic flux ring is chamfered.

 Preferably, the chamfer is a chamfer formed by cutting axially or radially or simultaneously in the axial direction and in the radial direction.

 Preferably, the magnetic sensing element is a Hall sensing element.

 Preferably, the motor body and the controller are integrally provided.

 Preferably, the controller includes a housing and a control module, the housing enclosing the control module within the housing and secured to the motor by a connector.

 Preferably, the magnetoelectric sensor is disposed within the housing and between the motor and the control module or behind the control module. The control motor further includes a fan for dissipating heat from the motor and the controller.

 Preferably, the fan is located within the housing and is placed between the outermost end of the housing remote from the motor or between any two of the motor, control module and magnetoelectric sensor.

 Preferably, the control module comprises a data processing unit, a motor driving unit and a current sensor, and the data processing unit receives the input command signal, the motor input current signal collected by the current sensor, and the information representing the motor angle output by the magnetoelectric sensor. After data processing, the control signal is output to the motor driving unit, and the motor driving unit outputs an appropriate voltage to the motor according to the control signal, thereby achieving precise control of the motor.

Preferably, the data processing unit comprises a mechanical loop control subunit, a current loop control subunit, a PWM control signal generating subunit, and a sensor signal processing subunit. The sensor signal processing subunit receives the generation of the magnetoelectric sensor output The information of the angle of the motor is obtained by A/D sampling and angle solving, and the rotation angle of the motor shaft is obtained, and the angle is transmitted to the mechanical ring control subunit; the sensor signal processing subunit further receives the current sensor The detected current signal is sampled by A/D and output to the current loop control subunit. The mechanical ring control subunit obtains a current command through operation according to the received command signal and the rotation angle of the motor shaft, and outputs the current command to the current loop control subunit. The current loop control subunit obtains a duty control signal of the three-phase voltage through operation according to the current signal output by the current sensor of the received current command, and outputs the duty control signal to the PWM control signal generating subunit. The PWM control signal generating sub-unit generates six PWM signals having a certain order according to the received duty control signal of the three-phase voltage, and respectively acts on the motor driving unit.

 Preferably, the motor driving unit comprises six power switching tubes, the switching tubes are connected in series in two groups, three groups are connected in parallel between the DC power supply lines, and the control end of each switching tube is generated by a PWM control signal. The control of the PWM signal output by the unit, the two switching tubes in each group are time-divisionally turned on.

 Preferably, the sensor signal processing subunit includes a signal processing circuit of the magnetoelectric sensor, and is configured to obtain a rotation angle of the motor shaft according to the voltage signal of the magnetoelectric sensor, and specifically includes: an A/D conversion circuit, and a relative bias Shift angle calculation circuit, absolute offset calculation circuit, angle synthesis and output module and storage module. The A/D conversion circuit performs A/D conversion on the voltage signal sent by the magnetoelectric sensor to convert the analog signal into a digital signal; and the relative offset angle calculation circuit is used to calculate the corresponding value in the magnetoelectric sensor. a relative offset of the first voltage signal transmitted by the magnetic induction element of the first magnetic steel ring in a signal period; the absolute offset calculation circuit is configured according to the second magnetic steel ring of the magnetoelectric sensor a second voltage signal sent by the magnetic sensing element, the absolute offset of the first position of the signal period at which the first voltage signal is located is determined by calculation; the angle synthesis and output module is configured to use the relative offset and the absolute offset The shift amount is added to synthesize a rotation angle represented by the first voltage signal at the moment; the storage module is configured to store data.

 In addition, the signal processing circuit of the magnetoelectric sensor further includes a signal amplifying circuit for amplifying the voltage signal from the magnetoelectric sensor before the A/D conversion module performs A/D conversion.

 Preferably, the relative offset angle calculation circuit includes a first synthesis circuit and a first angle acquisition circuit, and the synthesis circuit processes the A/D-converted voltage signals sent by the magnetoelectric sensor to obtain a The reference signal D; the first angle acquisition circuit selects an angle opposite thereto as the offset angle in the first angle storage table according to the reference signal D.

 Preferably, the relative offset angle calculation circuit further includes a temperature compensation circuit for eliminating the influence of temperature on the voltage signal transmitted by the magnetoelectric sensor.

 Preferably, the relative offset angle calculating circuit further comprises a coefficient correcting circuit that performs an operation according to an output of the synthesizing circuit to obtain an output signal 1^.

 Preferably, the temperature compensation circuit includes a plurality of multipliers, each of the multipliers multiplying a voltage signal sent by the A/D converted magnetoelectric sensor by the output signal K, and multiplying the multiplied signal The result is output to the first synthesis circuit.

 Preferably, the absolute offset calculation circuit includes a second synthesis circuit and a second angle acquisition circuit, and the decoder is configured to perform a second voltage signal sent by the magnetoelectric sensor corresponding to the second magnetic steel ring. Processing, a signal E is obtained; the second angle acquiring circuit selects an angle opposite to the signal in the second standard angle table as the absolute offset of the first position of the signal period in which the first voltage signal is located.

 Preferably, the data processing unit is an MCU, and the motor driving unit is an IPM module.

 In addition, the motor body includes three-phase windings, and each of the phase windings is composed of a plurality of winding heads and tails connected in series, and a control switch is connected between each of the winding heads and the input power source.

The control switch is an electronic power switch. Further, the electronic power switch is a thyristor or an IGBT. The data processing unit further includes a torque switching subunit, the torque switching subunit selects a corresponding winding according to the torque required to be output by the motor, and outputs a control command to the control switch of the motor to respectively control each item. A combination of on and off of a plurality of control switches in the winding.

 In the electric motor according to the present invention, the number of magnetic poles of the magnetic steel involved in the magnetoelectric sensor is independent of the number of magnetic poles of the rotor of the motor, so that the matching of the motor and the magnetoelectric sensor is flexible, and the motor of the present invention Since the sensor of such a structure is used, the control accuracy, the system response speed, and the reliability are greatly improved, and the production cost is lowered, thereby improving the cost performance of the motor described in the present invention.

 Since the inner winding of the motor of the present invention can be formed by connecting a plurality of stages in series, the motor can be controlled by controlling the winding inside the motor; since the winding in the present invention is variable, the low winding can be selected under low load conditions. State, thus reducing the operating current of the motor, thereby achieving the purpose of energy saving; the common motor winding is fixed, and the motor cannot be operated normally when any phase winding is damaged, and the phase winding of the present invention is composed of a plurality of windings, so even One winding is damaged, but the other windings can also work, so the reliability is improved, the fabrication is simple, and the cost is low. DRAWINGS

 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an exploded view of a control motor to which a fan is attached according to the present invention.

 Fig. 2 is an exploded view of the control motor in which the fan is not mounted in the present invention.

 3A, 3B and 3C are respectively an exploded perspective view, a schematic view and a structural view of an electromagnetic sensor structure provided with a magnetically permeable ring of the present invention.

 4A-4D are chamfering designs of the magnetically permeable ring of the present invention.

 FIG. 5 is a flow chart of a signal processing method of the electromagnetic sensor according to the present invention.

 6 is a second flowchart of a signal processing method of the electromagnetic sensor according to the present invention.

 7 is a third flowchart of a signal processing method of the electromagnetic sensor according to the present invention.

 FIG. 8 is a fourth flowchart of a signal processing method of the electromagnetic sensor according to the present invention.

 Figure 9 is a structural view showing a first magnetic steel ring, a magnetic flux ring, and a magnetic induction element of Embodiment 1 of the present invention.

 Fig. 10 is a view showing the positional relationship between the magnetization magnetic sequence of the first magnetic steel ring and the magnetic induction element according to the first embodiment of the present invention.

 Figure 11 is a flow chart of the algorithm for the magnetization magnetic sequence of the second magnetic steel ring.

 Figs. 12A to 12B are views showing the positional relationship between the magnetization magnetic sequence of the second magnetic steel ring and the magnetic induction element according to the first embodiment of the present invention. Figure 13 is a block diagram of a signal processing device according to Embodiment 1 of the present invention.

 Fig. 14 is a view showing the configuration of a first magnetic steel ring Hall element, a magnetic conducting ring, and a magnetic sensing element in the electromagnetic sensor of the second embodiment of the present invention.

 Figure 15 is a view showing the positional relationship between the magnetization magnetic sequence of the first magnetic steel ring and the magnetic induction element according to the second embodiment of the present invention.

 Figure 16 is a block diagram of a signal processing device according to a second embodiment of the present invention.

 Figure 17 is a schematic view showing the structure of a first magnetic steel ring Hall element, a magnetic conductive ring, and a magnetic induction element according to Embodiment 3 of the present invention. Figure 18 is a view showing the positional relationship between the magnetization magnetic sequence of the first magnetic steel ring and the magnetic induction element in the third embodiment of the present invention.

 Figure 19 is a block diagram of a signal processing device according to a third embodiment of the present invention.

 Figure 20 is a schematic view showing the structure of a first magnetic steel ring Hall element, a magnetic conductive ring, and a magnetic induction element according to Embodiment 4 of the present invention. Figure 21 is a view showing the positional relationship between the magnetization magnetic sequence of the first magnetic steel ring and the magnetic induction element in the fourth embodiment of the present invention.

 Figure 22 is a block diagram of a signal processing device according to a fourth embodiment of the present invention.

23A-23B are distribution diagrams of a magnetic induction element, a magnetically permeable ring, and a stator corresponding to a second magnetic steel ring according to the present invention. Figure 24 is an exploded perspective view showing the structure of an electromagnetic sensor in which the magnetic induction element of the present invention is directly attached to an electromagnetic sensor. 25A-25D are schematic views showing the structure of the magnetic induction element directly on the first magnetic steel ring directly attached to the electromagnetic sensor.

 Figure 26 is a simplified diagram of the control structure of the motor system.

 Figure 27 is a schematic diagram of the control structure of the motor system.

 Figure 28 is a schematic diagram of another motor system control structure.

 Figure 29 is a block diagram of a mechanical ring.

 Figure 30 is a block diagram of the mechanical ring with only the speed loop.

 Figure 31 is a block diagram of the current loop.

 Figure 32 is a block diagram of the PWM signal generation module.

 Figure 33 is a schematic diagram of the IPM.

 Figure 34 is a wiring diagram of the winding inside the motor body.

 Figure 35 is a schematic diagram of a control structure having a plurality of windings inside the motor body. detailed description

 The invention will be described in detail below with reference to the drawings and specific embodiments.

 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an exploded view of a control motor to which a fan is attached according to the present invention. Fig. 2 is an exploded view of the control motor in which the fan is not mounted in the present invention. As shown in Figs. 1 and 2, the control motor of the present invention includes a motor body 501, a controller, and a magnetoelectric sensor. The controller includes a controller housing 507 and a control module 502. The magnetoelectric sensor is used to sense the rotation of the motor shaft, and transmits the sensed voltage signal to the controller. Through the processing of the controller, the angle or position of the motor shaft rotation is obtained, thereby achieving precise control of the motor.

 The motor body and the controller in the invention can be integrally arranged, and the integrated transmission arrangement shortens the transmission path of the magnetoelectric sensor signal and reduces signal interference, thereby improving the reliability of the control.

 The control motor of the present invention may also be equipped with a fan 508 for dissipating heat from the motor and the controller. Fan 508 is located within fan shroud 509 and is placed between the outermost end of the housing remote from the motor or between any two of the motor body 501, control module 502, and magnetoelectric sensor.

 Magnetoelectric sensor

 The magnetoelectric sensor used in the present invention may or may not include a signal processing circuit, and if it does not include a signal processing circuit, the circuit is located in the controller. The signal processing circuit described in the following description of the magnetoelectric sensor is the same as the processing when the circuit is located in the control, and therefore, the description of the processing module of the controller will not be repeated.

 3A, 3B and 3C are respectively an exploded perspective view, a schematic view and a structural view of an electromagnetic sensor structure provided with a magnetically permeable ring of the present invention. As shown in Figs. 3A, 3B and 3C, the electromagnetic sensor of the present invention is composed of a magnetic steel ring 302, a magnetic steel ring 303, a magnetic conducting ring 304, a magnetic conducting ring 305, a bracket 306, and a plurality of magnetic sensing elements. Specifically, the diameters of the magnetic steel rings 302 and 303 are smaller than the diameters of the magnetic conductive rings 304 and 305, so that the magnetic conductive rings 304 and 305 are respectively sleeved outside the magnetic steel rings 302 and 303, and the magnetic steel rings 302 and 303 are fixed to the rotating shaft 301. Upper, and the magnetic flux rings 304, 305 and the magnetic steel rings 302, 303 are relatively rotatable such that the plurality of sensor elements 307 disposed on the inner surface of the bracket 306 are within the gaps of the magnetic steel ring.

FIG. 3C is a plan view showing the components of the electromagnetic sensor provided with the magnetically permeable ring of the present invention. FIG. 3C shows that the magnetic steel ring 302 and the magnetic steel ring 303 are arranged in parallel on the shaft 301, corresponding to Two rows of magnetic sensing elements 308 and 309 are respectively disposed on the magnetic steel ring 302 and the magnetic steel ring 303. Here, for the convenience of the following description, the first column of magnetic induction elements, that is, the corresponding magnetic steel ring 302 The plurality of magnetic sensing elements of the magnetically conductive ring 304 are represented by a magnetic sensing element 308, and the magnetic sensing elements 309 of the second magnetic sensing element, i.e., the corresponding magnetic steel ring 303 and the magnetically conductive ring 305, are represented by a magnetic sensing element 309. For convenience of explanation, the magnetic steel ring 302 is defined as a first magnetic steel ring, the magnetic steel ring 303 is defined as a second magnetic steel ring, and the magnetic conductive ring 304 is defined to correspond to the first magnetic steel ring, and the magnetic conductive ring is to be 305 is defined to correspond to the second magnetic steel ring 303, and then the invention is not limited to the above definition.

 As shown in FIG. 4A-4D, the magnetic flux ring is composed of two or more segments of the same radius and the same center, and the end of the arc is chamfered, and the chamfer is along the axial or radial or simultaneous edges. Chamfer formed by axial and radial cutting. The chamfer is a chamfer formed by cutting in the axial direction 351 or the radial direction 352 or simultaneously in the axial direction 354 and the radial direction 353.

 According to the magnetic density formula β = · ^, we can know that when ^ is certain, it can be reduced by β.

 Since the pass generated by the permanent magnet is constant and large in the magnetic conductive ring, the enthalpy is relatively small, so that the heat generation due to the alternating magnetic field can be reduced. By reducing the end area of the magnetic flux ring, the magnetic field strength of the end portion can be increased, so that the output signal of the magnetic induction element is enhanced. Such a signal pickup structure has a simple manufacturing process, low signal noise picked up, low production cost, high reliability, and small size.

 a gap is left between two adjacent arc segments, and a magnetic induction element is placed in the gap. When the magnetic steel ring and the magnetic flux ring rotate relative to each other, the magnetic induction element converts the sensed magnetic signal into a voltage signal, and This voltage signal is transmitted to the corresponding controller. Such a signal pickup structure has a simple manufacturing process, low signal noise picked up, low production cost, high reliability, and small size.

The first magnetic steel ring 302 is uniformly magnetized to Ν(Ν<=2 ^η (η=0, 1, 2...! ι)) to the magnetic pole, and the polarities of the adjacent two poles are opposite, and the magnetic pole of the second magnetic steel ring The total number is N, and the magnetic order is determined by a magnetic order algorithm; on the bracket 306, corresponding to the first magnetic steel ring 302, m (m is 2 or 2) on the same circumference centered on the center of the first magnetic steel ring 302. An integer multiple of 3) a magnetic induction element 308 distributed at an angle; corresponding to the second magnetic steel ring 303, n (n = 0, 1, 2) is provided on the same circumference centered on the center of the second magnetic steel ring 303 ...! 1) A magnetic sensing element 309 distributed at an angle of 360° / N.

 The magnetic field sensor may further include a signal processing device, including an A/D conversion module, a relative offset angle calculation module, an absolute offset calculation module, an angle synthesis and output module, and a storage module, where the A The /D conversion module performs A/D conversion on the voltage signal sent from the electromagnetic sensor, and converts the analog signal into a digital signal; the relative offset angle calculation module is used to calculate the first magnetic steel ring in the electromagnetic sensor a relative offset of the first voltage signal sent by the magnetic sensing element during the signal period; the absolute offset calculating module sends a second according to the magnetic sensing element corresponding to the second magnetic steel ring of the electromagnetic sensor a voltage signal, the absolute offset of the first position of the signal period at which the first voltage signal is located is determined by calculation; the angle synthesis and output module is configured to add the relative offset and the absolute offset, and synthesize the a rotation angle represented by the first voltage signal at the moment; the storage module is configured to store an angle obtained during the calibration process and Coefficient K correction data.

The flow corresponding to the above processing device is as shown in FIG. 5-8. As shown in FIG. 5, the voltage signal sent from the first magnetic steel ring and the second magnetic steel ring in the electromagnetic sensor is A/D converted, and the analog signal is obtained. Converting to a digital signal; performing an angle solution on the first voltage signal corresponding to the first magnetic steel ring sent by the electromagnetic sensor by the relative offset calculation module, and calculating a signal period corresponding to the signal of the first magnetic steel ring The relative offset of the signal; the absolute offset calculation module performs an angle solution on the first voltage signal corresponding to the second magnetic steel ring sent by the electromagnetic sensor to determine the first position of the signal period where the first voltage signal is located Absolute offset; through the angle synthesis and output module, such as an adder for adding the relative offset and the absolute offset, synthesizing the rotation angle represented by the first voltage signal at the moment. For FIG. 6, a signal amplifying module added on the basis of FIG. 5, specifically as an amplifier, is used to amplify a voltage signal from the electromagnetic sensor before the A/D conversion module performs A/D conversion. Figure 7 is a flow chart of signal processing including temperature compensation. Before the angle is solved, the process of temperature compensation is also included. Figure 8 is a specific process based on the temperature compensation of Figure 7, that is, when performing temperature compensation, The coefficient is corrected, and then the temperature of the signal output from the A/D converter and the coefficient corrected output are multiplied by a multiplier to perform temperature compensation. Of course, there are many specific ways of temperature compensation, which are not introduced here.

 Hereinafter, an electromagnetic sensor of the present invention and a signal processing apparatus and method thereof will be described in detail by way of embodiments.

 Example 1

 Embodiment 1 of the present invention provides an electromagnetic sensor in which a first column of magnetic sensing elements is provided with two magnetic sensing elements 308 and a second column of sensing elements is provided with three magnetic sensing elements 309.

9 is a structural view of a first magnetic steel ring, a magnetic flux ring, and a magnetic induction element according to Embodiment 1 of the present invention; FIG. 10 is a magnetic magnetic sequence of a first magnetic steel ring and a magnetic induction element according to Embodiment 1 of the present invention; Location diagram. The first column of magnetic sensing elements 308 corresponding to the first magnetic steel ring 302 is two, that is, m=2, and is represented by H ₂ , and the two magnetic sensing elements and H ₂ are respectively placed on the two nips of the corresponding magnetic conductive ring 304. in. The second column of magnetic sensing elements 309 corresponding to the second magnet ring 303 is three, i.e., n = 3, represented by H ₃ , 11 ₄ and . The number of magnetic poles is taken as N=8, so that the angle between the adjacent two magnetic induction elements 309 corresponding to the second magnetic steel ring 303 is 360° /8. The angle between adjacent two magnetic sensing elements 308 corresponding to the first magnetic steel ring 302 is 90°/8.

The magnetization sequence of the first magnetic steel ring 302 and the magnetic pole arrangement of H ₂ can be seen from FIG. Figure 11 is an algorithmic flow diagram of the second magnetic steel ring 303. As shown in Figure 11, first initialize a[0] = "0... 0"; then encode the current into the code set, that is, the code set has "0... 0"; then check if the set element of the code set reaches 2 ⁿ , if yes, the program ends, otherwise the current code is shifted to the left by one bit, followed by 0; then it is checked whether the current code has entered the code set, if the code set is not entered, the current code is entered into the code set to continue the above steps, if If the code set has been entered, the current code end bit is decremented by 0; then it is checked whether the current code has entered the code set. If the code set is not entered, the current code is added to the code set to continue the above steps. If the code set has been entered, the current test is checked. Whether the code is "0... 0", yes, then it ends, otherwise the current coded direct forward code end bit is 0 to 1; then it is checked whether the current code has entered the code set, if the code set is not entered, the current code is entered. The code set continues with the above steps. If the code set has been entered, it is checked whether the current code is "0...0", and then the following procedure is continued. Among them, 0 magnetization is "N/S", and 1 magnetization is "S/N". Thus, the magnetization structure diagram of the magnetic steel ring 303 shown in Fig. 12 and the arrangement order of _3⁄4 , H ₄ and H ₅ are obtained.

 Figure 13 is a block diagram of a signal processing apparatus according to Embodiment 1 of the present invention, in which an output signal of a magnetic induction element of a first magnetic steel ring is connected to an amplifier 2_la, 2_2a, an output signal of an amplifier 2_la, 2_2a is input to an A/D converter 3_la, 3_2a The input port is subjected to analog-to-digital conversion to obtain an output signal multiplier 4_la, 5_la, the output signal of the coefficient aligner 10_la is connected to the input terminals of the multipliers 4_la, 5_la, and the output signals A, B of the multipliers 4_la, 5_la are connected to the first synthesis. The input signal of the first synthesizer 6_la is the input signal of the memory 8_la and the memory 9_la, and the output signal of the memory 9_la is connected to the coefficient corrector 10_la, and the output signal of the memory 8_la is used as the input terminal of the adder 12_la.

 The output signals of the sensors l_3a, l_4a, ... l_na are respectively amplified by three amplifiers 2_3a, 2_4a, ... 2_na, and then connected to the AD converters 3_3a, 3_4a, ... 3_na for analog-to-digital conversion and then passed through the second device. 7_la is decoded, and then obtained by the memory l l_la. And the measured absolute angular displacement output is obtained by the adder 12_la.

 Wherein, during the processing of the signal, the output of the first synthesizer 6_la is performed as follows:

 Convention:

 When the data X is a signed number, the 0th bit of the data X (the 1st bit from the left of the binary) is the sign bit, X_0=1 means the data X is negative, and X_0=0 means the data X is positive.

 _0 indicates the value bit of the data X (the absolute value of the data), that is, the remaining data bits are removed from the sign bit.

 Comparing the magnitudes of the two signals, the value of the signal D for the output is small, the structure of the signal D is {the coincidence of the first signal, the coincidence of the second signal, the numerical value of the signal of the smaller value} . details as follows:

If A_D>=B_D D={ A_0; B_0; B_D }

 Otherwise:

 D={ A_0; B_0; A_D } The output of the second synthesizer 7_la is performed as follows:

 E={ C3_0; C4_0; ... Cn_0 }

 The signal K is generally passed by the signal R. And R is divided.

 For the first and second standard angle tables, two tables are stored in the memory, each table corresponding to a series of codes, each code corresponding to an angle. The table is obtained by calibration, and the calibration method is: using the detecting device of the embodiment and a high-precision position sensor, the signals output by the magnetic sensing element in the embodiment and the angle of the high-precision position sensor output are in one-to-one correspondence. In order to establish a relationship between the signal and the angle of the output of a magnetic induction element. That is, a first standard angle table is stored corresponding to the signal D, and each signal D represents a relative offset. Corresponding to the signal Ε, a second standard angle table is stored, and each signal Ε represents an absolute offset.

 Example 2

 A second embodiment of the present invention provides a schematic view in which four magnetic induction elements are provided corresponding to the first magnetic steel ring 302.

 14 is a schematic structural view of a first magnetic steel ring Hall element, a magnetic conductive ring, and a magnetic induction element in the electromagnetic sensor according to Embodiment 2 of the present invention; and FIG. 15 is a magnetic magnetic field of the first magnetic steel ring according to Embodiment 2 of the present invention; Sequence and positional relationship with the magnetic sensing element.

As shown in FIG. 14, the first column of magnetic sensing elements 308 corresponding to the first magnetic steel ring 302 is four, that is, m=4, represented by H ₂ , 3⁄4 and 3⁄4, the two magnetic sensing elements, 3⁄4, 3⁄4 and respectively Placed in the four nips corresponding to the first magnetically conductive ring 304. The second column of magnetic sensing elements 309 corresponding to the second magnet ring 303 is three, i.e., n = 3, and is represented by H ₅ , H _{6 ,} and H ₇ . Taking N=8, the angle between the adjacent two magnetic sensing elements 309 corresponding to the second magnetic steel ring 303 is 360° /8. The angle between adjacent two magnetic sensing elements 308 corresponding to the first magnetic steel ring 302 is 90 8 .

From Fig. 15, the magnetization sequence of the magnetic steel ring 302 and the magnetic pole arrangement of _{3⁄4, 3⁄4} and H ₄ can be seen. The magnetization structure and algorithm flow of the second magnet ring 303 are the same as those of the first embodiment, and the description thereof will be omitted herein.

Figure 16 is a block diagram of a signal processing device according to a second embodiment of the present invention. The signal processing device and the processing method are similar to those of Embodiment 1, except that since there are four magnetic sensing elements in the second embodiment, the output signals of the magnetic sensing elements l_lc (H and l_2c (H ₂ ) of the first magnetic steel ring are amplified. The circuit 2-lc performs differential amplification, and the output signals of the magnetic induction elements l_3c (H ₃ ) and l_4c (H ₄ ) of the first magnetic steel ring are differentially amplified by the amplifying circuit 2-2c, and finally the signal output to the synthesizer is still The processing procedure and the method are the same as those in Embodiment 1. Therefore, details are not described herein again.

 Example 3

 A third embodiment of the present invention provides a structural view in which three magnetic induction elements are provided corresponding to the first magnetic steel ring.

 17 is a schematic structural view of a first magnetic steel ring Hall element, a magnetic conductive ring, and a magnetic induction element according to Embodiment 3 of the present invention; FIG. 18 is a first magnetic steel ring magnetic charging magnetic sequence and magnetic induction element according to Embodiment 3 of the present invention; Location map;

As shown in FIG. 17, the first column of magnetic sensing elements 308 corresponding to the first magnetic steel ring 302 is three, that is, m=3, used! ^, 3⁄4 and 3⁄4 indicate that the two magnetic sensing elements Η ₂ and 3⁄4 are respectively placed in the three nips corresponding to the first magnetically conductive ring 304. The second column of magnetic sensing elements 309 corresponding to the second magnet ring 303 is three, i.e., η = 3, and is represented by Η ₄ , Η _{5 ,} and _3⁄4 . Taking Ν = 8, such that the angle between the adjacent two magnetic sensing elements 309 corresponding to the second magnet ring 303 is 360° / 8. The angle between the adjacent two magnetic sensing elements 308 corresponding to the first magnetic steel ring 302 is 120°/8. The magnetization sequence of the magnetic steel ring 302 and the magnetic pole arrangement of 3⁄4 and 3⁄4 can be seen from Fig. 18. The magnetization structure and algorithm flow of the second magnet ring 303 are the same as those of the first embodiment, and the description thereof will be omitted herein.

 Figure 19 is a block diagram of a signal processing device according to a third embodiment of the present invention. Different from the first embodiment, there are three magnetic induction elements and three signals output to the synthesizer. The synthesizer is different from the first embodiment in processing signals, and the rest is the same as the first embodiment. Here, only the synthesizer is processed to get 0 and .

 In this embodiment, the processing of the signal, that is, the output principle of the first synthesizer 7_lb is: first, the coincidence bits of the three signals are judged, and the magnitudes of the values of the signals conforming to the same bit are compared, and the value is small for output. Signal D, the structure of signal D is {the coincidence of the first signal, the coincidence of the second signal, the coincidence of the third signal, the value of the signal of the smaller value}. Take this example as an example:

 Convention:

 When the data X is a signed number, the 0th bit of the data X (the 1st bit from the left of the binary) is the sign bit, X_0=1 means the data X is negative, and X_0=0 means the data X is positive.

 _0 indicates the value bit of the data X (the absolute value of the data), that is, the remaining data bits are removed from the sign bit.

 If { A_0; B-0; C_0}=010 and A_D>= C_D

 D={ A—0; B_0; C_0; C— D }

 If { A_0; B_0; C_0}=010 and A_D< C_D

 D={ A_0; B_0; C_0; A—D};

 If { A_0; B_0; C_0}= :101 and A_D>= C_D

 D={ A_0; B_0; C_0; C- D };

 If { A_0; B_0; C_0}: = 101 and A_D< C_D

 D={ A_0; B_0; C_0; A—D};

 If { A_0; B_0; C_0}=011 and B_D>=C_D

 D={ A_0; B_0; C_0; c- D };

 If { A_0; B_0; C_0}=011 and B_D<C_D

 D={ A_0; B_0; C_0; B- D };

 If { A_0; B_0; C_0}=100 and B_D>=C_D

 D={ A_0; B_0; C_0; c- D };

 If { A_0; B_0; C_0}= :100 and B_D<C_D

 D={ A_0; B_0; C_0; B- D };

 If { A_0; B_0; C_0}=001 and B_D>=A_D

 D={ A_0; B_0; C_0; A—D};

 If { A_0; B_0; C_0}=001 and B_D<A_D

 D={ A_0; B_0; C_0; B- D };

 If { A_0; B_0; C_0}= :110 and B_D>=A_D

 D={ A_0; B_0; C_0; A—D};

 If { A_0; B_0; C_0}= :110 and B_D<A_D

D={ A_0; B_0; C_0; B- D }; a = A - B x cos (―) - Cx cos (―) β = Β s sin(—) - C x sin (―)

 Example 4

 According to a fourth embodiment of the present invention, there is provided a structural view in which six magnetic induction elements are provided corresponding to the first magnetic steel ring.

 20 is a schematic structural view of a first magnetic steel ring Hall element, a magnetic conductive ring, and a magnetic induction element according to Embodiment 4 of the present invention; and FIG. 21 is a magnetic magnetic flux and magnetic induction element of a first magnetic steel ring according to Embodiment 4 of the present invention; Location map.

As shown in FIG. 20, the first column of magnetic sensing elements 308 corresponding to the first magnetic steel ring 302 is six, that is, m=6, used! ^, H ₂ ,

H ₃ , H ₄ , H ₅ and H ₆ indicate that the two magnetic induction elements Η ₂ , Η ₃ , Η ₄ , Η ₅ and Η ₆ are respectively placed in the six nips corresponding to the first magnetically conductive ring 304. The second column of magnetic sensing elements 309 corresponding to the second magnet ring 303 is three, i.e., η = 3, represented by Η ₇ , 3⁄4 and . Taking Ν = 8, such that the angle between the adjacent two magnetic sensing elements 309 corresponding to the second magnet ring 303 is 360° / 8. The angle between adjacent two magnetic sensing elements 308 corresponding to the first magnetic steel ring 302 is 60 8 .

The magnetization sequence of the magnetic steel ring 302 and the arrangement of Η ₂ , Η ₃ , Η ₄ , Η ₅ and Η ₆ can be seen from Fig. 21 . The magnetization structure and algorithm flow of the first magnetic steel ring 302 are the same as those of the first embodiment, and the description thereof will be omitted herein.

Figure 22 is a block diagram of a signal processing device according to a fourth embodiment of the present invention. Different from the third embodiment, there are six magnetic induction elements. Therefore, the output signals of the magnetic induction elements l_3c (H ₃ ) and l_4c (H ₄ ) of the first magnetic steel ring are differentially amplified by the amplification circuit 2-ld. The output signal of the magnetic induction element l_3d(H ₃ ) l_4d(H ₄ ) of a magnetic steel ring is differentially amplified by the amplifying circuit 2-2d, and the magnetic sensing element l_5d(H ₅ ) l_6d(H ₆ ) of the first magnetic steel ring The output signal is amplified by the amplifier circuit 2-3d, and the signal output to the synthesizer is still three. The processing and method are the same as in the third embodiment.

 The above four embodiments are various embodiments in which the value of m changes in the case of n = 3, and the present invention is not limited thereto, and the magnetic sensing element n on the second magnetic steel ring may be an arbitrary integer (n = 0, 1, 2...! ι), as shown in Figs. 23A to 23B, are distribution points of the second magnetic steel ring, the magnetic flux ring, and the magnetic induction element when n = 4, 5, respectively. The respective magnetization sequences and algorithm flows are similar to those of Figs. 10 and 11, respectively, and a detailed description thereof will be omitted herein.

 Figure 24 is an exploded perspective view showing the structure of an electromagnetic sensor in which the magnetic induction element of the present invention is directly attached to an electromagnetic sensor. 25A-25D are schematic structural views of a magnetic induction element corresponding to a first magnetic steel ring directly attached to an electromagnetic sensor, respectively. In the case where the magnetic induction element is directly attached to the electromagnetic sensor, the order of arrangement of the magnetic induction elements is the same as that of the above-described magnetically conductive ring, and the signal processing apparatus and method are also the same, and detailed description thereof will be omitted.

 Controller

 The controller includes a controller housing 507 and a control module 502 that houses the control module 502 therein and is secured to the motor body 501 by a connector.

Figure 26 is a block diagram showing the structure of the motor system. The motor system consists of a servo controller, a motor and an encoder. The encoder described herein and the encoder referred to in the following figures are the magnetoelectric sensors described in the present invention. The control module includes a data processing unit, a motor drive unit, and a current sensor. The data processing unit is an MCU, and the motor driving unit is an IPM module. The MCU receives the input command signal, the motor input current signal collected by the current sensor, and the voltage signal output by the magnetoelectric sensor. After data processing, the PWM signal is output to the IPM, and the IPM outputs a three-phase voltage to the motor according to the PWM signal, thereby realizing the motor. Precise control. The whole system is a closed-loop control system with a short control period (a control period of only a few tens of microseconds), fast response and high precision. Figure 27 is a schematic diagram of the control structure of the motor system. At this time, the signal processing circuit of the magnetoelectric sensor is located in the sensor, and the controller only needs to receive the signal of the sensor through the synchronous communication interface. As shown in Fig. 27, inside the MCU, there are CPU, A/D, synchronous communication port and PWM signal generation module, etc. The A/D converts the analog signal input from the current sensor to the MCU into a digital signal, thereby obtaining current feedback. The encoder transmits the motor angular position information to the MCU via the synchronous port communication. The CPU in the MCU runs the control program based on current feedback and angle feedback. The control program mainly includes a mechanical ring and a current loop. The mechanical loop calculates a current command according to the set command and the angle feedback, and the current loop calculates a three-phase voltage duty ratio according to the current command and the current feedback. The PWM signal generation module generates a PWM signal according to the three-phase voltage duty ratio and transmits it to the IPM. The IPM generates a three-phase voltage to the motor based on the PWM signal.

 28 is a schematic diagram of another motor system control structure, in which a controller includes a signal processing circuit for processing a voltage signal from a magnetoelectric sensor, the portion being the same as described above in the description of the magnetoelectric sensor. The signal processing circuit is the same; the other portions are the same as those of FIG. 27, and therefore, the description will not be repeated here.

 Figure 29 is a block diagram of a mechanical ring. As shown in Figure 29, the mechanical loop calculates the current command and transmits it to the current loop based on the angle command and the angle feedback of the encoder. The mechanical ring consists of a position loop and speed loop, a position loop output speed command, and a speed loop output current command.

 The angle command is an instruction set by the control program or calculated according to the set command. The encoder detects the angular position signal of the motor shaft, and transmits the angle signal to the MCU through the synchronous port communication, and the MCU obtains angle feedback. The angle command is subtracted from the angle feedback to obtain the angle error. The PID controller controls the angle to obtain the speed command. The PID control of the angle is called the position loop, and the position loop outputs the speed command, which is transmitted to the speed loop. The angle feedback is obtained by the differentiator, the speed command is subtracted from the speed feedback, and the speed error is obtained. The PID controller controls the speed to obtain the current command K. The PID control of speed is called the speed loop. The current command is the output of the speed loop, also the output of the mechanical loop, and the mechanically commutated output current command ^-w/ is given to the current loop.

 Figure 30 is a block diagram of the mechanical ring with only the speed loop. In some cases, there is no need to position the motor and only speed control is required, so there is no position loop in the mechanical ring, only the speed loop. The speed command is an instruction set by the control program. The encoder detects the angular position signal of the motor shaft, and transmits the angle signal to the MCU through the synchronous port communication. The MCU obtains the angle feedback, and the angle feedback obtains the speed feedback through the differentiator. The speed command is subtracted from the speed feedback to obtain the speed error. The PID controller controls the speed to obtain the current command K. The PID control of speed is called the speed loop. The current command is the output of the speed loop, also the output of the mechanical loop, and the mechanical output current command is given to the current loop.

 Figure 31 is a block diagram of the current loop. The current loop generates a three-phase voltage duty cycle applied to the PWM signal generation module based on the current command output from the mechanical ring and the current feedback of the current sensor.

 The current sensor can be three or two. When there are three current sensors, each current sensor detects the motor U,

The magnitude of one phase current in the V and W phases. The current sensor transmits the detected three-phase current signal to the CPU, and the CPU performs A/D sampling to convert the analog signal into a digital signal to obtain the three-phase current of the motor. Under normal circumstances, the sum of the three-phase currents of the motor is zero. When there is some abnormality in the motor, such as motor leakage, the sum of the three-phase currents is not zero. When the current sensor fails or the current A/D sampling fault occurs, the sum of the three-phase current values obtained by the CPU may not be zero. It can be used as a basis for system detection, and the alarm will be issued in time when the above fault occurs.

When there are two current sensors, the magnitude of the two-phase current in the three phases of the motor U, V, W is detected. The current sensor transmits the detected two-phase current signal to the CPU, and the CPU performs A/D sampling to convert the analog signal into a digital signal to obtain the two-phase current of the motor. Since the sum of the three-phase currents of the motor is zero, the magnitude of the third phase current can be calculated according to the magnitude of the two-phase current. In this way, only two current sensors can meet the needs of the motor system and reduce the cost. The current command for the mechanical output is ^-re/ , which is the current command for the q-axis. The signal output from the current sensor is transmitted to the MCU, and is sampled by A/D to obtain current feedback. If the current sensor is three, the three-phase current feedback ^Ια - ^β , J, ^/c is obtained directly.

A module is generated for the PWM signal.

 The above formula for 3->2 transformation is

-^β。 式中 ^， 为变换后 的 d， q轴电流，在电流环框图中对应为 ， ^-^。式中 为电机的电角度，其中： ^{= ΡΧθ Ρ}为电机的极对数， 为电机的机械角度， 为控制框图中的角度反馈，通过角度求解算法得到。 3->2, converted to d, q-axis current. Where, ^ is

- ^β . In the formula, ^ is the transformed d, q-axis current, corresponding to ^-^ in the current loop block diagram. Where is the electrical angle of the motor, where: ^{= ΡΧ θ Ρ} is the pole pair of the motor, the mechanical angle of the motor, for the angular feedback in the control block diagram, obtained by the angle solving algorithm.

 The formula for the 2->3 transformation is:

υ _Α u

算出来的需加给电机的三相电压， 在电流 环框图中对应为 U。-占空比 ， 一占空比， 占空比 。 式中 为电机的电角度= Where d, q-axis voltage, in the current loop diagram

The calculated three-phase voltage to be applied to the motor is corresponding to U in the current loop block diagram. - duty cycle, a duty cycle, duty cycle. Where is the electrical angle of the motor =

 Figure 32 is a block diagram of the PWM signal generation module. The PWM signal generation module generates six PWM signals according to the three-phase voltage duty ratio calculated by the current loop, and the control period and dead time set by the control program, and transmits the six PWM signals to the IGBT, and controls the six IGBTs inside the ΙΡΜ. The control cycle and dead time are set when the control program is written, and generally do not change during the program run. The reason for setting the dead zone is that the IGBTs of the same phase of the upper and lower legs of the IPM cannot be turned on at the same time. At the same time, the IGBT will be damaged when it is turned on. Therefore, there must be a turn-off dead zone to ensure that the IGBTs of the upper and lower arms of the same phase are not turned on at the same time.

 Figure 33 is a schematic diagram of the IPM. There are six power switching tubes (IGBTs) inside the IPM. The six IGBTs can be divided into three groups, which correspond to U, V, and W three phases. Each phase has two IGBTs, which are called upper and lower arms. The voltage between the PN is the bus voltage of the controller, and the AC power input to the controller is rectified and filtered to be converted into direct current. P and N are the positive and negative poles of the direct current.

The PWM signal generation module generates six PWM signals to control the six IGBTs inside the IPM. Taking the U phase as an example, if PWM_U is a turn-on signal, the U-phase upper arm is turned on, and the U-phase output potential is P-pole potential. If PWM_U (overlined) is a turn-on signal, then U-phase The bridge arm is turned on, and the potential of the U phase output is the N pole potential. When both PWM_U and PWM_U (overlined) are off, current flows through the freewheeling diode. When the current flows to the motor, the current flows from the N pole to the motor through the freewheeling diode of the lower arm, and the potential of the U phase potential is the N pole potential; when the current flows from the motor, the current flows through the freewheeling diode of the upper arm. From the motor to the P pole, the potential of the U phase output is the P pole potential. The motor body and the fan can be any of the prior art. I will not repeat them here.

 In addition, the motor body of the present invention comprises three-phase windings, and each of the phase windings is composed of a plurality of winding heads and tails connected in series, and a control switch is connected between the head of each of the windings and the input power source. As shown in Fig. 34, it is a schematic diagram of the installation and control of an embodiment of the motor winding. In this embodiment, each phase of the motor winding is composed of two windings, for example, L11 and L12 head and tail are connected in series to form one phase, and the heads of L11 and L12 are respectively connected to control switches K3, Κ4, Κ3, and 另一4 are connected in parallel at the other end. Together, with V phase, in the same way, L21 and L22 head and tail are connected in series to form one phase, and the heads of L21 and L22 are respectively connected to control switches K1, Κ2, Kl, Κ2 and the other ends are connected in parallel, connected with U phase. , L31 and L32 head and tail are connected in series to form one phase. The heads of L31 and L32 are respectively connected to the control switches Κ5, Κ6, and the other ends of Κ5 and Κ6 are connected in parallel to be connected to W.

 The control of the motor having the multi-segment winding is as shown in Fig. 35. This figure is only one of the other parts of the motor controller, and of course includes various modifications of the other parts of the controller described above.

 ΙΡΜ After receiving the PWM-modulated signal, the U, V, W three-phase voltage is output. Since the voltage is output after PMW modulation, the amplitude of the voltage is determined.

When the load is large and the torque requirement is large, because the magnitude of the torque is proportional to ΝΙ (Ν is the number of turns of the coil, I is the current flowing through the coil), if the Ν is small, then a larger The current meets the torque requirement, but is limited by the maximum current that the motor winding coil can flow. Therefore, this method may not meet the torque requirement. Therefore, it is necessary to increase the number of turns of the coil to meet the torque requirement. The switch Κ1, Κ3, Κ5 are controlled to be in the closed state by the torque switching subunit in the controller, and the control switches Κ2, Κ4, Κ6 are placed in the off state, at this time, the motor winding coils L11, L12, L21, L22, L31, L32 are all energized, the motor is in high winding state, the back electromotive force of the motor = 4.44Wf _m (N is the number of turns of the coil, f is the rotor frequency, ^ flux) increases, and u-E m + IXi decreases Because the motor current I is positively correlated with (UE), the current in the motor is reduced, so that the current flowing through the winding coil is smaller than the maximum current of the winding of the motor winding, and at the same time, because the number of turns of the coil is significant. Plus, the torque T can be increased to achieve the required load.

In the case where the load is not large but high speed is required, since the speed is high, that is, the frequency is large, a large back electromotive force is generated to make the difference of the (UE) small, which causes the current I in the motor to be reduced. The small motor torque is reduced, which suppresses the high speed of the motor. In order to better ensure the high speed of the motor, the method of reducing the number of winding turns can be adopted. By controlling the torque switching subunit, the switches K1, K3, K5 are broken. In the open state, the switches K2, K4, K6 are in the closed state. At this time, the motor windings L11, L21, L31 are in the working state and the windings L12, L22, L32 are not connected to the motor working circuit, and the coil is visible by the formula = 4.44Wf _m. After the number is reduced by 1/2, the same back-EMF frequency f can be doubled, that is, the speed can be doubled on the original basis, so the control method for reducing the number of turns of the coil can be made smaller under the same working speed. The back electromotive force, thereby obtaining a larger current, makes the motor torque increase and the high speed performance better meets the working requirements.

 The control switch in Figure 34 can be in the form of an electronic power switch, such as a thyristor or IGBT.

 The above is only one embodiment of the motor winding. The number of windings of each phase is not limited to two, and may be plural. Since the principle is the same, the description will not be repeated here.

 The above embodiments are only intended to illustrate the technical solutions of the present invention and not to limit them. While the present invention has been described in detail with reference to the embodiments of the present invention, it will be understood by those skilled in the art that the invention may be modified and equivalently substituted without departing from the spirit and scope of the present invention. Within the scope of the claims of the present invention.

 It should be noted that the above embodiments are only intended to illustrate the invention and are not to be construed as limiting the scope of the invention. The spirit and scope of the invention are intended to be included within the scope of the appended claims.

Claims

Claim  I. An electric motor comprising a motor body, a controller and a magnetoelectric sensor, wherein the magnetoelectric sensor is configured to sense rotation of a motor shaft and transmit the sensed voltage signal to a controller, Through the processing of the controller, the angle or position of the rotation of the motor shaft is obtained, thereby achieving precise control of the motor;  Wherein the magnetoelectric sensor comprises a rotor and a stator that surrounds the rotor, the rotor comprising a first magnetic steel ring and a second magnetic steel ring; Wherein, the first magnetic steel ring and the second magnetic steel ring are respectively fixed on an output shaft of the motor, and the first magnetic steel ring is uniformly magnetized to? ^ [ N <= 2 ⁿ (n = 0, 1, 2 - n) ] to the magnetic pole, and the polarities of the adjacent two poles are opposite; the total number of magnetic poles of the second magnetic steel ring is N, and the magnetic order is according to a specific magnetic Sequence algorithm determination;  On the stator, corresponding to the first magnetic steel ring, m (m is an integer multiple of 2 or 3) on the same circumference centered on the center of the first magnetic steel ring; a magnetic induction element distributed at a certain angle; In the second magnetic steel ring, n (n = 0, 1, 2 - n) magnetic induction elements distributed at an angle are disposed on the same circumference centered on the center of the second magnetic steel ring;  The magnetic sensing element converts the sensed magnetic signal into a voltage signal when the rotor is relatively rotationally moved relative to the stator, and outputs the voltage signal to the controller.  2. The electric motor according to claim 1, wherein in the magnetoelectric sensor, an angle between adjacent two magnetic induction elements on the stator corresponding to the first magnetic steel ring, when m is 2 Or 4, the angle between each adjacent two magnetic sensing elements is 907N, when m is 3, the angle between each adjacent two magnetic sensing elements is 1207N; when m is 6, the angle between each adjacent two magnetic sensing elements is 607N.  3. The electric motor according to claim 1, wherein in the magnetoelectric sensor, the magnetic induction element is directly attached to an inner surface of the stator.  4. The electric motor according to claim 1, wherein the magnetoelectric sensor further comprises two magnetically conductive rings, each of the magnetic conductive rings being composed of a plurality of arcs of the same center and the same radius. A gap is left in the adjacent two arc segments, and magnetic induction elements corresponding to the two magnetic steel rings are respectively disposed in the gap.  The electric motor according to claim 4, wherein the end portion of the arc of the magnetic flux ring is chamfered.  The electric motor according to claim 5, wherein the chamfer is a chamfer formed by cutting in the axial direction or the radial direction or both in the axial direction and the radial direction.  The electric motor according to claim 1, wherein the magnetic induction element in the magnetoelectric sensor is a Hall sensing element.  8. The motor according to claim 1, wherein the motor body and the controller are integrally provided.  9. The electric motor according to claim 1, wherein the controller comprises a housing and a control module, the housing enclosing the control module in the housing and being fixed to the motor by the connecting member.  10. The electric motor according to claim 9, wherein the magnetoelectric sensor is disposed in the housing and located between the motor and the control module or behind the control module.  The electric motor according to claim 1 or 8 or 9, further comprising a fan for dissipating heat from the motor and the controller.  12. The electric motor according to claim 11, wherein the fan is located in the outer casing and is placed at an outermost end of the outer casing away from the motor or at any two of the motor, the control module and the magnetoelectric sensor. between. The electric motor according to claim 9, wherein the control module comprises a data processing unit, a motor driving unit and a current sensor, wherein the data processing unit receives the input command signal and the motor input current signal collected by the current sensor. And the information representing the angle of the motor outputted by the magnetoelectric sensor, after data processing, outputting a control signal to the motor driving unit, the motor driving unit outputting a suitable voltage to the motor according to the control signal, thereby realizing Precise control of the motor.  The electric motor according to claim 13, wherein the data processing unit comprises a mechanical loop control subunit, a current loop control subunit, a PWM control signal generating subunit, and a sensor signal processing subunit;  The sensor signal processing subunit receives information representing a motor angle output by the magnetoelectric sensor, and transmits an angle of the motor to the mechanical ring control subunit; the sensor signal processing subunit further receives the current sensor The detected current signal is sampled by A/D and output to the current loop control subunit;  The mechanical ring control subunit obtains a current command through operation according to the received command signal and the rotation angle of the motor shaft, and outputs the current command to the current loop control subunit;  The current loop control subunit obtains a duty control signal of the three-phase voltage according to the current signal output by the current sensor of the received current command, and outputs the duty control signal to the PWM control signal generating subunit;  The PWM control signal generating sub-unit generates six PWM signals having a certain order according to the received duty control signal of the three-phase voltage, and respectively acts on the motor driving unit.  15. The electric motor according to claim 13, wherein the motor drive unit comprises six power switch tubes, the switch tubes are connected in series in two groups, and three groups are connected in parallel between the DC power supply lines, each The control end of a switch tube is controlled by a PWM signal generated by a PWM control signal generating sub-unit, and the two switch tubes in each group are time-divisionally turned on.  The electric motor according to claim 14, wherein the sensor signal processing subunit or the magnetoelectric sensor includes a signal processing circuit of a magnetoelectric sensor for using a voltage signal of the magnetoelectric sensor Obtaining the rotation angle of the motor shaft, specifically including:  The A/D conversion circuit performs A/D conversion on the voltage signal sent from the magnetoelectric sensor to convert the analog signal into a digital signal.  a relative offset angle calculating circuit, configured to calculate a relative offset of the first voltage signal sent by the magnetic induction element corresponding to the first magnetic steel ring in the magnetoelectric sensor during the signal period;  An absolute offset calculation circuit determines, by calculation, an absolute offset of a first position of a signal period at which the first voltage signal is located, according to a second voltage signal sent from a magnetic induction element of the magnetoelectric sensor corresponding to the second magnetic steel ring the amount;  An angle synthesis and output module, configured to add the relative offset and the absolute offset to synthesize a rotation angle represented by the first voltage signal at the moment;  A storage module for storing data.  17. The electric motor according to claim 16, further comprising:  A signal amplifying circuit for amplifying a voltage signal from the magnetoelectric sensor before the A/D conversion module performs A/D conversion.  18. An electric motor according to claim 16 or 17, wherein  The relative offset angle calculation circuit includes a first synthesis circuit and a first angle acquisition circuit, and the first synthesis circuit processes the A/D-converted voltage signals sent by the magnetoelectric sensor to obtain a reference. The signal D is selected according to the reference signal D, and an angle opposite thereto is selected as an offset angle in the first standard standard angle table.  19. The motor of claim 18, wherein the relative offset angle calculation circuit further comprises a temperature compensation circuit for canceling the effect of temperature on the voltage signal transmitted by the magnetoelectric sensor. The electric motor according to claim 19, wherein the output of the first synthesizing circuit further comprises a signal R; The temperature compensation unit includes a coefficient corrector and a multiplier, the signal R of the output of the synthesis module to the coefficient R and a signal R in a standard state corresponding to the signal. Comparing to obtain an output signal K; the multiplier is a plurality, each of the multipliers will send an A/D converted voltage signal sent from the magnetoelectric sensor and an output signal K of the coefficient correction module Multiply, and the multiplied result is output to the first synthesis circuit.  The electric motor according to claim 16 or 17, wherein the absolute offset calculation circuit includes a second synthesis circuit and a second angle acquisition circuit, and the second synthesis circuit is configured to correspond to the second The second voltage signal sent by the magnetoelectric sensor of the magnetic steel ring is combined to obtain a signal E. The second angle acquiring circuit selects an angle relative to the second standard angle table according to the signal E as the first The absolute offset of the first position of the signal period at which the voltage signal is placed.  22. The electric motor according to claim 13, wherein the data processing unit is an MCU, and the motor driving unit is an IPM module.  The electric motor according to claim 1 or 13, wherein the motor body comprises a three-phase winding, and each of the phase windings is composed of a plurality of winding heads and tails connected in series, each of the winding heads and the input power source A control switch is connected between them.  24. The electric motor of claim 23, wherein the control switch is an electronic power switch.  The electric motor according to claim 24, wherein the electronic power switch is a thyristor or an IGBT. The electric motor according to claim 23, wherein the data processing unit comprises a torque switching subunit, wherein the moment switching subunit selects a corresponding winding according to a torque demanded by the motor, and outputs a control command. A control switch for the motor controls the combination of the opening and closing of the plurality of control switches in each of the windings.