JP2002051584A - Automatic phase regulator of pm motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To resolve the problem of a conventional automatic phase regulator such as that the wave observation by oscilloscope is required when the user conforms the phase signal of a position sensor to the induced voltage of a PM motor. SOLUTION: The zero cross point of the induced voltage waveform at the time of having rotated a PM motor 1 with no load is detected as an edge timing signal A by means of an induced voltage detector 3, a comparator 4, and an edge detecting circuit 5. A positional signal edge detecting circuit 6 detects the fall of the phase waveform from a position sensor 2 as an edge timing signal B. An offset regulating circuit 7 regulates the phase of the timing signal B with an offset control signal. An offset regulation controller 8 detects the slippage of timing between the timing signal A and the timing signal B, and controls the offset signal in the direction where this slippage time becomes zero. A motor controller 9 controls a motor, with this quantity of offset as the slippage of the position sensor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control for detecting a relationship (phase) between a magnet position and a winding position of a PM motor by a position sensor such as an encoder or a resolver, and controlling the PM motor based on the detected phase. The present invention relates to a device, and particularly to a device for automatically detecting and adjusting a phase.

[0002]

2. Description of the Related Art A PM motor used as a drive source of an electric vehicle, a hybrid electric vehicle, or the like is provided with a position sensor such as an encoder as a rotational position detecting means. The position is controlled.

In a PM motor, a magnet is attached to a rotor, and as shown in FIG. 6, a magnetic flux changes depending on a rotational position of the rotor, and an induced voltage of a stator winding changes in response to the change in the magnetic flux. When controlling the motor current of a PM motor having such a phase relationship with a microcomputer or the like, it is necessary to grasp the positional relationship of the magnets in advance, and the rotational position where the magnetic flux density peaks, that is, the zero crossing of the fall of the induced voltage, It is necessary to make the reference point coincide with the zero point of the phase signal.

[0004] The positional relationship between the magnets of the PM motor can be obtained from a position sensor attached to the PM motor. When the position sensor is attached to the shaft of the PM motor, the PM motor is rotated without load from the outside, and the position of the UVW phase is detected. The oscilloscope measures the induced voltage waveform and the output waveform of the position sensor, and adjusts the position of the position sensor so that the positional relationship is arbitrary.

[0005]

In the conventional phase adjustment, the position of the position sensor is adjusted while observing the waveform with an oscilloscope, and it takes time and effort to adjust the position of the position sensor. In addition, it is necessary to prepare an oscilloscope for adjustment. Furthermore, since a person checks the waveform, the adjustment varies, and the adjustment accuracy deteriorates.

SUMMARY OF THE INVENTION An object of the present invention is to provide a PM motor control device capable of performing accurate phase adjustment without the need for adjustment using an oscilloscope.

[0007]

According to the present invention, a difference between an induced voltage of a PM motor and a phase signal of a position sensor is detected from these waveform signals, and a value for making the difference zero is obtained as an offset amount and stored. The phase is adjusted by setting the offset amount as a correction amount in motor control, and has the following configuration.

In a control device for controlling the PM motor based on a phase signal from a position sensor provided in the PM motor,
Means for detecting, as an edge timing signal A, a zero-cross point of an induced voltage waveform when the PM motor is rotated with no load; and edge timing for detecting a falling edge of a phase waveform from a position sensor when the PM motor is rotated. Means for detecting a signal B, an offset adjustment control means for detecting a timing shift between the edge timing signal A and the edge timing signal B passed through the offset adjusting means, and the phase signal using the timing shift as an offset amount. And a motor control means for controlling the PM motor by correcting the above.

Further, the offset adjustment control means detects the edge timing signals A and B at a fixed period, and controls the offset adjustment amount of the signal B until both signals A are detected within the same period to control the offset amount. Is obtained.

The offset adjustment control means measures the time from the detection of the edge timing signal A to the detection of the edge timing signal B, and obtains the offset amount from this time and the number of rotations of the motor. I do.

[0011]

FIG. 1 is a phase adjustment circuit diagram showing an embodiment of the present invention. A position sensor 2 is mechanically coupled to a rotor shaft of the PM motor 1 at an appropriate rotation angle position.

The induced voltage detector 3 detects the induced voltage as a waveform among the UVW-phase induced voltages when the PM motor 1 is rotated at no load. For this detection, the UVW phase of the PM motor is released (power supply is cut off), the rotor is rotated by applying torque from the outside, and a no-load line voltage corresponding to the rotation speed is generated at the winding terminal. Induced voltage detector 3
In a star connection configuration with the same resistance and connected between the winding terminals.

The comparator 4 compares the level of the induced voltage for one phase with the neutral point potential (0 V) of the star connection among the induced voltages detected by the induced voltage detector 3, thereby obtaining
Detects the zero cross point. The edge detection circuit 5 obtains a timing signal having a zero cross detected by the comparator 4 as an edge.

The position signal edge detection circuit 6 detects a falling edge of the phase waveform detected by the position sensor 2 as an edge signal. The phase waveform from the position sensor 2 becomes a saw-tooth waveform that repeats from 0 to 360 degrees, and the falling edge of this waveform is detected by the detection circuit 6 as an edge timing signal.

The offset adjusting circuit 7 adjusts the phase of the edge timing signal from the edge detecting circuit 6 according to the offset control signal. The offset adjustment control unit 8 calculates P
The edge timing signal of the square wave signal obtained from the induced voltage waveform of the M motor 1 is compared with the falling edge timing signal of the sawtooth waveform obtained from the position signal of the position sensor 2, and the timing difference between the two signals is obtained. Is detected, and the offset adjustment circuit 7 is set in a direction in which the “shift time” becomes zero.
, And finally, the time lag between the two edge timing signals is reduced to zero.

The motor control unit 9 stores the offset amount controlled by the offset adjustment control unit 8 in a nonvolatile memory such as a flash memory, and uses the offset amount when controlling the PM motor to determine the amount of displacement of the mounting position of the position sensor 2. Control is performed to correct the phase signal.

With the above configuration, the phase adjustment for controlling the PM motor can be achieved by mounting the position sensor 2 at an appropriate angle. In other words, it is not necessary to mount the oscilloscope while observing the waveform with a conventional oscilloscope, which is necessary for the conventional phase adjustment.

Offset adjustment controller 8 and motor controller 9
Is composed of a hardware configuration or a microcomputer and its software. In the case of a control device that controls the PM motor by a microcomputer, the software configuration of the offset adjustment control unit 8 and the offset adjustment circuit 7 is realized by the processing flow of FIG. 2 or FIG.

FIG. 2 starts with an interruption cycle of the microcomputer, fetches an edge signal A by an induced voltage from the edge detection circuit 5 (S1), and subsequently, a falling edge signal of a phase waveform passed through the offset adjustment circuit 7. B is fetched (S2). If both edge signals A and B cannot be fetched (detected) in the same interrupt cycle, the process returns to the detection of the edge signal in the next interrupt cycle (S2)
3).

In the same interrupt cycle, the edge signal A
Is detected and the edge signal B is not detected, the offset control signal is incremented (+1) (S
4). By performing such repetitive control, when both edge signals A and B are detected within the same interrupt cycle, the automatic phase adjustment ends (S5).

In the automatic phase adjustment by the above processing, as shown in the timing chart of FIG. 3, the offset control signal is incremented every interrupt signal cycle until both edges A and B are detected within the interrupt signal cycle. As a result, the edge signal B approaches the edge signal A, and finally, when the edges A and B are detected within the same interrupt cycle, the phase adjustment is terminated. Note that the timing error between the edges A and B is an interrupt cycle at the maximum, and the interrupt cycle is extremely high with respect to the electric angular velocity of the motor, so that the accuracy is extremely high.

FIG. 4 shows a case where the phase is adjusted by using the timer function. A circuit for detecting the number of revolutions of the motor using the position sensor 2 is provided. Starting at an interrupt cycle, an edge signal A based on an induced voltage from the edge detection circuit 5 is fetched (S11). When the detection is successful, a counter timer is started (S12) and the phase waveform passed through the offset adjustment circuit 7 is changed. Processing S until the falling edge signal B is detected
The process returns to 1 (S13), and the timer is stopped when the edge signal B is detected (S14).

Then, a phase amount is calculated from the count number of the timer and the motor rotation speed from the detection of the edge signal A to the detection of the edge signal B (S15). Note that the phase amount (ra
d) can be obtained as the number of rotations (rad / s) × timer time (s). The phase adjustment is completed using the calculated phase amount as an offset amount (S16).

In the automatic phase adjustment by the above processing, as shown in the timing chart of FIG. 5, the timer is started from the detection of the edge A, the timer is stopped by the detection of the edge B, and the count value during that time is changed to the edge A. , B can be obtained as an offset control amount.
In this case, the configuration can be such that the offset adjustment control by the offset adjustment circuit 7 is omitted.

[0025]

As described above, according to the present invention, the difference between the induced voltage of the PM motor and the phase signal of the position sensor is detected from the waveform signals, and the value that makes this difference zero is obtained as the offset amount. Since the phase is adjusted by storing the offset amount as a correction amount in motor control, accurate phase adjustment can be performed without the need for adjustment using an oscilloscope.

[Brief description of the drawings]

FIG. 1 is an apparatus configuration diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart of a phase adjustment process in the embodiment.

FIG. 3 is a phase adjustment timing chart in FIG. 2;

FIG. 4 is a flowchart of a phase adjustment process in the embodiment.

FIG. 5 is a phase adjustment timing chart in FIG. 4;

FIG. 6 is a waveform diagram of a magnetic flux density and an induced voltage of a PM motor and a phase signal of a position sensor.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 PM motor 2 Position sensor 3 Induced voltage detector 4 Comparator 5 Edge detection circuit 6 Position signal edge detection circuit 7 Offset adjustment circuit 8 Offset adjustment control unit 9 Motor control unit

[Procedure amendment]

[Submission date] October 10, 2000 (2000.10.
10)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Name of invention

[Correction method] Change

[Correction contents]

[Title of the Invention] Automatic phase adjustment device for PM motor

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a PM motor by a position sensor such as an encoder or a resolver.
Position in the initial process of attaching the position sensor
The present invention relates to an automatic phase adjustment device that automatically detects and adjusts the relationship (phase) between a signal and a winding position .

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction contents]

[0004] The positional relationship between the magnets of the PM motor can be obtained from a position sensor attached to the PM motor. When the position sensor is attached to the shaft of the PM motor, the PM motor is rotated without load from the outside, and the position of the UVW phase is detected. the induced voltage waveform and an output waveform of the position sensor is measured with an oscilloscope, 0 position sensor that position related to the zero-cross point of an induced voltage
The mounting position of the position sensor is adjusted so that the points match .

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

SUMMARY OF THE INVENTION An object of the present invention is to provide a PM motor capable of performing accurate phase adjustment without requiring adjustment by an oscilloscope.
An automatic position adjusting device is provided.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

A position sensor of a control device for controlling the PM motor based on a phase signal from a position sensor provided on the PM motor.
Automatically detects and adjusts magnet position and winding position when mounting
The automatic phase adjusting apparatus for integer, means for detecting a zero-cross point of the waveform of induced voltage when rotating the PM motor with no load as the edge timing signal A, the P
Means for detecting, as an edge timing signal B, a falling edge of a phase waveform from a position sensor when the M motor is rotated ;
An offset adjusting means for detecting a timing shift with respect to the timing signal B, and a motor control means for controlling the PM motor by correcting the phase signal using the timing shift as an offset amount.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

Further, the offset adjusting means detects the edge timing signals A and B at a fixed period, and controls the offset adjustment amount of the signal B until both signals A are detected within the same period to reduce the offset amount. It is characterized by seeking.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

Further, the offset adjusting means measures a time from the detection of the edge timing signal A to the detection of the edge timing signal B, and obtains the offset amount from the time and the number of rotations of the motor. .

Claims (3)

[Claims] 1. A control device for controlling a PM motor based on a phase signal from a position sensor provided on the PM motor, wherein a zero-cross point of an induced voltage waveform when the PM motor is rotated with no load is edge-timed. Means for detecting as a signal A; means for detecting the fall of a phase waveform from the position sensor when the PM motor is rotated as an edge timing signal B; and means for passing the edge timing signal A and the offset adjusting means. Offset adjustment control means for detecting a timing deviation from the edge timing signal B; and motor control means for controlling the PM motor by correcting the phase signal using the timing deviation as an offset amount. Control device for PM motor. 2. The offset adjustment control means detects the edge timing signals A and B at a fixed period, and controls the offset adjustment amount of the signal B until both signals A are detected within the same period to control the offset amount. The control device for a PM motor according to claim 1, wherein? 3. The offset adjustment control means measures a time from the detection of the edge timing signal A to the detection of the edge timing signal B, and obtains the offset amount from the time and the number of rotations of the motor. The control device for a PM motor according to claim 1.