JP2010166714A - Controller and control system for rotating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid such a state that a current flows in a motor generator greatly differently from a desired value. <P>SOLUTION: A controller predicts a current which flows in a motor generator 10 in the case where the operation state of an inverter IV is set at each of voltage vectors V0-V7 (steps S10-S22). At this time, it excludes a voltage vector, which corresponds to a current that increases a magnetic flux in the direction of a magnetic pole in the vicinity of a switching point between the maximum torque control and weak field control, among these predicted currents, from the candidates for the operation states of the inverter IV (steps S16-S20). It selects a voltage vector, where the deviation between the predicted current and a command current becomes the maximum, among the left candidates, thereby operating the inverter IV. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a control device for a rotating machine that controls a control amount of the rotating machine by operating a power conversion circuit including a switching element that electrically connects each of a positive electrode and a negative electrode of a DC power source to a terminal of the rotating machine, and It relates to the control system.

  This type of control device calculates a command value (command voltage) of a voltage to be applied to each phase in order to feedback control the current flowing in each phase of the three-phase motor to a command value, A device that performs triangular wave comparison PWM control that operates an inverter switching element based on the size of a triangular wave carrier has also been put into practical use. Thereby, the voltage applied to each phase of the three-phase motor can be used as a command voltage, and the current flowing through each phase can be controlled as desired.

  However, in the high rotation speed region of the three-phase motor, the command voltage rises and the amplitude becomes “½” or more of the input voltage of the inverter, so that the actual output voltage of the inverter becomes the command voltage. Can not be. For this reason, the controllability of the triangular wave comparison PWM control deteriorates as the command voltage increases.

  Therefore, conventionally, as can be seen, for example, in Patent Document 1 below, when the controllability of the triangular wave comparison PWM control is lowered, the ON / OFF cycle of the switching element of the inverter and the rotation cycle of the electrical angle of the three-phase motor are substantially matched. Switching to so-called rectangular wave control has also been proposed. Here, it has also been proposed to switch from rectangular wave control to triangular wave comparison PWM control by causing the current flowing through the rotating machine to be a region in which the field is stronger than the command current curve in triangular wave comparison PWM control.

JP 2002-223590 A

  By the way, when performing rectangular wave control, normally, so-called field weakening control is performed in which the current in the d-axis direction is increased and the magnetic flux in the magnetic pole direction is reduced as the induced speed of the three-phase motor increases as the rotational speed increases. For this reason, it is switched to the triangular wave comparison PWM control as the necessity of the field weakening control decreases. However, when the magnetic flux is temporarily increased unnecessarily as in the above-described prior art and then the control shifts to the triangular wave comparison PWM control, the triangular wave comparison PWM control is performed after a wasteful current flows.

  Note that such a problem does not occur only in the switching control described above. In general, in the case of feedback control, the current is once deviated from a desired value so as to eliminate the deviation. Therefore, the controllability is not necessarily high in controlling the current to a desired value. For this reason, for example, the concern that the current flowing through the three-phase motor exceeds the maximum allowable current of the inverter cannot be eliminated.

  The present invention has been made to solve the above problems, and an object of the present invention is to operate a power conversion circuit including a switching element that electrically connects each of a positive electrode and a negative electrode of a DC power source to a terminal of a rotating machine. Thus, an object of the present invention is to provide a control device and a control system for a rotating machine that can suitably avoid a situation in which the current flowing through the rotating machine greatly deviates from a desired value when controlling the control amount of the rotating machine.

  Hereinafter, means for solving the above-described problems and the operation and effects thereof will be described.

  According to a first aspect of the present invention, there is provided a rotating machine that controls a control amount of the rotating machine by operating a power conversion circuit including a switching element that electrically connects each of a positive electrode and a negative electrode of a DC power source to a terminal of the rotating machine. In the control device, the current prediction means for predicting the current flowing through the rotating machine when the operation state of the power conversion circuit is set, and the actual operation state of the power conversion circuit is within an allowable range of the predicted current. And avoiding means for avoiding an operation state corresponding to a part that deviates from the above.

  In the above invention, by providing the current predicting means, it is possible to predict the current flowing through the rotating machine in a predetermined operation state before actually operating the power conversion circuit. Then, by operating the power conversion circuit so that the predicted current does not correspond to the operation state corresponding to that outside the allowable range, it is possible to suitably avoid the situation where the current flowing through the rotating machine greatly deviates from a desired value. it can.

  According to a second aspect of the present invention, in the first aspect of the invention, the current predicting unit predicts a current flowing through the rotating machine when the operation state of the power conversion circuit is set to a plurality of types. It is characterized by doing.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein the rotating machine is a synchronous rotating machine, and a norm of an output voltage vector of the power conversion circuit corresponds to a predetermined low voltage region. In some cases, the first control means for operating the power conversion circuit so that the current flowing through the rotating machine becomes a command current, and the norm of the output voltage vector of the power conversion circuit corresponds to a predetermined high voltage region. In some cases, it further comprises second control means for operating the power conversion circuit so as to weaken the magnetic flux in the magnetic pole direction with respect to the command current of the first control means, and the avoidance means is based on the prediction by the current prediction means In the vicinity of the switching region between the first control means and the second control means, an operation state that is predicted to be a current that increases the magnetic flux in the magnetic pole direction more than the command current by the first control means is avoided. And wherein the door.

  Flowing a current that enhances the magnetic flux in the magnetic pole direction more than the command current from the first control means in the vicinity of the switching region means flowing a useless current to the rotating machine. In the above-mentioned invention, in view of this point, it is possible to preferably avoid a wasteful current from flowing through the rotating machine by avoiding an operation state that is predicted to cause such a current to flow.

  The vicinity of the switching region may be a region in which the command current from the first control unit is centered on a value corresponding to the upper limit value that can be realized by the input voltage of the power conversion circuit, and the degree of deviation from the center is a predetermined value or less. . Moreover, it is good also as an area | region used as the voltage utilization factor more than predetermined.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects of the present invention, the avoidance means is configured such that the current predicted by the current prediction means is a maximum allowable current of a switching element of the power conversion circuit. The actual operation state of the power conversion circuit is set while avoiding the operation state corresponding to the above.

  In the above invention, since it is possible to preferably avoid the current exceeding the maximum allowable current flowing through the switching element, it is possible to avoid a decrease in the reliability of the power conversion circuit or a forced shutdown process of the power conversion circuit. You can do it.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, further comprising means for calculating a state quantity of the rotating machine based on the current predicted by the current prediction means, and the avoidance The means avoids the operation state corresponding to the calculated state quantity not satisfying the predetermined constraint, thereby corresponding to the predicted current deviating from the allowable range corresponding to the constraint. It is characterized by avoiding an operation state.

  If the current of the rotating machine is predicted, other state quantities of the rotating machine can be predicted. And various restrictions may arise also in these other state quantities. In the above invention, in view of this point, the allowable range of the current is indirectly set by restrictions on other state quantities.

  The invention according to claim 6 is the invention according to claim 5, wherein the state quantity is a magnetic flux of the rotating machine.

  Since the magnetic flux is a parameter that determines the torque and the induced voltage, restrictions may be imposed on this. In this regard, in the above invention, by providing the avoidance means, it is possible to preferably avoid control that deviates from this restriction.

  A seventh aspect of the present invention is a rotating machine control system comprising the rotating machine control device according to any one of the first to sixth aspects and the power conversion circuit.

  In the above invention, by providing the avoidance means, it is possible to suitably avoid a situation in which the current flowing through the rotating machine greatly deviates from a desired value, and thus a highly reliable system is realized.

1 is a system configuration diagram according to a first embodiment. FIG. The figure which shows the setting of the command electric current concerning the embodiment. The figure which shows a voltage vector. The flowchart which shows the procedure of the process regarding operation of the inverter concerning the said embodiment. The flowchart which shows the procedure of the process regarding operation of the inverter concerning 2nd Embodiment. The flowchart which shows the procedure of the process regarding operation of the inverter concerning 3rd Embodiment.

(First embodiment)
Hereinafter, a first embodiment in which a control device for a rotating machine according to the present invention is applied to a control device for a hybrid vehicle will be described with reference to the drawings.

  FIG. 1 shows the overall configuration of a motor generator control system according to this embodiment. The motor generator 10 is a three-phase permanent magnet synchronous motor. The motor generator 10 is a rotating machine (saliency pole machine) having saliency. Specifically, the motor generator 10 is an embedded magnet synchronous motor (IPMSM).

  The motor generator 10 is connected to a high voltage battery 12 via an inverter IV and a boost converter CV. Here, the boost converter CV boosts the voltage (for example, “288V”) of the high-voltage battery 12 up to a predetermined voltage (for example, “666V”). On the other hand, the inverter IV includes a series connection body of the switching elements Sup and Sun, a series connection body of the switching elements Svp and Svn, and a series connection body of the switching elements Swp and Swn. The points are connected to the U, V, and W phases of the motor generator 10, respectively. In the present embodiment, insulated gate bipolar transistors (IGBTs) are used as the switching elements Sup, Sun, Svp, Svn, Swp, and Swn. In addition, diodes Dup, Dun, Dvp, Dvn, Dwp, and Dwn are connected in antiparallel to these.

  In this embodiment, the following is provided as detection means for detecting the state of the motor generator 10 and the inverter IV. First, a rotation angle sensor 15 that detects a rotation angle θ (electrical angle) of the motor generator 10 is provided. Further, current sensors 16, 17, and 18 that detect currents iu, iv, and iw flowing through the phases of the motor generator 10 are provided. Furthermore, a voltage sensor 19 for detecting an input voltage (power supply voltage VDC) of the inverter IV is provided.

  The detection values of the various sensors are taken into the control device 14 constituting the low pressure system via the interface 13. The control device 14 generates and outputs an operation signal for operating the inverter IV and the converter CV based on the detection values of these various sensors. Here, the signals for operating the switching elements Sup, Sun, Svp, Svn, Swp, Swn of the inverter IV are the operation signals gup, gun, gvp, gvn, gwp, gwn. The signals for operating the two switching elements of the boost converter CV are the operation signals gup and gcn.

  The control device 14 operates the inverter IV so as to obtain a command current for realizing the required torque for the motor generator 10. FIG. 2 shows the setting of the command current according to this embodiment.

In FIG. 2, a one-dot chain line is a maximum torque curve showing a command current determined by the maximum torque control that realizes the maximum torque with the minimum current as the current of the rotating two-dimensional coordinate system (dq coordinate system). On the other hand, the broken line is a current limit ellipse indicating the upper limit value of the current that can be realized by the power supply voltage VDC and the electrical angular velocity ω. This is because the current vector (id, iq) when the norm of the output voltage vector (vd, vq) becomes the upper limit value corresponding to the power supply voltage VDC in the voltage equations shown in the following equations (c1) and (c2). It can be derived as a trajectory.
vd = (R + pLd) id−ωLqiq (c1)
vq = ωLdid (R + pLq) iq + ωΦ (c2)
Incidentally, in the above formulas (c1) and (c2), the electrical angular velocity ω, the differential operator p, the d-axis inductance Ld, the q-axis inductance Lq, and the armature flux linkage constant Φ are used.

  In FIG. 2, a two-dot chain line is an equal torque curve indicating a current that can generate the same torque as the torque at the intersection P between the maximum torque curve and the current limit ellipse. Here, on the side of the equal torque curve where the d-axis current is decreased from the intersection point P (the side where the negative d-axis current is increased), although it falls within the region surrounded by the current-limiting ellipse, the d-axis is greater than the intersection point P. The side on which the current is increased (the side on which the negative d-axis current is reduced) is out of the region surrounded by the current limiting ellipse. In other words, the side where the d-axis current is decreased from the intersection P can be realized by the power supply voltage VDC, but the side where the d-axis current is increased from the intersection P cannot be realized by the power supply voltage VDC. This is because the contribution of the induced voltage ωΦ to the d-axis voltage can be reduced by increasing the d-axis current negatively in the above formula (c2).

  In view of the above, in this embodiment, the command current is defined by a solid line. That is, when the point on the maximum torque curve for realizing the required torque is in the region within the current limit ellipse, the maximum torque curve is set as the command current, and when there is not, the d-axis direction of the equal torque curve The part that performs field-weakening control that weakens the magnetic flux is defined as a command current. Since the current limit ellipse depends on the power supply voltage VDC and the electrical angular velocity ω, the command current is variably set according to the power supply voltage VDC and the electrical angular velocity ω.

  In this embodiment, in order to control the current flowing through the motor generator 10 to the command current, the current flowing through the motor generator 10 is predicted when the operation state of the inverter IV is set, and the operation state in which this predicted current is close to the command current. Model predictive control for operating the inverter IV is performed so that Here, the operation state of the inverter IV will be described first.

  The operation state of the inverter IV can be expressed by eight voltage vectors shown in FIG. Here, for example, the voltage vector representing the operation state (indicated as “lower” in the figure) in which the low-potential side switching elements Sun, Svn, Swn are turned on is the voltage vector V0, and the high-potential side switching element A voltage vector representing an operation state (indicated as “upper” in the drawing) in which Sup, Svp, and Swp are turned on is a voltage vector V7. These voltage vectors V0 and V7 are for short-circuiting all phases of the motor generator 10 and are called zero vectors because the voltage applied to the motor generator 10 from the inverter IV becomes zero. On the other hand, the remaining six voltage vectors V1 to V6 are defined by an operation pattern in which switching elements that are turned on exist in both the upper arm and the lower arm, and are called non-zero vectors. Yes. As shown in FIG. 3B, the voltage vectors V1, V3, and V5 correspond to the positive sides of the U phase, the V phase, and the W phase, respectively.

  In this embodiment, when the operation state of the inverter IV is set to each of these eight voltage vectors V0 to V7, the current flowing through the motor generator 10 is predicted, and based on this, the voltage vector to be set to the actual operation state is selected.

  FIG. 4 shows a processing procedure of model predictive control according to the present embodiment. The process shown in FIG. 4 is repeatedly executed by the control device 14 at a predetermined cycle, for example.

In this series of processing, first, in step S10, the current current detection values id and iq are acquired. This process is a process for converting the actual currents iu, iv, and iw detected by the current sensors 16 to 18 into the actual currents id and iq by performing three-phase conversion. In subsequent step S12, parameter n specifying voltage vectors V0 to V7 is set to zero. In the subsequent step S14, the current when the initial value of the current is the actual current id, iq in step S10 and the operation state of the inverter IV is the voltage vector Vn is predicted (currents ide, iq are calculated). This is because the following equations (formulas (c3) and (c4)) obtained by solving the above formulas (c1) and (c2) with respect to the differential term of the current are discretized and the current one step ahead is predicted. It can be carried out.
pid
= − (R / Ld) id + ω (Lq / Ld) iq + vd / Ld (c3)
piq
= −ω (Ld / Lq) id− (Rd / Lq) iq + vq / Lq−ωΦ / Lq (c4)
Incidentally, here, the output voltage vector (vd, vq) is a zero vector when the zero vector (V0, V7) is selected as the operation state of the inverter IV, and when the non-zero vector is selected, The vector norm shown in FIG. 3B may be the power supply voltage VDC, and this may be a vector obtained by dq conversion.

  In the subsequent step S16, it is determined whether or not it is in the vicinity of the intersection P between the equal torque curve Le and the maximum torque curve Lm corresponding to the power supply voltage VDC. This process determines whether or not the next operation of the inverter IV is a region where switching between maximum torque control and field weakening control may be required. Here, the vicinity of the intersection point P may be a region whose distance from the intersection point is not more than a predetermined value. Alternatively, it may be a region having a voltage utilization factor of a predetermined value or more (a voltage utilization factor at the time of the intersection P or a voltage utilization factor of a voltage utilization factor that is slightly smaller than this). In this case, the field-weakening control region includes a region in which the d-axis current is greatly reduced from the intersection point P. However, a simple determination can be made without causing any trouble due to the processing in step S18 described later. It becomes possible.

  If it is determined in the above step S16 that it is near the intersection, it is determined in step S18 whether or not the predicted currents ide and iqe are on the side that increases the d-axis current with respect to the maximum torque curve Lm. In other words, it is determined whether or not the maximum torque curve Lm is on the side of increasing the magnetic flux in the magnetic pole direction. If an affirmative determination is made in step S18, voltage vector Vn is excluded from candidates for the operating state of inverter IV in step S20.

  When the process of step S20 is completed or when a negative determination is made in steps S16 and S18, it is determined in step S22 whether or not the parameter n is “7”. This process is for determining whether or not the prediction of the current when all of the voltage vectors V0 to V7 are in the operation state of the inverter IV is completed. If a negative determination is made in step S22, the parameter n is incremented by “1” in step S24, and the process proceeds to step S14.

  When it is determined in step S22 that the parameter n is “7”, in step S26, a voltage vector that minimizes the deviation between the command current and the predicted current among the candidates for the operation state of the inverter IV is determined. Then, the operation state of the inverter IV is determined, and the inverter IV is operated so that the actual operation state of the inverter IV becomes this voltage vector.

  In addition, when the process of step S26 is completed, this series of processes is once complete | finished.

  According to the embodiment described in detail above, the following effects can be obtained.

  (1) In the vicinity of the switching region between the maximum torque control and the field weakening control, the inverter IV is operated while avoiding the operation state predicted to be a current that increases the magnetic flux in the magnetic pole direction rather than the command current by the maximum torque control. Thereby, it is possible to suitably avoid a wasteful current flowing through motor generator 10.

  (2) The current flowing through the motor generator 10 is predicted for each of the case where the operation state of the inverter IV is set to each of the non-zero vectors and the case where the operation state is set to the zero vector. Thereby, it is possible to search for an optimum state as the operation state of the inverter IV.

(Second Embodiment)
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  In the first embodiment, the inverter IV is operated while avoiding a voltage vector that increases the magnetic flux in the vicinity of the switching region between the maximum torque control and the field weakening control. On the other hand, in the present embodiment, the inverter IV is operated while avoiding that the current flowing through the inverter IV becomes a voltage vector that exceeds the allowable maximum current.

  FIG. 5 shows a processing procedure of model predictive control according to the present embodiment. The process shown in FIG. 5 is repeatedly executed by the control device 14 at a predetermined cycle, for example. In FIG. 5, processes corresponding to the processes shown in FIG. 4 are given the same step numbers for convenience.

  In this series of processes, after the process of step S14, in step S30, the predicted currents ide and iq are subjected to three-phase conversion to predict a three-phase current (iue, ive and iwe). In the subsequent step S32, it is determined whether or not the maximum value of these three-phase currents iue, ive, and iwe exceeds the threshold current Ith. Here, the threshold current Ith is the maximum allowable current of the inverter IV. Here, the maximum allowable current may be an upper limit value that can maintain the reliability of the inverter IV due to its structure. In addition, when a drive circuit that drives the inverter IV has a function of forcibly shutting down the inverter IV due to an excessively large current flowing through the inverter IV, a current that is not shut down. It is good also as an upper limit of. Thereby, the situation where inverter IV is actually shut down can be suitably avoided.

  According to the present embodiment described above, the following effects can be obtained in addition to the effect (2) of the first embodiment.

  (3) The actual operating state of the inverter IV was set avoiding the operating state corresponding to the predicted current exceeding the maximum allowable current of the switching element of the inverter IV. As a result, it is possible to suitably avoid the current exceeding the maximum allowable current flowing through the switching element, thereby avoiding a decrease in reliability of the inverter IV or avoiding a forced shutdown process of the inverter IV. be able to.

(Third embodiment)
Hereinafter, the third embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  In the present embodiment, the voltage ωφ due to the flux linkage is predicted based on the predicted currents ide and iqe, and the predicted voltage ωφ of the voltage vectors V0 to V7 is predicted to exceed the outputtable voltage of the inverter IV. Operate inverter IV to avoid things.

  FIG. 6 shows a processing procedure of model predictive control according to the present embodiment. The process shown in FIG. 6 is repeatedly executed by the control device 14 at a predetermined cycle, for example. In FIG. 6, processes corresponding to the processes shown in FIG. 4 are given the same step numbers for convenience.

  In this series of processes, when the process of step S14 is completed, the norm φ of the flux linkage vector is predicted based on the predicted currents ide and iqe in step S40. This process can be performed using the inductance of the motor generator 10. More specifically, a norm of a vector whose components are the second term on the right side of the above formula (c1) and the first term and the third term on the right side of the above formula (c2) is calculated and divided by the electrical angular velocity ω. What is necessary is just to do it.

  In subsequent step S42, it is determined whether or not the norm φ of the flux linkage vector is larger than a value obtained by dividing the threshold voltage Vth by the electrical angular velocity ω. This process is for determining whether or not the power running control can be realized by the power supply voltage VDC. Here, the threshold voltage Vth is the upper limit value of the norm of the output voltage vector (vector on the two-dimensional coordinate system) of the inverter IV that can be realized by the power supply voltage VDC. That is, the product of the norm of the flux linkage vector multiplied by the electrical angular velocity ω is equivalent to the voltage due to the magnetic flux, so that the power running control can be realized so that this voltage does not become larger than the voltage applied by the inverter IV. This is a condition.

  If a negative determination is made in step S42, the voltage vector Vn is excluded from candidates for the operation state of the inverter IV in step S20.

  According to the present embodiment described above, the following effects can be obtained in addition to the effect (2) of the first embodiment.

  (4) The voltage vector that causes the norm of the flux linkage vector of the motor generator 10 to exceed the value obtained by dividing the threshold voltage Vth determined from the power supply voltage VDC by the electrical angular velocity ω is excluded from the candidate operation states of the inverter IV. Thereby, the operation state in which powering control cannot be realized can be suitably eliminated.

(Other embodiments)
Each of the above embodiments may be modified as follows.

  The process for avoiding a specific voltage vector is not limited to performing any one of the processes exemplified in the first to third embodiments, and performs two or all of these three processes. It may be.

  In the third embodiment, the constraint on the norm φ of the flux linkage vector is set on the premise of powering control, but this is not restrictive, and a constraint may be set during regenerative control.

  In each of the above embodiments, the field-weakening control is performed because the maximum torque control is performed and the command current based on the maximum torque control cannot be realized by the input voltage of the inverter IV. For example, the field weakening control may be performed by performing the maximum efficiency control and the command current by the maximum efficiency control cannot be realized by the input voltage of the inverter IV. Further, for example, the field weakening control may be performed by performing control to make the current in the d-axis direction zero, and making it impossible to realize the command current by this control by the input voltage of the inverter IV.

  In the first embodiment, in the vicinity of the intersection P, the voltage predicted to increase the magnetic flux more than the maximum torque control both when the maximum torque control is performed and when the field weakening control is performed. Although the inverter IV was operated avoiding the vector, the present invention is not limited to this. For example, in the vicinity of the intersection P, avoid a voltage vector that is predicted to increase the magnetic flux more than the maximum torque control only when either the maximum torque control or the field weakening control is performed. The inverter IV may be operated.

  In the first embodiment, model prediction control is performed in the entire region, but the present invention is not limited to this. For example, model predictive control may be performed only during field weakening control, and triangular wave comparison PWM control may be performed for maximum torque control. Further, for example, the field weakening control may be performed as rectangular wave control, and the maximum torque control may be performed by model predictive control. Even in such a case, it is effective to operate the inverter IV in the vicinity of the switching point at which the model predictive control is switched to another control while avoiding the voltage vector predicted to increase the magnetic flux more than the maximum torque control. is there.

  Further, for example, in the case where the maximum torque control is performed by the triangular wave comparison PWM control and the field weakening control is performed by the rectangular wave control without using any model predictive control, in the vicinity of these switching points, the voltage vector specified by the current control is used. When it is predicted that the magnetic flux will be stronger than the maximum torque control, the control may be switched. Also by this, it is considered that the inverter IV can be operated while avoiding the voltage vector predicted to increase the magnetic flux more than the maximum torque control.

  The model predictive control is not limited to setting a voltage vector for setting the operation state of the inverter IV based on the prediction of current after one control cycle. For example, when setting a voltage vector in each of a plurality of control cycles, a voltage vector for operating the inverter IV in each of the plurality of control cycles is set based on prediction of a current flowing through the motor generator 10 in each control cycle. You may do.

  The model predictive control is not limited to predicting the current when each of the voltage vectors V0 to V7 that can be the operation state of the inverter IV is set as the operation state of the inverter IV. Each of the currents when set to a part of the current may be predicted.

  In each of the above embodiments, in the model predictive control, the voltage vector that minimizes the current deviation is selected to be the actual operation state of the inverter IV, but this is not limitative. For example, the sum of weighted values obtained by multiplying each of the current deviation and the switching frequency by a predetermined coefficient may be minimized as an evaluation function. Furthermore, the sum of the number of switching elements for switching the switching state at the time of switching the voltage vector and the current deviation multiplied by a predetermined coefficient may be minimized as an evaluation function.

  In such a case, the coefficient of the evaluation function may be learned and corrected according to the degree of divergence between the current actually realized by the voltage vector selected based on the evaluation function and the command current. As a result, for example, when the accumulated deviation degree is excessively large, the followability to the command current can be improved by performing a correction that relatively increases the weight to be multiplied by the current deviation.

  -The model used to predict the current is not limited to the model based on the fundamental wave. For example, a model including higher-order components for inductance and induced voltage may be used. The current predicting means is not limited to using a model formula, and may use a map. At this time, the input parameters of the map may be voltage (vd, vq) and electrical angular velocity ω, and may further include temperature and the like. Here, the map is storage means in which output parameter values corresponding to discrete values for input parameters are stored.

  The model used for predicting the current is not limited to a model that ignores iron loss, and may be a model that takes this into consideration.

  The control amount of the rotating machine is not limited to torque, and may be, for example, a rotational speed.

  The rotating machine is not limited to an embedded magnet synchronous machine, but may be an arbitrary synchronous machine such as a surface magnet synchronous machine or a field winding type synchronous machine. Furthermore, it is not limited to a synchronous machine, but may be an induction rotating machine such as an induction motor.

  -As a rotary machine, not only what is mounted in a hybrid vehicle but the thing mounted in an electric vehicle may be sufficient. Further, the rotating machine is not limited to the one used as the main machine of the vehicle.

  The DC power source is not limited to the converter CV but may be a high voltage battery 12. In other words, the input terminal of the inverter IV may be connected to the high voltage battery 12 without providing the converter CV.

  DESCRIPTION OF SYMBOLS 10 ... Motor generator, 12 ... High voltage battery, 14 ... Control apparatus (one Embodiment of the control apparatus of a rotary machine).

Claims (7)

In a control device for a rotating machine that controls a control amount of the rotating machine by operating a power conversion circuit including a switching element that electrically connects each of a positive electrode and a negative electrode of a DC power source to a terminal of the rotating machine,
Current prediction means for predicting the current flowing through the rotating machine when the operation state of the power conversion circuit is set;
A control device for a rotating machine comprising: avoiding means for avoiding an actual operation state of the power conversion circuit from becoming an operation state corresponding to a state in which the predicted current is out of an allowable range.   2. The control device for a rotating machine according to claim 1, wherein the current predicting unit predicts a current flowing through the rotating machine when the operation state of the power conversion circuit is set to a plurality of operating states. . The rotating machine is a synchronous rotating machine,
When the norm of the output voltage vector of the power conversion circuit corresponds to a predetermined low voltage region, first control means for operating the power conversion circuit so that the current flowing through the rotating machine becomes a command current;
When the norm of the output voltage vector of the power converter circuit corresponds to a predetermined high voltage region, the power converter circuit is operated so that the magnetic flux in the magnetic pole direction is weaker than the command current of the first control means. 2 control means,
Based on the prediction by the current prediction means, the avoidance means is a current that enhances the magnetic flux in the magnetic pole direction more than the command current by the first control means in the vicinity of the switching region between the first control means and the second control means. The control apparatus for a rotating machine according to claim 1, wherein a predicted operation state is avoided.   The avoiding means sets an actual operation state of the power conversion circuit while avoiding an operation state corresponding to a current predicted by the current prediction means exceeding a maximum allowable current of a switching element of the power conversion circuit. The control apparatus of the rotary machine of any one of Claims 1-3 characterized by these. Means for calculating a state quantity of the rotating machine based on the current predicted by the current prediction means;
The avoiding means avoids the calculated state quantity becoming an operation state corresponding to a state that does not satisfy a predetermined constraint, so that the predicted current deviates from an allowable range corresponding to the constraint. The control device for a rotating machine according to any one of claims 1 to 4, wherein a corresponding operation state is avoided.   The control device for a rotating machine according to claim 5, wherein the state quantity is a magnetic flux of the rotating machine. A control device for a rotating machine according to any one of claims 1 to 6,
A control system for a rotating machine comprising the power conversion circuit.

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