JP2013198342A - Controller for rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which the output voltage of an inverter INV decreases in precision because of restrictions for reducing electromagnetic noise generated due to an ON/OFF operation of a switching element S¥# constituting the inverter INV.SOLUTION: A PWM processing section 40 generates an operation signal g¥# for making the output voltage of an inverter INV into command voltages vu*, vv*, and vw* and outputs the operation signal g¥# to the inverter INV. Here, the generation processing of the operation signal g¥# is PWM processing. This is carried out using a carrier signal Sc of an asynchronous carrier generation section 42 or a synchronous carrier generation section 46. When a value obtained by adding an electric angular frequency to the double of a carrier frequency is a prescribed frequency in asynchronous PWM processing based upon the carrier signal Sc of the asynchronous carrier generation section 42, the processing is switched to synchronous PWM processing based upon the carrier signal SC of the synchronous carrier generation section 46 to lower the carrier frequency.

Description

  The present invention relates to a rotating machine that controls a control amount of the rotating machine by operating a DC / AC converter circuit including a switching element that opens and closes between each terminal of the rotating machine and each of a positive electrode and a negative electrode of a DC voltage source. The present invention relates to a control device.

  This type of control device performs PWM processing for generating an operation signal of an inverter in accordance with a magnitude comparison between a carrier and a command value in a time period so that an output voltage of a DC / AC converter circuit (inverter) is a command value. There are also things. In this case, if one cycle of the output voltage of the inverter is not sufficiently large as compared with one cycle of the carrier, an error with respect to the command value of the output voltage of the inverter becomes large. Therefore, conventionally, for example, as described in Patent Document 1 below, in a situation where the cycle of the output voltage is shortened, it is also proposed to switch to synchronous PWM processing in which one cycle of the carrier is set to 1 / integer of the cycle of the output voltage. Has been.

Japanese Patent No. 4205157

  By the way, electromagnetic noise occurs due to the on / off operation of the switching elements constituting the inverter. When this noise becomes excessively large, there is a concern that the reliability of the inverter control device is lowered. On the other hand, in the case of the above-mentioned device, although the controllability of the output voltage can be improved, it cannot be said that it is necessarily sufficient as a countermeasure against electromagnetic noise.

  The present invention has been made in the process of solving the above-described problems, and an object of the present invention is to provide a DC / AC conversion circuit including a switching element that opens and closes between each terminal of a rotating machine and each of a positive electrode and a negative electrode of a DC voltage source. Is to provide a new control device for a rotating machine that controls the control amount of the rotating machine.

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

  The invention according to claim 1 operates a DC / AC conversion circuit (INV) including a switching element that opens and closes between each terminal of the rotating machine (10) and each of the positive electrode and the negative electrode of the DC voltage source (CNV). And operating means (30) for controlling the control amount of the rotating machine, wherein the operating means controls the output voltage of the DC / AC converter circuit to control the control amount of the rotating machine. Asynchronous control means for switching a switching state of the switching element at random with respect to a voltage cycle, and depending on a power supply angular frequency that is a frequency of the output voltage among electromagnetic noises accompanying operation of the switching element by the asynchronous control means. And avoiding means for avoiding that the maximum frequency becomes a specified frequency or more and the maximum value becomes a specified value or more. To.

  Although the electromagnetic noise caused by the switching of the switching element is caused by the switching frequency, the inventors have found that, strictly speaking, there is a component that becomes a maximum value separated from this frequency by a frequency corresponding to the power supply angular frequency. Has been. Here, when the switching frequency is sufficiently larger than the power supply angular frequency, this component is slightly different from the switching frequency. Then, it is an approximation that this noise depends only on the switching frequency. If the switching frequency is set to a high frequency as much as possible in order to improve the controllability of the output voltage while avoiding the specified frequency, this noise is actually There is a risk of applying the specified frequency. In view of this point, the above invention provides an avoidance means.

  The invention according to claim 8 operates a DC / AC conversion circuit (INV) including a switching element that opens and closes between each terminal of the rotating machine (10) and each of the positive electrode and the negative electrode of the DC voltage source (CNV). And operating means (30) for controlling the control amount of the rotating machine, the operating means for operating the output voltage of the DC / AC converter circuit to control the control amount of the rotating machine. Asynchronous control means for switching the switching state of the switching element at random with respect to the period of the current flowing through the terminal of the machine, and to manipulate the output voltage of the DC-AC converter circuit to control the control amount of the rotating machine, Synchronous control means for switching a switching state of the switching element in synchronization with a cycle of a current flowing through a terminal of the rotating machine or a cycle of an integer thereof; and the asynchronous Switching means for switching from control by the control means to control by the synchronous control means, the switching means receives at least one of the torque of the rotating machine, the output current of the DC / AC converter circuit, and the input voltage, The switching is performed.

  The torque of the rotating machine, the output current of the DC / AC converter circuit, and the input voltage are parameters that correlate with the switching loss of the switching elements constituting the DC / AC converter circuit and electromagnetic noise accompanying switching. Here, when the switching loss and electromagnetic noise increase during the control by the asynchronous control means, if the switching frequency is lowered, the switching loss can be reduced or the peak frequency of the electromagnetic noise can be reduced. In this case, the controllability of the output voltage is lowered. On the other hand, by using the synchronous control means, it is possible to alleviate the decrease in the controllability of the output voltage while reducing the switching frequency as compared with the case of using the asynchronous control means. In the above invention, in view of this point, switching from the control by the asynchronous control means to the control by the synchronous control means is performed based on the parameter having a correlation with the switching loss.

  In addition, about the expansion of the concept regarding the following typical embodiment concerning this invention, it describes in the column of "other embodiment" after typical embodiment.

1 is a system configuration diagram according to a first embodiment. FIG. The figure which shows the operation area | region of the motor generator concerning the embodiment. The figure which shows the electromagnetic noise produced by the asynchronous PWM process of the embodiment. 6 is a flowchart showing a procedure of switching processing to synchronous PWM processing according to the embodiment; The flowchart which shows the procedure of the switching process to the synchronous PWM process concerning 2nd Embodiment. The flowchart which shows the procedure of the switching process to the synchronous PWM process concerning 3rd Embodiment. The flowchart which shows the procedure of the switching process to the synchronous PWM process concerning 4th Embodiment. The flowchart which shows the procedure of the switching process to the synchronous PWM process concerning 5th Embodiment. The system block diagram concerning 6th 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 rotating machine as an in-vehicle main machine will be described with reference to the drawings.

  A motor generator 10 shown in FIG. 1 is an in-vehicle main machine, and is mechanically coupled to drive wheels (not shown). Motor generator 10 is connected to high voltage battery 12 via inverter INV and boost converter CNV. Here, boost converter CNV includes a capacitor 16, a pair of switching elements Scp and Scn connected in parallel to capacitor 16, and a reactor that connects a connection point between the pair of switching elements Scp and Scn and the positive electrode of high voltage battery 12. 14. The voltage of the high voltage battery 12 (for example, 100 V or more) is boosted up to a predetermined voltage (for example, “666 V”) by turning on / off the switching elements Scp, Scn.

  On the other hand, the inverter INV 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, an insulated gate bipolar transistor (IGBT) is used as these switching elements S ¥ # (¥ = u, v, w, c; # = p, n). In addition, a diode D ¥ # is connected in antiparallel to each of these.

  The control device 30 is a device that controls the control amount of the motor generator 10 by operating the inverter INV and the converter CNV. In the figure, among the processes performed by the control device 30, processes related to control of the control amount of the motor generator 10 are shown in a block diagram.

  That is, the command current setting unit 32 sets the command currents id * and iq * based on the torque command value Trq *. Here, the current for performing the minimum current / maximum torque control is set as the command value. On the other hand, the rotating coordinate conversion unit 34 converts the phase currents iu, iv, iw detected by the current sensor 22 into actual currents id, iq on the dq axis. The current controller 36 calculates the command voltage vd * as an operation amount for feedback control of the actual current id to the command current id *, and as an operation amount for feedback control of the actual current iq to the command current iq *. The command voltage vq * is calculated.

  The three-phase fixed coordinate conversion unit 38 converts the command voltages vd * and vq * into three-phase command voltages vu *, vv * and vw *.

  The PWM processing unit 40 generates an operation signal g ¥ # for setting the output voltage of the inverter INV to the command voltages vu *, vv *, vw * and outputs the operation signal g ¥ # to the inverter INV. The generation process of the operation signal g ¥ # here is a PWM process. This is performed using the carrier wave (carrier signal Sc) of the asynchronous carrier generation unit 42 or the synchronous carrier generation unit 46. In the present embodiment, the carrier signal Sc is a triangular wave in which the gradually increasing speed and the gradually decreasing speed are equal.

  The asynchronous carrier generation unit 42 generates a carrier signal Sc having a predetermined time period. On the other hand, in the synchronous carrier generation unit 46, one electrical angle period is calculated based on the rotation speed (the output value of the speed calculation unit 44) as a time differential value of the rotation angle θ detected by the rotation angle sensor 20. The carrier signal Sc is generated so as to be an integral multiple of the period. Which carrier signal Sc of the asynchronous carrier generation unit 46 and the synchronous carrier generation unit 46 is used is switched by the selector 48.

  In the PWM processing unit 40, first, the command voltage v ¥ * is normalized by the input voltage (power supply voltage VDC) of the inverter INV detected by the voltage sensor 24, thereby generating the Duty signal D ¥ *. Next, the PWM signal g ¥ is generated based on the magnitude comparison between the duty signal D ¥ * and the carrier signal Sc. A signal obtained by delaying the rising edge of the PWM signal g ¥ by the dead time is defined as an upper arm operation signal g ¥ p. Further, a signal obtained by delaying the rising edge of the logical inversion signal of the PWM signal g ¥ by the dead time is referred to as a lower arm operation signal g ¥ n.

  In the present embodiment, the sampling period of the detection value of the current sensor 22 and the update period of the command voltage v ¥ # are set as the period of the carrier signal Sc.

  FIG. 2 shows an operation region of the motor generator 10 according to the present embodiment. Here, the vertical axis is the torque Trq and the horizontal axis is the electrical angular velocity ω. As shown in the figure, in the region where the electrical angular velocity ω is relatively low, the maximum value of the torque Trq is a constant value. This maximum value is determined by the allowable maximum current of the switching element S ¥ # constituting the inverter INV. On the other hand, in the region where the electrical angular velocity ω is high, the torque Trq decreases as the electrical angular velocity ω increases. This corresponds to the fact that the maximum value of the torque Trq that can be generated by the voltage that can be output from the inverter INV decreases as the electrical angular velocity ω increases. In a region where the rotational speed is high to some extent, well-known field weakening control or the like is performed, but the description as a block diagram in FIG. 1 is omitted.

  Here, the carrier signal Sc of the asynchronous carrier generation unit 42 is used in the low rotation speed region, and the carrier signal Sc of the synchronous carrier generation unit 46 is used in the high rotation speed region. Here, the switching to the carrier signal Sc of the synchronous carrier generation unit 46 is normally caused by the difference between the cycle of the carrier signal Sc of the asynchronous carrier generation unit 42 and one electrical angle cycle being reduced. # Is made when the accuracy of simulating the command voltage v ¥ * decreases. However, in this embodiment, the synchronous carrier generation unit 46 switches to the carrier signal Sc for a different use. This will be described below.

  FIG. 3 shows a primary component of electromagnetic noise generated by the on / off operation of the switching element S ¥ # constituting the inverter INV. As shown in the figure, the primary components of the electromagnetic noise are “2 · (fc−ω / 2π)” and “2 · (fc + ω), which are frequencies slightly separated from the frequency of the carrier signal Sc (carrier frequency fc). / 2π) ”, the maximum component occurs. This is noise that occurs in the vicinity of the frequency “2 · fc” depending on the electrical angular velocity ω, and is hereinafter referred to as speed-dependent noise.

  The frequency of the speed-dependent noise has a very small frequency difference from the frequency “2 · fc” corresponding to the carrier frequency fc, and is usually 1 or less of the carrier frequency fc. However, the speed-dependent noise can be a great limitation in the design of the control process of the motor generator 10 in order to satisfy the request for making the predetermined frequency noise below the specified value, such as noise regulation.

  That is, for example, as shown in FIG. 3, it is assumed that the upper limit value of the magnitude of electromagnetic noise having a specified frequency f1 or higher is severely restricted. In the following, it is assumed that the specified frequency f1 is “9 kHz”. By the way, in order to control the output voltage of the inverter INV to the command voltage v ¥ * with high accuracy, the carrier frequency fc of the carrier signal Sc of the asynchronous carrier generator 42 is preferably as high as possible. Here, when the carrier frequency fc is set to “4.1 to 4.4 kHz”, in the approximation in which the frequency at which the noise caused by switching is maximized is regarded as “2 · fc”, the electromagnetic noise having the specified frequency f1 or more is considered. It is possible to satisfy the constraints. However, even in this case, the speed-dependent noise having the frequency “2 · (fc + ω / 2π)” may not satisfy the restriction on the electromagnetic noise having the specified frequency f1 or higher. That is, for example, it is assumed that the electrical angular frequency “ω / 2π” in the region using the carrier signal Sc of the asynchronous carrier generation unit 42 is at most “400 Hz”. However, even in this case, the speed-dependent noise having the frequency “2 · (fc + ω / 2π)” may not satisfy the restriction on the electromagnetic noise having the specified frequency f1 or higher.

  Therefore, in the present embodiment, the carrier frequency fc is reduced according to the electrical angular velocity ω so that the speed-dependent noise of the frequency “2 · (fc + ω / 2π)” does not conflict with the restriction on the electromagnetic noise of the specified frequency f1 or higher. At this time, the carrier signal Sc of the asynchronous carrier generation unit 42 is switched to the carrier signal Sc of the synchronous carrier generation unit 46. This is a setting for suppressing as much as possible the situation in which the accuracy with which the output voltage of the inverter INV simulates the command voltage v ¥ * is lowered. That is, when the carrier frequency Sc of the carrier signal Sc of the asynchronous carrier generation unit 42 is decreased, the output voltage of the inverter INV causes a decrease in accuracy of simulating the command voltage v ¥ *, but the carrier of the synchronous carrier generation unit 46 By switching to the signal Sc, it is possible to suppress a decrease in the accuracy to be simulated due to a decrease in the carrier frequency fc.

  In FIG. 4, from PWM processing (asynchronous PWM processing) using the carrier signal Sc of the asynchronous carrier generation unit 42 according to the present embodiment, to PWM processing (synchronous PWM processing) using the carrier signal Sc of the synchronous carrier generation unit 46. The procedure of the switching process is shown. This process is repeatedly executed by the control device 30 at a predetermined cycle, for example.

  In this series of processing, first, in step S10, it is determined whether or not asynchronous PWM processing is performed. When an affirmative determination is made in step S10, it is determined in step S12 whether or not the electrical angular velocity ω is equal to or higher than the threshold velocity ωth. This process is for determining whether or not the speed-dependent noise at the frequency “2 · (fc + ω / 2π)” may violate the restriction on the electromagnetic noise having the specified frequency f1 or higher. Here, the threshold speed ωth is set to a value smaller than the electrical angular speed ω when the frequency “2 · (fc + ω / 2π)” becomes the specified frequency f1.

  When an affirmative determination is made in step S12, switching to synchronous PWM processing is performed in step S14. When the process of step S14 is completed or when a negative determination is made in steps S10 and S12, this series of processes is temporarily terminated.

As described above, in this embodiment, when it is determined that the speed-dependent noise of the frequency “2 · (fc + ω / 2π)” may violate the restriction on the electromagnetic noise having the specified frequency f1 or more, the synchronous PWM processing is performed. By switching and lowering the switching frequency, it is possible to sufficiently suppress a decrease in the accuracy of the output voltage of the inverter INV while avoiding a conflict situation. Incidentally, the reason why only the first-order noise is considered in the above is that the magnitude of the high-order noise is smaller than that of the first-order noise.
<Second Embodiment>
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  FIG. 5 shows a procedure of switching processing from the asynchronous PWM processing to the synchronous PWM processing according to the present embodiment. This process is repeatedly executed by the control device 30 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, if an affirmative determination is made in step S10, it is determined in step S20 whether or not the vector norm of the command currents id * and iq * is equal to or greater than a specified value Ith. This process is for determining whether or not the magnitude of the speed-dependent noise at the frequency “2 · (fc + ω / 2π)” is equal to or greater than a specified value. This is in view of the fact that the magnitude of the speed-dependent noise depends on the magnitude of the current cut off by turning on / off the switching element S ¥ #. The specified value Ith is set to be equal to or lower than a lower limit value at which the magnitude of the speed-dependent noise at the frequency “2 · (fc + ω / 2π)” is equal to or higher than the specified value.

  If a negative determination is made in step S20, it is determined in step S22 whether the power supply voltage VDC is equal to or higher than the threshold voltage Vth. This process is for determining whether or not the magnitude of the speed-dependent noise at the frequency “2 · (fc + ω / 2π)” is equal to or greater than a specified value. This is because the magnitude of the speed-dependent noise depends on the magnitude of the voltage applied between the ends (collector and emitter) of the flow path when switching the switching state of the switching element S ¥ #. Is. The threshold voltage Vth is set to be equal to or lower than a lower limit value at which the magnitude of the speed-dependent noise at the frequency “2 · (fc + ω / 2π)” is equal to or higher than a specified value.

  If an affirmative determination is made in step S20 or step S22, the process proceeds to step S12. If an affirmative determination is made in step S12, the process proceeds to step S14. And when the process of step S14 is completed, or when negative determination is made in step S10, S12, S22, this series of processes is once complete | finished.

Thus, in the present embodiment, whether or not the magnitude of the speed-dependent noise at the frequency “2 · (fc + ω / 2π)” is equal to or greater than the specified value based on the magnitude of the power cut off by the switching element S ¥ #. By determining whether or not (steps S20 and S22), unnecessary switching to the synchronous PWM processing can be avoided from the viewpoint of suppressing electromagnetic noise.
<Third Embodiment>
Hereinafter, the third embodiment will be described with reference to the drawings with a focus on differences from the second embodiment.

  FIG. 6 shows the procedure of the switching process from the asynchronous PWM process to the synchronous PWM process according to the present embodiment. This process is repeatedly executed by the control device 30 at a predetermined cycle, for example. In FIG. 6, processes corresponding to the processes shown in FIG. 5 are given the same step numbers for convenience.

As shown in the figure, in this embodiment, when an affirmative determination is made in step S20 or step S22, the process switches to synchronous PWM processing in step S14. That is, in the present embodiment, when it is determined that the magnitude of the frequency “2 · (fc + ω / 2π)” is greater than the specified value without determining the frequency band of the speed-dependent noise, the synchronous PWM processing is performed. Switch. Here, even if the carrier frequency fc in the synchronous PWM processing becomes the maximum value of the electrical angular velocity ω in the region where the synchronous PWM processing is performed, the frequency “2 · (fc + ω / 2π)” is less than the specified frequency f1. Set to.
<Fourth Embodiment>
Hereinafter, the fourth embodiment will be described with reference to the drawings with a focus on differences from the third embodiment.

  FIG. 7 shows the procedure of the switching process from the asynchronous PWM process to the synchronous PWM process according to this embodiment. This process is repeatedly executed by the control device 30 at a predetermined cycle, for example. In FIG. 7, processes corresponding to the processes shown in FIG. 6 are given the same step numbers for convenience.

As shown in the figure, in this embodiment, when an affirmative determination is made in step S20, switching to synchronous PWM processing is performed in step S14. That is, also in the present embodiment, the synchronous PWM processing is performed when it is determined that the magnitude is equal to or greater than the predetermined value without determining the frequency band of the speed-dependent noise having the frequency “2 · (fc + ω / 2π)”. Switch to. Here, even if the carrier frequency fc in the synchronous PWM processing becomes the maximum value of the electrical angular velocity ω in the region where the synchronous PWM processing is performed, the frequency “2 · (fc + ω / 2π)” is less than the specified frequency f1. Set to.
<Fifth Embodiment>
Hereinafter, the fifth embodiment will be described with reference to the drawings with a focus on differences from the third embodiment.

  FIG. 8 shows a procedure of switching processing from the asynchronous PWM processing to the synchronous PWM processing according to the present embodiment. This process is repeatedly executed by the control device 30 at a predetermined cycle, for example. In FIG. 8, processes corresponding to the processes shown in FIG. 6 are given the same step numbers for convenience.

As shown in the figure, in the present embodiment, when an affirmative determination is made in step S20 or step S12, switching to synchronous PWM processing is performed in step S14. Here, even in a situation in which a negative determination is made in step S12, shifting to the synchronous PWM process when an affirmative determination is made in step S20 and reducing the switching frequency (carrier frequency fc) reduce the switching loss. Because. That is, when the current cut off by the switching element S ¥ # is large, not only the speed-dependent noise increases but also the switching loss increases. For this reason, in order to reduce the switching loss, if an affirmative determination is made in step S20, the process switches to synchronous PWM processing in step S14.
<Sixth Embodiment>
Hereinafter, the sixth embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  FIG. 9 shows a system configuration according to the present embodiment. In FIG. 9, the same reference numerals are given for the sake of convenience for members and processes corresponding to those shown in FIG. 1.

  The norm setting unit 50 uses a map storing the relationship between the torque command value Trq * and the electrical angular velocity ω and the norm Vn of the output voltage vector of the inverter INV, and inputs the torque command value Trq * and the electrical angular velocity ω to obtain the norm Vn. Set. Here, the norm of the vector is defined by the square root of the sum of the squares of the components of the vector. The norm Vn here is designed to satisfy the same requirements as the command currents id * and iq * set by the command current setting unit 32. That is, it is designed so that minimum current maximum torque control can be realized.

  The deviation calculation unit 52 calculates the difference between the q-axis actual current iq and the command current iq *.

  The phase setting unit 54 calculates the phase δ as an operation amount for performing feedback control of the q-axis actual current iq to the command current iq * based on the output value of the deviation calculation unit 52. This phase δ is calculated as the sum of the outputs of the proportional element and the integral element, which receives the difference between the actual current iq and the command current iq *.

  Then, in the pattern operation unit 56, based on the phase δ set by the phase setting unit 54, the norm Vn output by the norm setting unit 50, the power supply voltage VDC, and the rotation angle θ, the operation signals gup, gun, gvp , Gvn, gwp, and gwn. Specifically, the pattern operation unit 56 stores an operation signal waveform for one rotation period of the electrical angle as map data for each modulation rate.

  The pattern operation unit 56 calculates a modulation rate based on the power supply voltage VDC and the norm Vn, and selects a corresponding operation signal waveform accordingly. Here, the upper limit of the modulation rate is set to “1.27”, which is the modulation rate during rectangular wave control. For this reason, when the modulation factor becomes the maximum value “1.27”, the switching element Sup, Svp, Swp on the high potential side is used as the operation signal waveform in one rotation period of the electrical angle that is the waveform at the time of the rectangular wave control. A waveform (one pulse waveform) that occurs once each is selected for a pair of periods of a period in which the switching element Sun, Svn, Swn on the low potential side is turned on and a period in which the switching element Sun, Svn, Swn is turned on.

  When the operation signal waveform is selected in this way, the pattern operation unit 56 generates an operation signal by setting the output timing of this waveform based on the phase δ set by the phase setting unit 54.

  The switching unit 58 switches between using the operation signal g ¥ # of the PWM processing unit 40 and the operation signal g ¥ # of the pattern operation unit 56.

In such a configuration, in this embodiment, when an affirmative determination is made in step S12 of FIG. 4, the operation signal g ¥ # of the PWM processing unit 40 is switched to the operation signal g ¥ # of the pattern operation unit 56. Here, the operation signal waveform stored in the pattern operation unit 56 is preliminarily adapted so that the magnitude of the component in which the electromagnetic noise is equal to or higher than the specified frequency f1 can be reduced.
<Other embodiments>
Each of the above embodiments may be modified as follows.

About switching means
The parameter having a correlation with the power supply angular frequency is not limited to the electrical angular velocity ω of the synchronous machine, and may be, for example, the norm of the output voltage vector (vd *, vq *) of the inverter INV. This is because the norm of the output voltage vector increases because the induced voltage increases as the electrical angular velocity ω increases.

  In the previous second embodiment (FIG. 5), when an affirmative determination is made in any of steps S20, S22, and S12, the process may move to step S14 and be switched to synchronous PWM processing. However, in this case, the positive determination in steps S20 and S22 means that the switching loss is determined to increase.

  The determination means for determining whether or not the switching loss is increased by the synchronous PWM processing is not limited to the one exemplified in the fifth embodiment (FIG. 8). For example, when the logical product of the norm of the command current vector (id *, iq *) being equal to or greater than a specified value and the power supply voltage VDC being equal to or greater than the specified voltage is true, it is determined that the switching loss is increased. You may do. Note that the input parameters for obtaining information on the vector norm of the output current are not limited to the command currents id * and iq *, but may be actual currents id and iq, for example. Further, in view of the positive correlation between the absolute value of the q-axis component and the d-axis component of the output current vector and the absolute value of the output current, the magnitude of the q-axis current and the d-axis current May be the size. However, there is no positive correlation between the absolute value of the d-axis component of the output current vector and the absolute value of the output current, such as when performing minimum current maximum torque control using a surface magnet synchronous machine (SPMSM) as the rotating machine. In some cases, use of the magnitude of the d-axis current is avoided. Since there is also a positive correlation between the output current vector norm and the torque of motor generator 10, torque command value Trq * or estimated torque estimated based on current may be used.

  The process of step S20 of the fifth embodiment (FIG. 8) is a means for determining whether or not the switching loss is increased independently of the noise countermeasure of the specified frequency f1. Considering that the purpose of suppressing the increase in the switching loss is to limit the temperature rise of the switching element S ¥ #, even if an affirmative determination is made in step S20, the switching element S ¥ # When the temperature is low, a change without switching to the synchronous PWM processing is also possible.

  In the embodiment of the switching means described above, the switching frequency is switched to the synchronous PWM processing for the purpose of reducing the switching loss independently of the noise countermeasure of the specified frequency f1. As can be seen, it is apparent that the switching means can be configured to perform only the process of switching to the synchronous PWM process for the purpose of reducing the loss regardless of the noise countermeasure of the specified frequency f1. In this case, the switching is not limited to the synchronous PWM processing, and any switching loss can be used. However, if the controllability of the output voltage is reduced by switching, if the temperature of the switching element S ¥ # is not excessively high, the norm of the command current vector (id *, iq *) is not less than a specified value, Even if the power supply voltage VDC is equal to or higher than the specified voltage, it is desirable to prohibit switching to the synchronous PWM process when the electrical angular velocity is high.

"Asynchronous control means"
The update cycle of the command voltage v ¥ # (¥ = u, v, w; # = p, n) and the update cycle of the carrier signal Sc are not limited. For example, the update cycle of the command voltage v ¥ # may be shorter than the update cycle of the carrier signal Sc.

  The present invention is not limited to the comparison between the command voltage v ¥ # as the fundamental wave voltage and the carrier signal Sc. For example, the carrier signal Sc is compared in magnitude with the two-phase modulated command voltage v ¥ # as the fundamental wave voltage, or the third harmonic wave superimposed on the command voltage v ¥ # as the fundamental voltage It may be.

"Synchronous PWM processing means"
The update cycle of the command voltage v ¥ # (¥ = u, v, w; # = p, n) and the update cycle of the carrier signal Sc are not limited. For example, the update cycle of the command voltage v ¥ # may be shorter than the update cycle of the carrier signal Sc.

  The present invention is not limited to the comparison between the command voltage v ¥ # as the fundamental wave voltage and the carrier signal Sc. For example, the carrier signal Sc is compared in magnitude with the two-phase modulated command voltage v ¥ # as the fundamental wave voltage, or the third harmonic wave superimposed on the command voltage v ¥ # as the fundamental voltage It may be.

"About pattern waveform control means"
The present invention is not limited to operating the phase δ of the output voltage of the inverter INV in order to feedback control the actual current id on the q axis to the command current iq *. For example, the phase δ of the output voltage of the inverter INV may be manipulated so that the torque (estimated torque Trq) estimated by the actual currents id and iq is feedback-controlled to the torque command value Trq *.

"About rotating machines"
What is not limited to the IPMSM is as described in the section “Switching means”.

  Moreover, it is not restricted to a synchronous machine. However, when applied to an induction machine, it should be noted that the noise that should be avoided by the avoiding means is noise that is higher than the carrier frequency fc by the power supply angular frequency and not higher than the electrical angular frequency. Incidentally, in the synchronous machine, the electrical angular frequency and the power source angular frequency coincide.

  In addition, it is not restricted to a vehicle-mounted main machine, For example, the electric motor incorporated in the compressor in a vehicle-mounted air conditioner may be sufficient. Moreover, not only a three-phase rotating machine but a five-phase rotating machine may be used.

“About DC to AC converter (INV)”
Switching element S ¥ # is not limited to IGBT, and may be, for example, a MOS field effect transistor or the like. Further, the converter CNV is not limited to a DC voltage source, and the high voltage battery 12 may be a DC voltage source.

"others"
The current command value is not limited to that for realizing the minimum current maximum torque control.

  DESCRIPTION OF SYMBOLS 10 ... Motor generator, 42 ... Asynchronous carrier production | generation part, 46 ... Synchronous carrier production | generation part, INV ... Inverter.

Claims (8)

By operating a DC / AC converter circuit (INV) including a switching element that opens and closes between each terminal of the rotating machine (10) and the positive electrode and the negative electrode of the DC voltage source (CNV), the control amount of the rotating machine Operating means (30) for controlling
The operation means includes
Asynchronous control means for switching the switching state of the switching element at random with respect to the period of the output voltage in order to manipulate the output voltage of the DC / AC converter circuit in order to control the control amount of the rotating machine;
Of the electromagnetic noise associated with the operation of the switching element by the asynchronous control means, the frequency that becomes maximum depending on the power supply angular frequency that is the frequency of the output voltage is equal to or higher than the specified frequency, and the maximum value is the specified value. Avoidance means to avoid the above,
A control device for a rotating machine. The asynchronous control means performs the operation of the switching element by PWM processing,
2. The rotating machine control device according to claim 1, wherein the maximum frequency is twice the value obtained by adding the power source angular frequency to the carrier frequency of the PWM processing. The avoiding means is:
Synchronizing to switch the switching state of the switching element in synchronization with the period of the output voltage or a period of 1 / integer thereof in order to manipulate the output voltage of the DC / AC converter circuit to control the control amount of the rotating machine Control means;
Switching means for switching from control by the asynchronous control means to control by the synchronous control means,
3. The rotating machine control device according to claim 1, wherein the avoidance is performed by switching from control by the asynchronous control means to control by the synchronous control means.   4. The control device for a rotating machine according to claim 3, wherein the switching means performs at least one of torque of the rotating machine, an output current of the DC / AC converter circuit, and an input voltage as input. .   5. The rotating machine control device according to claim 3, wherein the switching unit performs the switching by inputting at least one of a frequency of an output voltage of the DC-AC converter circuit and a magnitude of the output voltage. 6. .   The said synchronous control means is a pattern waveform control means (56) which determines the switching timing of the switching state of the said switching element according to the electrical angle of the said rotary machine, The any one of Claims 3-5 characterized by the above-mentioned. The control apparatus of the rotary machine as described in 2.   The synchronization control means operates the switching element based on a magnitude comparison between a carrier wave having a period of 1 / integer of the period of the output voltage and a command voltage as an operation amount for controlling the control amount. The control device for a rotating machine according to any one of claims 3 to 5, wherein the control device is PWM processing means (40). By operating a DC / AC converter circuit (INV) including a switching element that opens and closes between each terminal of the rotating machine (10) and the positive electrode and the negative electrode of the DC voltage source (CNV), the control amount of the rotating machine Operating means (30) for controlling
The operation means includes
Asynchronous control means for switching the switching state of the switching element at random with respect to the period of the output voltage in order to manipulate the output voltage of the DC / AC converter circuit in order to control the control amount of the rotating machine;
Synchronizing to switch the switching state of the switching element in synchronization with the period of the output voltage or a period of 1 / integer thereof in order to manipulate the output voltage of the DC / AC converter circuit to control the control amount of the rotating machine Control means;
Switching means for switching from control by the asynchronous control means to control by the synchronous control means,
The control device for a rotating machine, wherein the switching means performs at least one of torque of the rotating machine, an output current of the DC / AC converter circuit, and an input voltage as input.

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