Rotating machine control device

Abstract

This rotating machine control device (1) comprises a switching command generation unit (2) for causing an electric power converter (3) to convert a DC voltage to an AC voltage and apply said voltage to a rotating machine (5), and commanding a switching operation of a PWM pulse of the electric power converter (3). The switching command generation unit (2) has a command voltage generator (7) for generating a command voltage, and a command voltage corrector (8) for correcting the command voltage generated by the command voltage generator (7). The command voltage corrector (8) corrects the command voltage on the basis of electric-current-related information pertaining to the rotating machine (5) such that the electric-current-related information does not exceed a preset threshold value.

Description

[Technical Field]

[0001] The present application relates to a rotating machine control device. [Background technology]

[0002] In rotating machine control devices, pulse width modulation (PWM) technology using the switching operation of a power converter is commonly used to apply the desired AC voltage to the rotating machine. Because switching operations incur losses, it is desirable to minimize the number of switching operations. However, reducing the number of switching operations increases voltage harmonics and current harmonics, resulting in an increase in the peak of the phase current (hereinafter referred to as peak current). Since an increase in peak current can lead to demagnetization or element damage, it is desirable to reduce both the number of switching operations and the peak current.

[0003] One method for suppressing the increase in peak current is to superimpose a sixth-order component (fifth- and seventh-order components on fixed coordinates) on the current command and control the current so that the phase current waveform becomes trapezoidal (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6455295 [Non-patent literature]

[0005] [Non-Patent Document 1] Sugimoto et al., "Theory and Design Practice of AC Servo Systems (6th Edition)," Sogo Electronics Publishing, August 2002, pp.72-98 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when the number of switching operations is reduced using the configuration of Patent Document 1, it is not possible to appropriately control harmonic currents (sixth-order components), and depending on the harmonic current and phase, it may actually increase the peak current. Also, with the configuration of Patent Document 1, even if the peak current were to exceed a predetermined value, it was not possible to instantaneously control the PWM pulse (pulse-width modulated pulse), which posed a problem in that it was unable to respond to an instantaneous increase in peak current.

[0007] For example, in applications where this rotating machine control device is used, such as factory automation (FA), air conditioning, machine tools, aircraft, railways, or automobiles, a momentary increase in peak current can cause demagnetization of power converters or element destruction.

[0008] The present application discloses a technology for solving the above-mentioned problems, and aims to reliably suppress an increase in peak current flowing through a rotating machine and protect the rotating machine and the power converter, even when the number of switching times of the power converter is reduced or when harmonic currents cannot be controlled to the desired value. [Means for solving the problem]

[0009] The rotating machine control device disclosed in the present application comprises: A rotating machine control device includes a power converter that converts a DC voltage into an AC voltage and applies the AC voltage to a rotating machine, and a current detector that detects a current flowing through the rotating machine, and controls the rotating machine, a switching command generating unit that generates a command voltage based on an operation command input from an external device and issues a switching command to the power converter based on the command voltage; The switching command generating unit generates the command voltage A PWM pulse that commands the switching operation of the power converter is a command voltage generator that generates a command voltage; generated by the command voltage generator The PWM pulse is generated by using the detected current of the current detector. a command voltage corrector for correcting the voltage; and The command voltage corrector Test Output current The peak of the current command value is one of the predetermined current command value and the current estimated value predicted or estimated from the rotating machine characteristics. Current-related information is provided in advance. Defined upper limit of current Do not exceed Whether or not to correct the PWM pulse is determined based on the value of the detected current, a first threshold value that is predetermined for the positive and negative polarities of the AC current that is the detected current, and a second threshold value that is smaller than the first threshold value. Correct the command voltage At the same time, the corrected command voltage is used as a switching command to be input to the power converter. , It is characterized by the following. [Effects of the Invention]

[0010] According to the rotating machine control device disclosed in the present application, even when the number of switching operations of the power converter is reduced or when the harmonic current cannot be controlled to a desired value, The PWM pulse that commands the switching operation of the power converter can be controlled instantaneously. This reliably suppresses increases in peak current flowing through the rotating machine, thereby protecting the rotating machine and the power converter. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic diagram illustrating an example of a rotating machine control device according to a first embodiment. [Figure 2] 2 is a block diagram illustrating the internal configuration of a switching command generating unit of the rotating machine control device according to the first embodiment. FIG. [Figure 3] 2 is a block diagram illustrating the internal configuration of a command voltage corrector of the rotating machine control device according to the first embodiment. FIG. [Figure 4] 2 is a block diagram illustrating the internal configuration of a hysteresis comparator of the rotating machine control device according to the first embodiment. FIG. [Figure 5] 3 is a block diagram illustrating the internal configuration of an allowable range setter of the rotating machine control device according to the first embodiment. FIG. [Figure 6] 4 is a diagram showing an example of operation of the rotating machine control device according to the first embodiment when no correction of a command voltage is performed. FIG. [Figure 7] 4 is a diagram showing an example of operation when a command voltage of the rotating machine control device according to the first embodiment is corrected. FIG. [Figure 8] 4 is a diagram showing an example of operation of the rotating machine control device according to the first embodiment when no correction of a command voltage is performed. FIG. [Figure 9]4 is a diagram showing an example of operation when a command voltage of the rotating machine control device according to the first embodiment is corrected. FIG. [Figure 10] 5 is a diagram showing an example of operation when the value of the allowable range is changed after correcting the command voltage of the rotating machine control device according to the first embodiment. FIG. [Figure 11] 2 is a hardware configuration diagram of a switching command generation unit of the rotating machine control device according to the first embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Embodiment 1 The rotating machine control device according to the first embodiment of the present invention will be described in detail below with reference to the drawings. 1 is a schematic diagram of a rotating machine control device according to embodiment 1. The rotating machine control device 1 is composed of a switching command generation unit 2, a power converter 3 that receives a DC voltage from a DC power supply 4 and applies a power conversion AC voltage to a rotating machine 5, and a current detector 6 that detects the AC current output from the power converter 3.

[0013] The switching command generator 2 generates a pulsed command voltage (hereinafter also referred to as a voltage command) based on an AC current and operation commands such as a command torque, a command rotational speed, and a current command, and issues a switching command to the power converter 3. The power converter 3 includes a switching element 31 configured, for example, as a full-bridge circuit. The power converter 3 is connected to a DC power supply 4 and a rotating machine 5 via wiring. The power converter 3 generates an AC voltage from the DC power supply 4 based on the switching command from the switching command generator 2, and applies the AC voltage to the rotating machine 5. Naturally, when the rotational speed approaches 0, the AC current and AC voltage become DC current and DC voltage, and when an offset component is included, the AC current and AC voltage contain not only an AC component but also a DC component. The current detector 6 detects the currents iu, iv, and iw of each phase (U phase, V phase, W phase) of the rotating machine 5.

[0014] The current detector 6 may be substituted with a predetermined current command value for some or all of the phases. Alternatively, a current estimated value estimated by a current estimator that predicts or estimates the current from the rotating machine characteristics as shown in equation (1) may be substituted. Furthermore, a configuration that detects the current on the DC bus side and calculates the current for each phase may be used as a substitute. A current estimator may be used as a substitute for a current sensor to reduce costs, but when used in place of a current sensor with low accuracy or response, it can reliably observe transiently changing currents. This makes it possible to reliably protect the rotating machine or the power converter even when there is no current sensor or when the response of the current sensor is slow.

[0015]

number

[0016] Here, equation (1) is the voltage equation on the fixed coordinates (uvw coordinates) of the rotating machine, where Vu, Vv, and Vw are the phase voltages, R is the winding resistance, s is the differential operator, Lu, Lv, and Lw are the self-inductances of each winding, Muv, Mwu, Mvw is the mutual inductance between each winding, iu, iv, iw are the phase currents, ω re is the electrical angular velocity, φ mag is the permanent magnet magnetic flux, θ re represent the electrical angle position, respectively.

[0017] The rotating machine 5 is assumed to be a three-phase synchronous motor or a three-phase induction motor, but it may also be a motor other than three phases, such as a dual three-phase winding motor or a five-phase motor, for example, a field winding motor, or a synchronous reluctance motor, switched reluctance motor, or other motor other than an induction motor.

[0018] Next, a description will be given of Fig. 2. Fig. 2 is a block diagram illustrating the internal configuration of the switching command generation unit 2 according to embodiment 1. The switching command generation unit 2 is made up of a command voltage generator 7 and a command voltage corrector 8.

[0019] The command voltage generator 7 generates an AC voltage command based on the operation command and the AC current by a known method (see Non-Patent Document 1). The AC voltage command is realized by converting the operation command into a current command and controlling a current vector on the rotating coordinate system (d-q coordinate system) so that the AC current follows the current command, or it may be configured to obtain a three-phase voltage command according to the command rotation speed, as in V / f constant control.

[0020] Furthermore, although not shown, when current vector control is performed, rotor position information is acquired using a position sensor such as a resolver or an encoder, or a position estimator that serves as a substitute for a position sensor, and an AC voltage command is generated.

[0021] After generating the AC voltage command, a PWM pulse is generated to command the switching operation of the power converter 3. The PWM pulse is generated so that at least the fundamental wave component of the PWM pulse matches the fundamental wave component of the AC voltage command, and is generally calculated by comparing a triangular wave carrier with the AC voltage command.

[0022] The triangular wave carrier is composed of a synchronous carrier (synchronous PWM) synchronized with the voltage phase or rotation speed, or an asynchronous carrier (asynchronous PWM) that is not synchronized with the voltage phase or rotation speed.In addition to comparison with the triangular wave carrier, the PWM pulse may also be calculated using direct torque control, optimal pulse pattern method, low-order harmonic elimination method, space vector modulation method, hysteresis comparator method, etc.

[0023] However, even if the PWM pulses are calculated using any of the above methods, the greater the number of PWM pulses per electrical angle cycle, the more the voltage harmonics and current harmonics tend to decrease, and the fewer the number of PWM pulses, the more the voltage harmonics and current harmonics tend to increase. When voltage harmonics and current harmonics increase, the peak current also increases. If the peak current exceeds the upper current limit, it may cause demagnetization or element destruction, so the peak current flowing through the rotating machine must be controlled so as not to exceed the upper current limit.

[0024] On the other hand, when it comes to switching loss, the more PWM pulses there are per electrical cycle, the greater the switching loss, and the fewer the number of PWM pulses, the lower the switching loss.Increased switching loss leads to heat generation and reduced efficiency.

[0025] As described above, there is a trade-off between voltage harmonics, current harmonics, and switching loss, so it is generally desirable to reduce the number of switching operations so that the peak current does not exceed the current upper limit.

[0026] The command voltage corrector 8 corrects the PWM pulses based on the PWM pulses generated by the command voltage generator 7 and the current detected by the current detector 6 , and generates a switching command to be input to the power converter 3 .

[0027] 3 is a block diagram illustrating the internal configuration of the command voltage corrector 8 in the rotating machine control device of embodiment 1. The command voltage corrector 8 is configured with a switching frequency calculator 9, a hysteresis comparator 10, a tolerance range setter 11, a correction determiner 12, and a correction processor 13.

[0028] The switching number calculator 9 calculates the number of switching times based on the switching command generated by the correction processor 13 and outputs the number of switching times to the allowable range setter 11 . The hysteresis comparator 10 determines whether or not the PWM pulse generated by the command voltage generator 7 should be corrected based on the value of the detected current detected by the current detector 6 and the inversion and non-inversion thresholds output from the tolerance range setter 11, and outputs a correction flag.

[0029] Specifically, as shown in Fig. 4, an inversion threshold and a non-inversion threshold are set for the positive and negative polarities of the AC current, and when the amplitude of the AC current becomes larger than the inversion threshold (also referred to as the first threshold), a correction flag is output to invert the PWM pulse (positive and negative polarity) generated by the command voltage generator 7 (hereinafter referred to as inversion processing). The correction flag continues the operation of inverting the PWM pulse, and when the amplitude of the AC current becomes smaller than the non-inversion threshold (also referred to as the second threshold), the PWM pulse is not inverted (non-inversion), that is, a correction flag is output so that the PWM pulse generated by the command voltage generator 7 is output as is (hereinafter referred to as non-inversion processing).

[0030] This takes advantage of the characteristic that the phase current changes in the direction of the polarity of the PWM pulse (when the PWM pulse is high, the phase current increases in the positive direction; when the PWM pulse is low, the phase current increases in the negative direction), and when it is predicted or estimated that the peak current will exceed the current upper limit, the PWM pulse is reversed to reduce the peak current.

[0031] With this configuration, even if the peak current is about to exceed a predetermined value, the PWM pulse can be instantaneously manipulated, so that the peak current can be reliably controlled so as not to exceed the upper current limit. Also, by correcting the PWM pulse as in this configuration, it is possible to suppress only the increase in the transiently changing peak current, with almost no effect on the fundamental wave component of the command voltage generated by the command voltage generator 7 (there is no need to change the command to reduce the output).

[0032] Here, we have taken the example of a case where the peak of the detected current exceeds a threshold value, but the target may also be other things besides the peak of the detected current, such as voltage or current including harmonics, loss, power, torque, rotation speed, rotor position, or temperature (for example, the amplitude of a specific harmonic voltage or current, or the sum of these amplitudes).

[0033] As described above, the rotating machine control device of this embodiment 1 can control the switching command to correct so that the peak of the current flowing through the rotating machine does not exceed a predetermined threshold, thereby reliably protecting the rotating machine or power converter.

[0034] The tolerance range setter 11 determines the inversion and non-inversion thresholds based on the switching count of the switching count calculator 9 and the upper limit of the correction count, which is the number of times the switching command is corrected, and outputs the determined values ​​to the hysteresis comparator 10. Here, the tolerance range refers to the difference between the non-inversion threshold and the inversion threshold. The inversion threshold is set to a value that ensures that the peak current does not exceed the upper current limit during the period from current detection to voltage output. The non-inversion threshold is set to a value that ensures that the PWM pulse corrected during the inversion process does not deviate too much from the PWM pulse generated by the command voltage generator 7, and that does not increase the number of inversion processes too much, thereby causing the number of switching operations to become too large.

[0035] Specifically, if the difference (tolerance) between the inversion threshold and the non-inversion threshold is made too large, a voltage command that is significantly different from the PWM pulse generated by the command voltage generator 7 will be generated, resulting in unstable control. On the other hand, if the tolerance is made too small, inversion and non-inversion will be repeated more than necessary, resulting in an unnecessarily large increase in switching loss.

[0036] Therefore, as shown in Figure 5, the inverted and non-inverted thresholds are set in advance to ensure that the peak current does not exceed the upper current limit and does not deviate too far from the PWM pulse generated by the command voltage generator 7. Only when the number of switching operations becomes greater than necessary are the inverted and non-inverted thresholds changed and set to a larger tolerance. Increasing the tolerance makes it more difficult to reach the inverted or non-inverted threshold, thereby reducing the number of corrections.

[0037] Here, an example has been given in which the inversion threshold and non-inversion threshold are changed according to the number of switching operations, but it is also possible to change the values ​​according to one or more of the following conditions: rotation speed, current, voltage, torque, rotor position, rotating machine temperature, and power converter temperature, in addition to the number of switching operations. This makes it possible to reliably and appropriately protect the rotating machine and power converter under any circumstances (especially when the influence of heat is large).

[0038] By manipulating the tolerance range, the following operation is also possible. If the tolerance range is deliberately set larger than necessary, the modulation factor command of the AC voltage command generated by the command voltage generator 7 can be increased. In this case, if the amplitude of the AC voltage command can be made larger than the triangular wave carrier when generating PWM pulses, overmodulation drive can be achieved and the number of switching times can be reduced.

[0039] Overmodulation driving is a technology generally used to increase the utilization rate of power converter output, but in this configuration, overmodulation driving can be used to reduce the number of switching operations. Naturally, even when overmodulation driving is in use, the hysteresis comparator 10 controls the phase current near its peak so that it does not reach the current upper limit, so the advantage of not increasing the peak current more than necessary can be maintained.

[0040] The correction determiner 12 determines whether to correct the PWM pulse based on the correction flag and the upper correction count limit value of the hysteresis comparator 10, and outputs a correction pulse. The upper correction count limit value defines an upper limit on the number of corrections during control cycle 1, preventing a significant increase in the number of switching operations. If the number of corrections based on the correction flag during control cycle 1 does not reach the upper correction count limit value, a correction pulse is output to allow correction. If the number of corrections based on the correction flag exceeds the upper limit, the peak current may exceed the current upper limit or the number of switching operations may increase too much. Therefore, operation is stopped or the tolerance range of the tolerance range setter 11 is changed to an appropriate value. In this way, the rotating machine control device of this embodiment 1 is capable of detecting an abnormal state.

[0041] The correction processor 13 generates a switching command using the PWM pulse generated by the command voltage generator 7 and the correction pulse generated by the correction determiner 12 , and outputs the command to the power converter 3 . As described above, by providing a hysteresis characteristic for whether or not to correct the switching command, it is possible to prevent the number of switching corrections from increasing too much.

[0042] Next, the effects of the rotating machine control device 1 will be described. Fig. 6 is a diagram showing an enlarged view of an AC current waveform generated by a conventional PWM pulse that does not have a command voltage compensator 8. Fig. 6A shows the current characteristics, and Fig. 6B shows the voltage characteristics (the same applies to Figs. 7A to 10A and 7B to 10B described below). In Fig. 6B, the switching command characteristics are shown by a solid line, the modulation signal characteristics by a dotted line, and the triangular wave carrier characteristics by a dashed line (the same applies to Figs. 7B to 10B described below). In particular, when the number of switching operations is small as shown in FIG. 6B, the peak current of the AC current waveform exceeds the upper limit of the current (see the circle surrounded by the dotted line in FIG. 6A).

[0043] 7A and 7B are diagrams showing enlarged views of the AC current waveform when the PWM pulse is corrected using the command voltage corrector 8. In this case, the peak of the AC current does not reach the upper limit of the current, but it increases toward this upper limit, and if this increase continues, it will exceed the inversion threshold, which is a value smaller than the upper limit of the current (see FIG. 7A).

[0044] When the inversion threshold is exceeded, the PWM pulse is corrected by the command voltage corrector 8 and the switching command is inverted (see FIG. 7B), so the peak current does not reach the current upper limit (see FIG. 7A). Furthermore, when the AC current becomes smaller than the non-inversion threshold during the inversion process, the inversion process is canceled and the PWM pulse generated by the command voltage generator 7 is output, enabling stable control operation. That is, since the pulse waveform (switching signal) is directly controlled, peak current can be protected more reliably.

[0045] Figures 8A and 8B show the operation when the number of switching operations is increased. Figure 8A, like Figure 6A, and Figure 8B, like Figure 6B, show the AC current waveform results using a conventional PWM pulse. Figure 9A, like Figure 7A, and Figure 9B, like Figure 7B, show the results when the PWM pulse is corrected by command voltage corrector 8 and the peak current is controlled so as not to reach the current upper limit.

[0046] As shown in Figure 9A, the peak current is controlled so that it does not reach the upper limit, but as mentioned above, there is a concern that correcting the PWM pulse may increase the number of switching operations too much. In such cases, by setting the tolerance wider than in the cases shown in Figures 9A and 9B, overmodulation drive can be achieved, and it is possible to prevent the peak current from reaching the current upper limit while also reducing the number of switching operations (see Figures 10A and 10B). In other words, it is possible to prevent an increase in the number of switching operations due to the command voltage corrector.

[0047] In this application, it is stated that the PWM pulse is corrected so that the current flowing through the rotating machine does not exceed the upper current limit value, so basically, control is performed so that the current or current-related information such as the current command value or current estimated value does not exceed a threshold value, but the same effect can be obtained even when the current unintentionally exceeds the threshold value (due to the occurrence of a sampling error, a sensor error, etc.). Therefore, the scope of application of this application is not limited to cases where the current or current-related information does not exceed the threshold value.

[0048] Although the above description describes a direct correction of the PWM pulse so that the current flowing through the rotating machine does not exceed the upper current limit, the PWM pulse may be indirectly corrected by correcting the amplitude or phase of the command voltage that generates the PWM pulse. Specifically, when the current flowing through the rotating machine exceeds a first threshold, the amplitude or phase of the command voltage is corrected so that the polarity of the PWM pulse is reversed. When the current flowing through the rotating machine falls below a second threshold, the amount of correction of the amplitude or phase of the command voltage is reduced so that the polarity of the PWM pulse is not reversed. Alternatively, a similar effect can be achieved by a configuration in which the amplitude or phase of a triangular wave carrier used to generate a PWM pulse instead of a command voltage is similarly corrected, thereby indirectly correcting the PWM pulse.

[0049] 11 shows an example of hardware of the switching command generation unit 2 of the rotating machine control device 1 of the present application. It is composed of a processor 100 and a storage device 101. Although not shown, the storage device 101 includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory. Furthermore, an auxiliary storage device such as a hard disk may be included instead of the flash memory.

[0050] Furthermore, although exemplary embodiments are described herein, the various features, aspects, and functions described in the embodiments are not limited to application to a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed in the present specification, including, for example, modifying, adding, or omitting at least one component. [Explanation of symbols]

[0051] 1 Rotating machine control device, 2 Switching command generation unit, 3 Power converter, 4 DC power supply, 5 Rotating machine, 6 Current detector, 7 Command voltage generator, 8 Command voltage corrector, 9 Switching frequency calculator, 10 Hysteresis comparator, 11 Tolerance width setter, 12 Correction determiner, 13 Correction processor, 31 Switching element, 100 Processor, 101 Storage device

Claims

1. A rotating machine control device includes a power converter that converts a DC voltage into an AC voltage and applies the AC voltage to a rotating machine, and a current detector that detects a current flowing through the rotating machine, and controls the rotating machine, a switching command generating unit that generates a command voltage based on an operation command input from an external device and issues a switching command to the power converter based on the command voltage; The switching command generation unit includes a command voltage generator that generates a PWM pulse that commands a switching operation of the power converter, the command voltage being the command voltage; a command voltage corrector that corrects the PWM pulse generated by the command voltage generator using the current detected by the current detector; and the command voltage corrector determines whether to correct the PWM pulse based on the value of the detected current, a first threshold value that is predetermined for positive and negative polarities of the AC current that is the detected current, and a second threshold value that is smaller in magnitude than the first threshold value, so that current-related information that is any one of a peak of the detected current, a predetermined current command value, and a current estimated value predicted or estimated from rotating machine characteristics does not exceed a predetermined current upper limit value, and corrects the command voltage, and uses the corrected command voltage as a switching command to be input to the power converter. A rotating machine control device characterized by:

2. The command voltage corrector is When the current flowing through the rotating machine exceeds the first threshold, the amplitude or phase of the command voltage is corrected, and when the current flowing through the rotating machine becomes smaller than the second threshold, the amount of correction of the amplitude or phase of the command voltage is reduced. The rotating machine control device according to claim 1 .

3. The command voltage corrector is When the amplitude of the AC current becomes larger than the first threshold value, the polarity of the PWM pulse generated by the command voltage generator is inverted, and when the amplitude of the AC current becomes smaller than the second threshold value as a result of the above operation, the polarity of the PWM pulse generated by the command voltage generator is not inverted and the PWM pulse is output as is. The rotating machine control device according to claim 1 .

4. the command voltage corrector has a switching number calculator that calculates the number of switching times, changing the first threshold value and the second threshold value so that the difference between the first threshold value and the second threshold value becomes large when the number of switching times is greater than a preset threshold value; The rotating machine control device according to any one of claims 1 to 3.

5. the first threshold is a reversal threshold set for positive and negative AC current, and the second threshold is a non-reversal threshold set for positive and negative AC current, and the reversal threshold and the non-reversal threshold are changed in value depending on the number of switching times or the current state; 5. The rotating machine control device according to claim 4.

6. the command voltage corrector has a correction determiner that determines whether or not the command voltage should be corrected; the correction determiner determines whether or not to correct the PWM pulse based on a correction flag output from a hysteresis comparator that determines whether or not to correct the PWM pulse based on the value of the detected current detected by the current detector, an inversion threshold value and a non-inversion threshold value output from a tolerance range setter that sets a tolerance range that is the difference between the first threshold value and the second threshold value, and based on a preset upper limit value for the number of corrections, outputs a correction pulse; and calculates the number of times to correct the command voltage between preset control periods, and stops outputting the correction determiner when the number of times to correct the command voltage exceeds the preset upper limit value for the number of corrections. The rotating machine control device according to any one of claims 1 to 3.

7. the command voltage corrector has a correction determiner that determines whether or not the command voltage should be corrected; the correction determiner determines whether or not to correct the PWM pulse based on a correction flag output of a hysteresis comparator that determines whether or not to correct the PWM pulse based on the value of the detected current detected by the current detector and an inversion threshold value and a non-inversion threshold value output from an allowance range setter that sets an allowance range that is the difference between the first threshold value and the second threshold value, and based on a preset upper limit value of the number of corrections, and outputs a correction pulse; calculating the number of times to correct the command voltage during a preset control cycle, and stopping the output of the correction determiner when the number of times to correct the command voltage exceeds a preset upper limit value of the number of corrections; 5. The rotating machine control device according to claim 4.

8. the command voltage corrector has a correction determiner that determines whether or not the command voltage should be corrected; the correction determiner determines whether or not to correct the PWM pulse based on a correction flag output of a hysteresis comparator that determines whether or not to correct the PWM pulse based on the value of the detected current detected by the current detector and an inversion threshold value and a non-inversion threshold value output from an allowance range setter that sets an allowance range that is the difference between the first threshold value and the second threshold value, and based on a preset upper limit value of the number of corrections, and outputs a correction pulse; calculating the number of times to correct the command voltage during a preset control cycle, and stopping the output of the correction determiner when the number of times to correct the command voltage exceeds a preset upper limit value of the number of corrections; The rotating machine control device according to claim 5 .

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