JP2009232606A - Device and method for controlling power converter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simultaneously reduce EMI noises caused by switching a power converter in a plurality of desired frequency bands. <P>SOLUTION: A frequency group memory part 91 stores a plurality of frequency groups, each of which is a collection of carrier frequencies of which harmonics do not enter the desired frequency bands. The desired frequency band of each frequency group is different one from each other. In a frequency group switching part 99, the plurality of frequency groups stored in the frequency group memory part 91 are switched for each determined time and output to a carrier signal generation part 8. The carrier signal generation part 8 outputs carrier signals based on the frequency groups. A current control part 10 calculates a current instruction value from a current instruction generating part 5 and a current detection value from a current detection part 4 and outputs a voltage instruction. In a switching signal generation part 7, PWM comparison between a voltage instruction value and the carrier signal is made, and an on/off signal to the switching element of the power converter 2 is output. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a power conversion device that drives a load device with PWM (Pulse Width Modulation), and more particularly, to a control device and a control method for a power conversion device with a variable carrier frequency for PWM driving.

The PWM-driven power conversion device generates electromagnetic interference (EMI) noise in the harmonic frequency band of the switching frequency (carrier frequency) in order to drive the load device with a PWM pulse train. In order to reduce the influence of this EMI noise, a power conversion device is known in which the carrier frequency is changed over time so as to repeat each of the two frequency ranges (for example, Patent Document 1). As a result, the EMI noise is reduced over a wide band, and the levels of some specific frequency bands are further reduced.
JP 2006-136138 A

  However, in the power conversion device of the patent document, when trying to simultaneously reduce EMI noise in a plurality of specific frequency bands, for example, the specific frequency band A and the specific frequency band B, when the specific frequency band A is reduced, When the EMI noise of the specific frequency band B cannot be reduced and the EMI noise of the specific frequency band B is reduced, there is a problem that the EMI noise of the specific frequency band A cannot be reduced. It was.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a control device and a control method for a power converter that can simultaneously reduce EMI noises in a plurality of specific frequency bands.

  In order to solve the above problems, the present invention provides a control device for a power converter that drives a load device by PWM control, and a carrier selected based on a desired frequency band in which interference from harmonics of the carrier frequency is desired to be suppressed. The gist is that a plurality of frequency groups, which are a set of frequency values, are stored in the frequency group storage means, and the frequency groups are switched at a predetermined time t by the frequency group switching means to be carrier frequencies.

  According to the present invention, there is an effect that the EMI noise level can be simultaneously reduced in a plurality of desired frequency bands.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. Although not particularly limited, each embodiment described below is a preferred embodiment for a control device of a power conversion device that can effectively reduce EMI for in-vehicle devices.

  FIG. 1 is a system configuration diagram illustrating a configuration example of a power control system 1 including a first embodiment of a control device for a power conversion device according to the present invention. As shown in FIG. 1, the power control system 1 includes a power converter 2 that is an inverter that converts DC power supplied from a DC power source (not shown) into AC by PWM control, and AC power converted by the power converter 2. A load device 3 that is an AC motor driven by the motor, a current detection unit 4 that detects a current of each phase of the load device 3, a current command generation unit 5, and a control device 6 that controls the power conversion device 2. ing.

  The control device 6 includes a switching signal generation unit 7, a carrier signal generation unit 8, a carrier frequency variable unit 9, and a current control unit 10.

  The control device 6 calculates a current command value from the current command generation unit 5 and a current detection value from the current detection unit 4 by the current control unit 10, and outputs a voltage command from the current control unit 10. When the voltage command from the current control unit 10 is input to the switching signal generation unit 7, the switching signal generation unit 7 performs PWM comparison and outputs an on / off signal to the switching element of the power conversion device 2.

  The carrier frequency variable unit 9 changes the frequency (carrier frequency) of the carrier signal output from the carrier signal generation unit 8. In accordance with the on / off signal indicating the PWM pattern output from the switching signal generation unit 7, the switching device inside the power conversion device 2 is turned on / off to supply the PWM device to the load device 3.

  The carrier frequency variable unit 9 includes a frequency group storage unit 91 and a frequency group switching unit 99. The frequency group storage unit 91 stores a plurality of frequency groups such as a frequency group A92, a frequency group B93, a frequency group C94,. Here, the frequency group A92 is a set of carrier frequencies in which the harmonics of the carrier frequencies included in the frequency group A92 do not become the first frequency band. The frequency group B93 is a set of carrier frequencies in which the harmonics of the carrier frequencies included in the frequency group B93 do not become the second frequency band. Similarly, the frequency group n is a set of carrier frequencies in which the harmonics of the carrier frequencies included in the frequency group n are not in the nth frequency band.

  The frequency group switching unit 99 switches the plurality of frequency groups A92, frequency groups B93, frequency groups C94,... Stored in the frequency group storage unit 91 at predetermined time intervals and outputs them to the carrier signal generation unit 8. The carrier signal generation unit 8 changes the frequency of the carrier signal by the output of the frequency group switching unit 99. As a result, the EMI level from the carrier frequency in a plurality of desired frequency bands can be suppressed.

  FIG. 2 is a diagram illustrating a configuration example of the current control unit 10 in FIG. As shown in FIG. 2, the current control unit 10 is calculated by the calculation unit 101 that calculates the deviation between the current command value from the current command generation unit 5 and the current value detected by the current detection unit 4. A proportional-integral control unit 102 that outputs a voltage command value by performing proportional-integral control (PI control) on the obtained value is provided as a constituent element. In FIG. 2, the proportional control is described as an example of the current control unit 10, but this is not a limitation. Proportional control (P control) or proportional integral derivative control (PID control) may be used. Here, the current value detected by the current detection unit 4 is, for example, current values of U phase, V phase, and W phase supplied from the power conversion device 2 (inverter) to the load device 3 (AC motor). The three-phase / two-phase signals detected by the unit 4 and converted from the three-phase quantities (U-phase, V-phase, W-phase) to the currents of the d-axis coordinates and q-axis coordinates, which are two-phase quantities, via the coordinate converter 41. Indicates the coordinate transformed one.

  FIG. 3 is a diagram illustrating a configuration example of the switching signal generation unit 7 in FIG. As shown in FIG. 3, the switching signal generation unit 7 is generated by a coordinate conversion unit 71 that performs coordinate conversion of the voltage command value output from the current control unit 10, and the carrier signal generation unit 8 that generates the coordinate-converted value. Comparator 72a, 72b, 72c for comparing the magnitude relationship with the value of the carrier signal, and signal inverters (inverters) 73a, 73b, 73c for inverting the output signals of the comparators 72a, 72b, 72c, respectively. As prepared.

  The coordinate conversion unit 71 performs two-phase / three-phase coordinate conversion to convert the voltage command value supplied from the current control unit 10 from the d-axis coordinate and q-axis coordinate values to the U-phase, V-phase, and W-phase values. Is going. The voltage command value subjected to coordinate conversion and the triangular wave carrier signal from the carrier signal generator 8 are compared by the comparators 72a, 72b, 72c, and the ON / OFF signal of the power converter 2 is determined according to the magnitude relationship. Tu +, Tv +, and Tw + are output. The signal inverters 73a, 73b, and 73c output Tu−, Tv−, and Tw− obtained by inverting Tu +, Tv +, and Tw +, respectively, as on / off signals to the power converter 2.

  Next, the time change of the carrier frequency (fc) will be described with reference to FIG. In this embodiment, the carrier frequency is controlled by a CPU such as a microcomputer. Therefore, when the carrier frequency is changed in the present embodiment, the carrier frequency does not change continuously but changes with discrete values. For example, when the carrier frequency is changed to a triangular wave shape, the carrier frequency is a change in which steps of small steps continue as shown in FIG. That is, the upward staircase continues from the minimum value to the maximum value of the carrier frequency, and when the maximum value is reached, the downward staircase continues toward the minimum value. When it reaches the minimum value, it repeats so that the upstairs will continue again.

  The value of the carrier period is an integral multiple of Δt, where Δt is the CPU clock period. The carrier frequency is the reciprocal. It is assumed that the range that can be used as the carrier frequency is given as fcmin or more and fcmax or less from system requirements (for example, suppression of heat generation of switching elements of the inverter, suppression of generation of acoustic noise, etc.). If the clock period of the CPU is Δt, the carrier frequency value that can be used to change the carrier frequency is a reciprocal of an integral multiple of Δt and a value that is greater than or equal to fcmin and less than or equal to fcmax.

  FIG. 5 shows a waveform example of the carrier signal in the switching signal generator 7. As shown in FIG. 5, the carrier signal has a triangular wave shape, and when the frequency of the carrier signal (carrier frequency) is constant, the interval between the peaks of the triangular wave is constant (broken line). A solid line shows the carrier frequency changed with time. As shown in the figure, when the carrier frequency is changed with time, the frequency changes as the peak of the carrier signal changes.

  FIG. 6 is a principal circuit diagram illustrating a configuration example of the power conversion device 2 in FIG. 1. As shown in FIG. 6, the power conversion device 2 includes a DC power source 21 such as a battery, a capacitor 22, a switching circuit 23 including six switching elements, and a current detection unit 4 as components. Each switching element constituting the switching circuit 23 is configured by a semiconductor element such as an IGBT (Insulated Gate Bipolar Transistor) or a MOS-FET.

  The current detection unit 4 detects U-phase, V-phase, and W-phase current values supplied from the power conversion device 2 (inverter) to the load device 3 (motor), respectively. The switching circuit 23 is connected to the positive electrode of the DC power source composed of the DC power source 21 and the capacitor 22 in accordance with the on / off signals output from the comparators 72a, 72b, 72c and the signal inverters 73a, 73b, 73c of the switching signal generator 7. The negative electrode is selected, the selected electrode and the U-phase, V-phase, and W-phase electrodes of the load device 3 (motor) are electrically conducted, and AC power is supplied to the load device 3 (motor).

  Next, frequency groups in the carrier frequency variable unit 9 will be described with reference to FIG. FIG. 7A shows a method of selecting the carrier frequency (fc) that is each element of the frequency group. FIG. 7B is an example of a frequency group map stored in the frequency group storage unit 91. As shown in FIG. 7A, the carrier frequency fc used in the present invention has a frequency value that is an integral multiple of the carrier frequency fc, that is, a frequency corresponding to a harmonic of each fc is in a desired frequency band (fch). Select a value of fc that does not enter. By selecting such fc, the level of the EMI spectrum in a desired frequency band (fch) can be locally reduced.

  FIG. 7B shows a frequency group that is a set of carrier frequency values that do not require a harmonic that is an integral multiple of the carrier frequency in the desired band described in FIG. 7A. The counter on the vertical axis is the number of carrier frequency values included in each frequency group. Each frequency group (frequency group A, frequency group B,..., Frequency group n) shown on the horizontal axis has carrier frequency harmonics in a desired frequency band as described with reference to FIG. Each value of the carrier frequency is not present. In the notation fc (m, n), m is the order of carrier frequency values, and n is a frequency group. For example, fc (1, 5) indicates the fifth carrier frequency value in the frequency group A.

  A feature of the present invention is that a plurality of local EMI reduction bands can be created at the same time even under limited carrier frequency conditions (the above-described fcmin to fcmax is several kHz to several tens kHz in a motor / inverter). . For example, if a carrier frequency is selected from the beginning so that harmonics that are an integral multiple of the carrier frequency do not enter the desired frequency band 1 and the desired frequency band 2, a plurality of local reduction bands can be formed simultaneously. However, this means that, for example, fc (1,1) and fc (2,2) must be the same value in FIG. 7B. [(Carrier frequency not entering band 1) and (carrier frequency not entering band 2]] must be selected. On the other hand, in the present invention, since there is no correlation between frequency groups, it is only necessary to select a carrier frequency for each band. That is, for example, fc (1,1) and fc (2,2) are not related to the same value or different values.

  Next, the number of carrier frequency values (maximum counter number m in FIG. 7B) which is each element of frequency group A92, frequency group B93, frequency group C94,... Will be described. The EMI spectrum formed when the carrier frequency is changed with a discrete value with time, when the carrier frequency is operated under the condition of constant carrier frequency using the discrete value of the carrier frequency used at that time. It almost coincides with the averaged value of each EMI spectrum formed in (1). The EMI spectrum when the carrier frequency is constant is a spectrum that shows a peak at a frequency that is an integral multiple of the carrier frequency.

  In view of this, when the number of carrier frequency values used when the carrier frequency is changed with time is small, the noise spectrum shows a large uneven shape. Further, the total energy of the EMI spectrum when the carrier frequency is changed with time is considered to be the same as when the carrier frequency is constant. This can be understood from the fact that the time average of the number of times of switching, which is the cause of EMI noise, is the same. Therefore, the smaller the number of carrier frequency values used when the carrier frequency is changed with time, the greater the unevenness in the EMI noise spectrum and the higher the peak level of the EMI spectrum. Because it is desired not only to reduce the level of the EMI spectrum locally (does not add harmonics of an integral multiple of the carrier frequency in the desired band), but also to reduce the level in a wide band in other bands. In order to reduce the level other than the desired band, it is desired to flatten the spectrum. For this purpose, the number of values used as the carrier frequency when changing the carrier frequency is required to some extent.

  Note that there is no correlation between carrier frequency values in each frequency group. That is, the carrier frequency value of the frequency group A92 is a set of carrier frequency values that do not include a harmonic that is an integral multiple of the carrier frequency in the desired band 1 (fch1). The carrier frequency value of the frequency group B93 is a set of carrier frequency values such that harmonics that are integral multiples of the carrier frequency do not enter the desired band 2 (fch2).

  Here, a desired frequency band will be described. The object of the present invention is to “reduce the noise level in the frequency band where EMI noise caused by the carrier frequency becomes an obstacle”. For example, a desired frequency band will be described taking radio broadcasting as an example. The carrier wave of AM broadcasting in Japan is in the range of 531 kHz to 1602 kHz, and the channel frequency of the broadcast wave of each station is a multiple of 9 kHz. The range of ± 6 kHz of the channel frequency is the channel frequency band. That is, 12 kHz is one broadcast wave band. Nippon Broadcasting, which can be received in the Kanto region, uses 1242 kHz as a receiving channel, and the band including sidebands is 1236 kHz to 1248 kHz.

  Here, let us consider the influence of harmonics of integer multiples of the PWM carrier frequency on radio listening. For example, when the carrier frequency is 20 kHz, the frequency of the 62nd harmonic is 1240 kHz. Since this enters the band of the Nippon Broadcasting Channel, noise may be mixed into the audio output, which may affect the listening. In this case, the desired frequency band is 1236 kHz to 1248 kHz. In this way, a desired frequency band is determined. A desired bandwidth (12 kHz in the above example) may be set to the lowest frequency used in each frequency group.

  Next, the operation of the frequency group switching unit 99 in the carrier frequency variable unit 9 will be described with reference to FIG. In the present embodiment, the frequency group stored in the frequency group storage unit 91 is switched by the frequency group switching unit 99 every predetermined time and output to the carrier signal generation unit 8, so that a plurality of desired frequency bands (fch) are obtained. The level of the EMI spectrum can be locally reduced. Here, a method of locally reducing the level of the EMI spectrum of two desired frequency bands using the two frequency groups A92 and B93 from the frequency group storage unit 91 will be described.

  FIG. 8A shows changes in the carrier frequency (fc) of the frequency group A92 and the frequency group B93. When the carrier frequency is changed to a triangular wave as described with reference to FIG. 4, the modulation periods of the frequency group A92 and the frequency group B93 are the reciprocals (1 / fc) of the carrier frequency values used in the respective frequency groups. The total is t1 [ms] and t2 [ms].

  FIG. 8B is an explanatory diagram when the frequency group switching unit 99 switches the frequency group every predetermined time and outputs it to the carrier signal generation unit 8. As shown in FIG. 8 (b), the frequency group switching unit 99 repeats the frequency group A and the frequency group B N times each, thereby totaling the modulation periods of the frequency group A and the frequency group B (t1 × N , T2 × N) is adjusted to be 10 [ms] or more and 200 [ms] or less, which is a predetermined time. For example, the modulation period t1 of the frequency group A is 1 ms, and the modulation period t2 of the frequency group B is 1.2 ms. When each frequency group is repeated 15 times, the sum of the modulation periods becomes 15 ms and 18 ms. Here, the number of repetitions N is the same for the frequency group A and the frequency group B, but is not limited to this, and the frequency group A may be N times and the frequency group B may be M times. However, each frequency group is adjusted so that the sum of the modulation periods is 10 ms to 200 ms.

  Next, with reference to FIG. 9, the selection of the predetermined time for switching the frequency group in the frequency group switching unit 99 and the effect of the present embodiment will be described. FIG. 9A shows the noise level measured with the sound level meter in the desired band 1 and FIG. 9B shows the desired band 2 when receiving the AM broadcast in this embodiment. The vertical axis is the sound pressure level measured by a sound level meter (which measures the sound pressure level according to the characteristics of the human ear). The larger the sound pressure level, the greater the noise level (in this case, the effect on radio listening) Is great). The horizontal axis represents the frequency group switching time.

  Note that since FIG. 9 is evaluated based on the sound pressure level, both of the desired frequency bands are AM radio broadcast frequency bands. However, the desired frequency band is not limited to this, and may be any frequency as long as the EMI noise caused by the PWM carrier frequency is an obstacle.

  In FIG. 9, “constant carrier frequency” is measured by operating the power converter 2 with the carrier frequency kept constant, and “averaging” of the broken line operates the power converter 2 by changing the carrier frequency with time. (For example, Japanese Patent Laid-Open No. 7-99795), “only frequency group A” selects frequency group A as described above based on desired band 1, and sets the carrier frequency of frequency group A to It is measured by operating the power conversion device 2 while changing over time, and the “present invention” shown in bold lines is based on the frequency group A selected based on the desired band 1 and the desired band 2 as described above. The carrier frequency is changed with time by using the selected frequency group B alternately. The time on the horizontal axis represents the switching time described above for the “present invention”. However, other than the “invention” (constant carrier frequency, averaging, frequency group A only) is not a concept of switching (the result does not change with respect to time), so it is described as time.

  From FIG. 9, when the switching time is from 10 ms to 200 ms, the “present invention” can reduce the sound pressure level below the “averaged” sound pressure level in both desired frequency bands. If the frequency group is switched outside this time range, the sound pressure level in the “present invention” becomes larger than that in “averaging”. Note that the range of the switching time in which the effect of the present invention is utilized to the maximum is from 13 ms to 100 ms. Here, the sound pressure level of “only the frequency group A” is different between FIG. 9A and FIG. 9B because the frequency group A selects the carrier frequency based on the desired band 1, and therefore the desired band. In FIG. 9B showing the noise level of 2, the “present invention” has a higher sound pressure level than “averaging”.

  As described above, according to the present embodiment, in the control device of the power conversion device that drives the load device by PWM control, the carrier frequency that is the control frequency for opening and closing the switch element of the power conversion device is changed with time. The carrier frequency variable means includes a frequency group memory for storing a plurality of frequency groups, each of which is a set of carrier frequency values selected based on a desired frequency band for which interference from harmonics of the carrier frequency is desired to be suppressed. And a frequency group switching means for switching the frequency group stored in the frequency group storage means at a predetermined time t to obtain a carrier frequency, so that the level of EMI noise generated in the power converter is reduced over a wide band. In addition, the EMI noise level can be simultaneously localized in a plurality of desired frequency bands. There is an effect that it is possible to reduce the.

  Further, according to the present embodiment, the predetermined time t is 10 [ms] or more and 200 [ms] or less, so that the EMI noise level can be reduced more than the conventional example in which the carrier frequency is simply changed. There is an effect that can be.

  In addition, according to the present embodiment, by repeating each of the frequency groups a plurality of times to form the predetermined time t, the EMI noise level can be locally reduced simultaneously in each desired frequency band. is there.

  Next, a second embodiment of the control device for the power conversion device according to the present invention will be described with reference to FIGS. FIG. 10 is a configuration diagram of the second embodiment in which an EMI suppression band determination unit 11 is added to the configuration example of the power conversion system of FIG. Components other than the EMI suppression band determining unit 11 are the same as those in the first embodiment shown in FIG.

  The EMI suppression band determination unit 11 outputs to the carrier frequency variable unit 9 frequency information of a band in which EMI noise caused by the carrier frequency of the power conversion device 2 (inverter) may be an obstacle. The carrier frequency variable unit 9 receives the frequency information from the EMI suppression band determination unit 11, and uses the received frequency information as a desired frequency band from the plurality of frequency groups stored in the frequency group storage unit 91 as in the first embodiment. Select a frequency group.

  FIG. 11 shows a configuration example of the EMI suppression band determination unit 11. As shown in FIG. 11, the EMI suppression band determination unit 11 includes a reception channel frequency detection unit 111 that detects a reception channel frequency of a receiver such as a radio, and a fixed EMI suppression unit 112.

  The reception channel frequency detection unit 111 outputs channel information (channel frequency) currently received by the receiver to the carrier frequency variable means 9. Here, the fixed EMI suppression unit 112 refers to an EMI noise such as a system that malfunctions due to EMI noise of a specific frequency, or a communication frequency (for example, a communication frequency used in an intelligent key) performed inside the vehicle. This is a band where the band that should be suppressed does not change. Even when EMI noise is suppressed in a plurality of desired bands, if some of the bands are fixed without changing, the frequency groups stored in the frequency group storage unit 91 in advance are limited. As a result, the load required to select the frequency group is reduced.

  According to the second embodiment described above, since the reception channel frequency detecting means for detecting the reception channel frequency of the receiver and the fixed EMI suppression unit are provided, in addition to the effects of the first embodiment, the EMI noise is locally reduced. It is possible to simultaneously reduce the EMI noise level in both frequency bands, that is, a frequency band to be reduced (radio reception channel band) and a frequency band in which the EMI noise is not locally reduced. There is an effect that can be done.

  In the above embodiments, the power conversion device 2 has been described as a DC / AC inverter that drives an AC motor, but the present invention is not limited to this. For example, a switching circuit such as one that drives a load with the configuration of the H-bridge switch described in FIG. 12 of Patent Document 1 or a DC / DC converter that drives a load by converting DC power to an arbitrary DC voltage, etc. The present invention can be applied to those that generate EMI noise at the switching frequency (carrier frequency) and its harmonics.

  Furthermore, in the present invention, the change in the carrier frequency is not limited to a triangular wave change. For example, it is obvious that the present invention can be applied to time changes of various carrier frequencies including a sinusoidal change and a sawtooth change.

It is a figure explaining the structure of Example 1 of the control apparatus of the power converter device which concerns on this invention. It is a figure explaining the structural example of a current control part. It is a figure explaining the structural example of a switching signal generation part. It is a figure explaining the triangular wave-like time change of a carrier frequency. It is a figure explaining a carrier signal. It is a figure explaining the example of a power converter device. It is a figure explaining the example of the frequency group in a carrier frequency variable part. It is a figure explaining the structural example of the frequency group switching part in a carrier frequency variable part. It is a figure explaining the example of the predetermined time in a carrier frequency variable part. It is a figure explaining the structure of Example 2 of the control apparatus of the power converter device which concerns on this invention. It is a figure explaining the structural example of an EMI suppression zone | band determination part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Power control system 2 Power converter 3 Load apparatus 4 Current detection part 5 Current command generation part 6 Control apparatus 7 Switching signal generation part 8 Carrier signal generation part 9 Carrier frequency variable part (carrier frequency variable means)
DESCRIPTION OF SYMBOLS 10 Current control part 11 EMI suppression zone | band determination part 91 Frequency group memory | storage part (frequency group memory | storage means)
92 Frequency group A
93 Frequency group B
94 Frequency group C
99 Frequency group switching section (frequency group switching means)

Claims (5)

In the control device of the power converter that drives the load device by PWM control,
The control device includes carrier frequency variable means for changing a carrier frequency, which is a control frequency for opening and closing the switch element of the power converter, with time,
The carrier frequency variable means is a frequency group storage means for storing a plurality of frequency groups, each of which is a set of carrier frequency values selected based on a desired frequency band in which interference from harmonics of the carrier frequency is desired to be suppressed.
Frequency group switching means for switching the frequency group stored in the frequency group storage means at a predetermined time t to be the carrier frequency;
The control apparatus of the power converter device characterized by comprising.   The control apparatus for a power converter according to claim 1, wherein the predetermined time t is 10 [ms] or more and 200 [ms] or less.   The control apparatus for a power converter according to claim 2, wherein the carrier frequency varying means repeats the frequency group a plurality of times at the predetermined time t. Receiving channel frequency detecting means for detecting a receiving channel frequency of a receiver as the desired frequency band;
A fixed EMI suppression unit having a fixed frequency as the desired frequency band;
The control apparatus of the power converter device of any one of Claim 1 thru | or 3 characterized by the above-mentioned. In a method for controlling a power conversion device that changes a carrier frequency, which is a control frequency for opening and closing a switching element of a power conversion device that drives a load device by PWM control, with time,
A frequency group storage process for storing a plurality of frequency groups, each of which is a set of carrier frequency values selected based on a desired frequency band in which interference from harmonics of carrier frequencies is desired to be suppressed;
A frequency group switching process of switching the stored frequency group at a predetermined time t to be the carrier frequency;
A method for controlling a power converter, comprising:

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