JP2015089218A - Invertor controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inverter controller capable of quickly converging an AC voltage generated by an inverter to a target value.SOLUTION: An inverter controller 1 includes: a PWM control part 3; and an adjustment part 4. In the adjustment part 4, an average measured value 63d in one cycle of an AC voltage 5C generated by an inverter 1 is calculated. The adjustment part 4 adjusts the amplitude of a sine wave 20B to generate a sine wave 40 so that the average measured value 63d becomes close to a target value (amplitude target value 61) of the amplitude possessed by an AC voltage. The PWM control part 3 generates PWM signals 11a, 11b by performing PWM modulation of the sine wave 30 obtained by changing a reference potential of the sine wave 40.

Description

  The present invention relates to an inverter control device.

  A PWM (Pulse Width Modulation) method is known as a control method for an inverter that converts a DC voltage to generate an AC voltage. In the PWM method, a PWM signal is generated by comparing a sine wave, a current command value of an alternating current, or the like with a carrier wave in order to control on / off of a switching element in the inverter.

  Patent Document 1 discloses a power converter that controls an inverter circuit using a PWM method.

  This power converter feeds back the detected value of the alternating current output from the inverter circuit so that the alternating current becomes a constant current. Specifically, this power converter calculates an error by subtracting the detected value of the alternating current from the current command value, and generates a signal wave by proportional-integral control using the calculated error. This power converter compares the generated signal wave with a carrier wave, generates a gate drive signal, and supplies it to a switching element in the inverter circuit.

  However, proportional integral control is based on the premise that the level of the command value is constant, such as control of direct current. This is because the response speed of the feedback control device including the proportional-plus-integral control circuit depends on constants (control period, delay time, etc.) unique to the device, and the response speed cannot be made zero. Therefore, when the level of the signal command value fluctuates faster than the response speed, the proportional-integral control cannot generate a signal according to the fluctuation of the level of the signal command value. In other words, proportional-integral control cannot control the waveform of the alternating voltage that varies with time to a desired waveform, and therefore cannot converge the alternating voltage to the target value.

JP-A-6-197546

  An object of the present invention is to provide an inverter control device capable of quickly converging an alternating voltage generated by an inverter to a target value.

  An inverter control device according to the present invention includes a PWM control unit that generates a PWM signal for controlling an inverter by PWM-modulating an input wave, and an average value or an effective value of an AC voltage generated by the inverter over a predetermined period. The amplitude of the input wave is adjusted so that the first representative value becomes closer to a second representative value consisting of an average value or an effective value of the target value of the amplitude of the AC voltage in the predetermined period. And an adjustment unit that supplies an input wave having an amplitude to the PWM control unit.

  According to this configuration, the amplitude of the input wave is such that the average value or effective value per predetermined period of the AC voltage generated by the inverter approaches the average value or effective value per predetermined period of the target value of the AC voltage amplitude. Are adjusted, and the input wave having the adjusted amplitude is PWM-modulated. Since the cycle of the AC voltage is the same as the cycle of the input wave, the amplitude of the input wave is adjusted in units of one cycle of the input wave. As a result, the influence of the delay caused by feeding back the measured value of the AC voltage can be prevented, so that the AC voltage can be quickly converged to the target value.

  Further, the adjustment unit uses a first calculation unit that calculates the first representative value from the measured value of the AC voltage, and an adjustment value for adjusting the amplitude of the input wave using proportional control and integral control. A PI control unit that generates a difference value obtained by subtracting the first representative value from the second representative value, and an amplitude adjustment unit that adjusts the amplitude of the input wave using the adjustment value.

  According to this configuration, the amplitude of the input wave can be adjusted by proportional-integral control using the first representative value and the second representative value.

  The inverter control device according to the present invention further includes a second calculation unit that calculates the second representative value from the target value of the amplitude.

  According to this configuration, even if the target value of the amplitude is changed, the second representative value corresponding to the changed target value is generated, so that an alternating voltage corresponding to the changed target value is quickly generated. Can do.

It is the schematic which shows the structure of the power conversion system using the inverter control apparatus which concerns on embodiment of this invention. It is a functional block diagram which shows the structure of the inverter control apparatus shown in FIG. It is a graph which shows the time change of the alternating voltage produced | generated when controlling an inverter using the conventional inverter control apparatus. It is a graph which shows an example of the time change of the alternating voltage produced | generated when controlling an inverter using the inverter control apparatus shown in FIG. It is a graph which shows the other example of the time change of the alternating voltage produced | generated when controlling an inverter using the inverter control apparatus shown in FIG. It is a graph which shows the time change of the average target value and average measured value which are used when the alternating voltage shown to FIG. 5A is produced | generated. It is a graph which shows the other example of the time change of the alternating voltage produced | generated when controlling an inverter using the inverter control apparatus shown in FIG. It is a graph which shows the time change of the average target value and average measured value which are used when the alternating voltage shown to FIG. 6A is produced | generated.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[1. Configuration of power conversion system]
FIG. 1 is a schematic diagram showing a configuration of a power conversion system 100 using the inverter control device 1 according to the present embodiment. As shown in FIG. 1, the power conversion system 100 includes an inverter control device 1, an inverter 5, a DC power supply 6, and a voltmeter 7.

  The inverter 5 converts the DC voltage 5A to generate an AC voltage 5B, and supplies the AC voltage 5C obtained by smoothing the AC voltage 5B to a load (not shown).

  The voltmeter 7 measures the AC voltage 5 </ b> C and supplies the actual measurement value 43 a of the AC voltage 5 </ b> C to the inverter control device 1.

  The inverter control device 1 controls the inverter 5 using the PWM method. The inverter control device 1 generates PWM signals 11a and 11b for controlling on / off of the switching elements 51a and 52a in the inverter 5 using the measured value 43a.

[1.1. Configuration of inverter 5]
The inverter 5 includes a half bridge circuit 50 and a low pass filter 55. The half bridge circuit 50 converts the DC voltage 5A supplied from the DC power supply 6 to generate an AC voltage 5B. The AC voltage 5B is a rectangular wave. The low-pass filter 55 removes high-frequency components contained in the AC voltage 5B and generates a smoothed AC voltage 5C. The AC voltage 5C is supplied from the output terminals 58 and 59 of the inverter 5 to a load (not shown).

  The half bridge circuit 50 includes arms 51 and 52 connected in series to both ends of the DC power supply 6. The arm 51 is connected to the high potential side of the DC power supply 6, and the arm 52 is connected to the low potential side of the DC power supply 6. A terminal 53 a is provided between the arm 51 and the arm 52. A terminal 53 b is provided between the arm 52 and the DC power supply 6 and connected to the output terminal 59.

  The arm 51 includes a switching element 51a and a diode 51b connected in reverse parallel to the switching element 51a. The arm 52 includes a switching element 52a and a diode 52b connected in antiparallel with the switching element 52a. The switching elements 51a and 52a are, for example, MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors).

  The low pass filter 55 includes a coil 56 and a capacitor 57. One end of the coil 56 is connected to the terminal 53 a of the half bridge circuit 50, and the other end of the coil 56 is connected to the output terminal 58 of the inverter 5. One end of the capacitor 57 is connected to the other end of the coil 56 and the output terminal 58, and the other end of the capacitor 57 is connected to the terminal 53 b and the output terminal 59 of the inverter 5. The terminal 53b and the output terminal 59 are grounded.

[1.2. Configuration of Inverter Control Device 1]
FIG. 2 is a functional block diagram showing the configuration of the inverter control device 1. As shown in FIG. 2, the inverter control device 1 includes a target wave generation unit 2, a PWM control unit 3, and an adjustment unit 4.

  The target wave generator 2 generates a sine wave 20B that is a target of PWM modulation. The adjustment unit 4 adjusts the amplitude of the sine wave 20B to generate the sine wave 40. The PWM control unit 3 performs PWM modulation on the sine wave 40 supplied from the adjustment unit 4 to generate PWM signals 11a and 11b. The PWM signal 11a is supplied to the gate of the switching element 51a, and the PWM signal 11b is supplied to the gate of the switching element 52a.

  The target wave generation unit 2 includes a sine wave generator 21 and a calculator 22.

  The sine wave generator 21 generates a sine wave 20 </ b> A using the sawtooth wave 66 supplied to the inverter control device 1.

  The calculator 22 multiplies the sine wave 20A by the amplitude target value 61 supplied to the inverter control device 1 to generate the sine wave 20B. The amplitude target value 61 indicates the target level of the amplitude of the AC voltage 5C. The sine wave 20B is a signal subject to PWM modulation.

  The PWM control unit 3 includes an arithmetic unit 31, a carrier wave generation unit 32, a comparator 33, and a NOT circuit 34.

  The computing unit 31 adds the reference potentials of the AC voltages 5B and 5C to the sine wave 40 to generate the sine wave 30. As a result, the sine wave 40 becomes a signal that varies with the amplitude indicated by the amplitude target value 61 with the reference potential as the center.

  The carrier wave generation unit 32 generates a carrier wave 35 used for PWM modulation. The comparator 33 generates the PWM signal 11 a by comparing the sine wave 30 with the carrier wave 35. The NOT circuit 34 inverts the logic level of the PWM signal 11a to generate the PWM signal 11b.

  The adjustment unit 4 includes average calculation units 41 and 42, calculators 43 and 44, and a PI control unit 45.

  The average calculation unit 41 calculates the average target value 62 using the amplitude target value 61. The average target value 62 is an average of the amplitude target values 61 in one cycle of the AC voltage 5C.

  The average calculation unit 42 calculates the average actual measurement value 63d using the actual measurement value 43a supplied from the voltmeter 7. The average measured value 63d is the average of the measured values 43a in one cycle of the AC voltage 5C. Details of the configuration of the average calculator 42 will be described later.

  The computing unit 43 generates a difference value 64 by subtracting the average measured value 63d from the average target value 62, and supplies the generated difference value 64 to the PI control unit 45.

  The PI control unit 45 executes proportional control and integral control based on the difference value 64 to generate an adjustment value 65. The adjustment value 65 is used to adjust the amplitude of the sine wave 20B to be modulated.

  The computing unit 44 adjusts the amplitude of the sine wave 20B by multiplying the sine wave 20B by the adjustment value 65. The sine wave 20 </ b> B whose amplitude is adjusted is supplied to the PWM control unit 3 as a sine wave 40.

  Next, the configuration of the average calculation unit 42 will be described. The average calculation unit 42 includes an arithmetic unit 421, an absolute value conversion unit 422, an integration unit 423, a division unit 424, and a latch circuit 425.

  The computing unit 421 generates a difference value 63a by subtracting the reference potential from the actual measurement value 43a. The difference value 63a indicates alternating current that fluctuates around a level indicating 0V. The absolute value conversion unit 422 obtains the absolute value 63b of the difference value 63a from the difference value 63a.

  The integrating unit 423 integrates the absolute value 63b that is continuously input over one period of the AC voltage 5C to generate an integrated value 63c. The division unit 424 generates the average measured value 63d by dividing the integral value 63c by the period of the AC voltage 5C.

  The latch circuit 425 latches the average actual measurement value 63 d generated by the division unit 424. Each time one period of the sawtooth wave 66 elapses, the latch circuit 425 supplies the latched average actual measurement value 63d to the computing unit 43 and latches the average actual measurement value 63d newly generated by the division unit 424.

[2. Adjustment of amplitude of sine wave]
FIG. 3 is a graph showing a simulation result of the AC voltage 5C when a conventional inverter control device is used. The conventional inverter control device has a configuration in which the adjustment unit 4 is excluded from the inverter control device 1 shown in FIG. FIG. 4 is a graph showing a simulation result of the AC voltage 5C when the inverter control device 1 shown in FIG.

  3 and 4, the reference potential of the AC voltage 5C is set to 350 V and the amplitude target value 61 is set to 100 V, and then the time change of the AC voltage 5C is simulated.

  As shown in FIG. 3, when the inverter 5 is controlled using the conventional inverter control device 1, the amplitude of the AC voltage 5C continues to fluctuate without converging to 100V. This variation occurs due to the influence of the operating temperature of the inverter 1, the reactance component of the coil 56 in the low-pass filter 55, and the like.

  Even when the inverter control device 1 adjusts the signal level of the sine wave using the normal feedback method instead of the adjustment unit 4, it is considered that the amplitude of the AC voltage 5 </ b> C continues to fluctuate as in FIG. 3.

  In a normal feedback method, an adjustment value for making the amplitude of the AC voltage 5C coincide with the amplitude target value 61 is generated by executing PI control based on the difference value between the actual measurement value 43a and the amplitude target value 61.

  At this time, a period from when the AC voltage 5C is detected until the adjustment value is generated corresponds to a delay. Due to this delay, the phase of the sine wave 20B whose amplitude is adjusted by the adjustment value does not match the phase of the AC voltage 5C at the timing when the AC voltage 5C is detected. That is, the amplitude of the sine wave 20 </ b> B is not adjusted so that the amplitude of the AC voltage 5 </ b> C matches the amplitude target value 61. As a result, the amplitude of the AC voltage 5C cannot be matched with the amplitude target value 61, and the amplitude of the AC voltage 5C continues to fluctuate.

  On the other hand, when the inverter control device 1 generates the adjustment value 65 using the adjustment unit 4 and adjusts the amplitude of the sine wave 20B, the amplitude of the AC voltage 5C is quickly increased as shown in FIG. It can be close to the target value 61 (100 V).

  In the adjustment unit 4, the average calculation unit 42 calculates an average actual measurement value 63d that is an average per one cycle of the actual measurement value 43a of the AC voltage 5C, and outputs the average actual measurement value 63d in units of one cycle of the sine wave 20B. The adjustment unit 4 executes PI control based on the average target value 62 and the average actual measurement value 63d, and generates an adjustment value 65 for bringing the average actual measurement value 63d close to the average target value 62. The amplitude of the sine wave 20B is adjusted by multiplying the generated adjustment value 65 by the sine wave 20B.

  Since the average actual measurement value 63d is updated every cycle of the sine wave 20B, the adjustment value 65 is also updated every cycle of the sine wave 20A. Since the signal level of the sine wave 20A is adjusted by the same adjustment value 65 over one cycle of the sine wave 20A, the phase of the sine wave 20B whose amplitude is adjusted by the adjustment value 65 and the timing at which the AC voltage 5C is detected. Is not affected by the deviation from the phase of the AC voltage 5C. As a result, when adjusting the signal level of the sine wave 20A, it is possible to suppress the influence due to the delay associated with the generation of the adjustment value 65, so that the inverter control device 1 quickly sets the amplitude of the AC voltage 5C to the amplitude target value. 61.

[3. Operation of inverter control device 1]
[3.1. Operation of target wave generator 2]
In the target wave generation unit 2, the sine wave generator 21 receives the supply of the sawtooth wave 66 and generates a sine wave 20 </ b> A having the same frequency as the sawtooth wave 66. That is, the sawtooth wave 66 is used as a frequency command signal that indicates the frequency of the AC voltage 5C. The amplitude of the sine wave 20 </ b> A has a predetermined amplitude preset in the sine wave generator 21.

  The calculator 22 multiplies the sine wave 20A by the amplitude target value 61 to generate a sine wave 20B to be subjected to PWM modulation. As will be described later, the amplitude of the sine wave 20B is adjusted by the adjustment unit 4 in units of one cycle.

[3.2. Operation of adjusting unit 4]
In the average calculator 42, the calculator 421 generates a difference value 63a by subtracting the reference potential from the measured value 43a of the AC voltage 5C supplied from the voltmeter 7. The absolute value conversion unit 422 obtains the absolute value 63b of the difference value 63a from the difference value 63a.

  The integrator 423 integrates the absolute value 63b to generate an integrated value 63c. In accordance with the sawtooth wave 66 supplied to the integrator 423, the integrator 423 supplies the integral value 63 c to the divider 424 for each cycle of the sawtooth wave 66. Thereafter, the integration unit 423 clears the integration value 63c and restarts the integration of the absolute value 63b. Since the frequency of the AC voltage 5C matches the frequency of the sawtooth wave 66, the integral value 63c supplied to the division unit 424 is equal to a numerical value obtained by integrating the absolute value 63b over one period of the AC voltage 5C.

  The division unit 424 generates the average measured value 63d by dividing the integration value 63c supplied from the integration unit 423 by the period of the sawtooth wave 66. The generated average measured value 63d is latched by the latch circuit 425. The latch circuit 425 receives the supply of the sawtooth wave 66, and supplies the average measured value 63 d to the computing unit 43 every time one period of the sawtooth wave 66 elapses.

  The average calculation unit 41 multiplies the amplitude target value 61 by (2 / π) to thereby obtain an average value (average target value 62) per cycle of the amplitude (amplitude target value 61) of the sine wave 20B to be modulated. ). This is because the absolute value of the definite integral in the (1/2) period of the sine wave is 1 / π.

  The calculator 43 subtracts the average measured value 63d from the average target value 62 to generate a difference value 64. The PI control unit 45 executes PI control based on the difference value 64 and generates an adjustment value 65 for bringing the average actual measurement value 63 d closer to the average target value 62.

  As described above, since the integration value 63c is output from the integration unit 423 for each cycle of the AC voltage 5C, the average measured value 63d is generated for each cycle of the AC voltage 5C. The average target value 62 is constant unless the amplitude target value 61 is changed. Therefore, the adjustment value 65 output from the PI control unit 45 is updated every cycle of the AC voltage 5C (sine wave 20B).

  The computing unit 44 adjusts the level of the sine wave 20B by multiplying the sine wave 20B to be subjected to PWM modulation by the adjustment value 65 supplied from the PI control unit 45. Since the adjustment value 65 is constant over one period of the sine wave 20B, the signal level of the sine wave 20B is adjusted under the same conditions over one period. The computing unit 44 supplies the sine wave 40 to the PWM control unit 3 as a result of multiplying the sine wave 20B by the adjustment value 65.

[3.3. Operation of PWM control unit 3]
The calculator 31 adds the reference potential to the sine wave 40 supplied from the adjustment unit 4. The carrier wave generation unit 32 generates a carrier wave 35 having the same frequency as the sawtooth wave 66 and having the same phase as the sine wave 40. Although not shown in FIG. 2, the carrier generation unit 32 may be supplied with the sawtooth wave 66 in order to generate the carrier 35 that satisfies the above conditions.

  The comparator 33 generates the PWM signal 11 a by comparing the sine wave 40 with the carrier wave 35. When the level of the sine wave 40 is equal to or higher than the level of the carrier wave 35, the comparator 33 generates a PWM signal 11a having a logic level “1”. When the level of the sine wave 40 is lower than the level of the carrier wave 35, the comparator 33 generates a PWM signal 11a having a logic level “0”. The comparator 33 supplies the PWM signal 11 a to the gate of the switching element 51 a in the inverter 5 and the NOT circuit 34.

  The NOT circuit 34 generates the PWM signal 11b by inverting the logic level of the PWM signal 11a. The generated PWM signal 11 b is supplied to the gate of the switching element 52 a in the inverter 5.

[4. simulation result]
Hereinafter, the result of simulating the operation of the inverter control device 1 and the inverter 5 will be described.

  5A and 5B are graphs showing simulation results of the inverter control device 1 and the inverter 5 when the amplitude target value 61 is constant. FIG. 5A is a graph showing a time change of the AC voltage 5C. FIG. 5B is a graph showing temporal changes in the average target value 62 and the average actual measurement value 63d.

  As simulation conditions, the DC voltage 5A was set to 700V, and the reference voltages of the AC voltages 5B and 5C were set to 350V. That is, the reference potential supplied to the calculators 31 and 421 is 350V. The amplitude target value 61 was set to 100 V, and the frequencies of the sawtooth wave 66 and the carrier wave 35 were set to 2 kHz.

  As shown in FIG. 5A, after the inverter control device 1 starts control of the inverter 5, the amplitude of the AC voltage 5C gradually increases and repeats vibration until 2 milliseconds elapse. Then, after 2 milliseconds have elapsed, the amplitude of the AC voltage 5C converges to 100V.

  As shown in FIG. 5B, since the amplitude target value 61 is constant at 100 V, the average target value 62 is similarly constant. The average actual measurement value 63d gradually increases after the control of the inverter 5 is started, and approaches the average target value 62. The average measured value 63d becomes substantially the same as the average target value 62 after 2 milliseconds have elapsed.

  6A and 6B are graphs showing simulation results of the inverter control device 1 and the inverter 5 when the amplitude target value 61 is changed while the inverter 5 is controlled using the inverter control device 1. FIG. 6A is a graph showing a time change of the AC voltage 5C. FIG. 6B is a graph showing temporal changes in the average target value 62 and the average actual measurement value 63d.

  The initial conditions of the simulation are the same as the simulation conditions when the amplitude target value 61 is constant. That is, the amplitude target value 61 was set to 100V, and then the amplitude target value 61 was changed to 50V.

  6A and 6B, the target amplitude value 61 is changed when the time is 1 millisecond. As a result, as shown in FIG. 6A, the amplitude of the AC voltage 5C gradually decreases from 100V. The amplitude of the AC voltage 5C is stabilized at approximately 50 V when the time is 4 milliseconds.

  As shown in FIG. 6B, the average target value 62 varies with the amplitude target value 61. The average actual measurement value 63 d rapidly decreases after changing the amplitude target value 61 and approaches the average target value 62. The average measured value 63d is substantially the same as the average target value 62 when the time is 4 milliseconds.

  As described above, the inverter control device 1 calculates the average value (average measured value 63d) in one cycle of the AC voltage 5C output from the inverter 5, and the average measured value 63d is the amplitude target value 61 of the AC voltage 5C. The amplitude of the sine wave 40 is controlled so as to approach the average value (average target value 62) in the above one period. Thereby, the amplitude of AC voltage 5C output from inverter 5 can be quickly controlled to a desired level (amplitude target value 61).

  In the said embodiment, although the PI control part 45 demonstrated the example which produces | generates the adjustment value 65 using the proportional integral control based on the difference value 64 in the adjustment part 4, it is not restricted to this. The adjusting unit 4 may generate the adjustment value 65 by executing PID control based on the average target value 62 and the average actual measurement value 63d. That is, the adjustment unit 4 may control the amplitude of the sine wave 20B so that the average measured value 63d approaches the average target value 62.

  In the embodiment described above, the adjustment unit 4 generates the average target value 62 from the amplitude target value 61 and generates the average actual measurement value 63d from the actual measurement value 43a. However, the present invention is not limited to this. The adjustment unit 4 may generate an effective value of the actual measurement value 43a and generate an effective value of the sine wave 20B using the amplitude target value 61. In this case, the adjustment unit 4 controls the amplitude of the sine wave 20B so that the effective value of the actual measurement value 43a approaches the effective value of the sine wave 20B.

  In the said embodiment, although the adjustment part 4 demonstrated the example provided with the average calculation part 41 which produces | generates the average target value 62 from the amplitude target value 61, it is not restricted to this. The inverter control device 1 may not include the average calculation unit 41. In this case, the inverter control device 1 may receive supply of the average target value 62 from the outside.

  In the above embodiment, the average calculation unit 41 calculates the average of the amplitude target value 61 in one cycle of the AC voltage 5C, and the average calculation unit 42 calculates the average of the actual measurement value 43a in one cycle of the AC voltage 5C. An example has been described, but the present invention is not limited to this. The average calculators 41 and 42 may calculate the average of the AC voltage 5C in two cycles or three cycles. That is, the average calculation unit 41 may calculate the average of the amplitude target values 61 in the predetermined period of the AC voltage 5C, and the average calculation unit 42 may calculate the average of the actual measurement values 43a in the predetermined period of the AC voltage 5C.

  In the above embodiment, the example in which the adjustment unit 4 generates the sine wave 20A to be modulated has been described. However, the present invention is not limited to this. The adjustment unit 4 may not include the target wave generation unit 2 and may be supplied with the sine wave 20A from the outside.

  While the embodiments of the present invention have been described above, the above-described embodiments are merely examples for carrying out the present invention. Therefore, the present invention is not limited to the above-described embodiment, and can be implemented by appropriately modifying the above-described embodiment without departing from the spirit thereof.

DESCRIPTION OF SYMBOLS 1 Inverter control apparatus 2 Target wave generator 3 PWM control part 4 Control part 5 Inverters 41 and 42 Average calculation part 45 PI control part 422 Absolute value conversion part 423 Integration part 424 Division part

Claims (3)

A PWM control unit that generates a PWM signal for controlling the inverter by PWM-modulating the input wave;
The first representative value consisting of the average value or effective value of the AC voltage generated by the inverter in a predetermined period is the second representative value consisting of the average value or effective value of the target value of the amplitude of the AC voltage in the predetermined period. And an adjustment unit that adjusts the amplitude of the input wave so that the input wave approaches, and supplies the input wave having the adjusted amplitude to the PWM control unit. The inverter control device according to claim 1,
The adjustment unit is
A first calculator for calculating the first representative value from the measured value of the AC voltage;
A PI control unit that generates an adjustment value for adjusting the amplitude of the input wave using a proportional control and an integral control from a difference value obtained by subtracting the first representative value from the second representative value;
An inverter control device comprising: an amplitude adjustment unit that adjusts the amplitude of the input wave using the adjustment value. The inverter control device according to claim 2, further comprising:
An inverter control device comprising: a second calculation unit that calculates the second representative value from the target value of the amplitude.

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