| 摘要 |
PROBLEM TO BE SOLVED: To enable inverter output with ripples compensated in a direct current part over the entire range of the operation of an air conditioning device, and maximum output even in ranges exceeding a base frequency, with respect to a capacitorless-type inverter which does not have any conventional filter circuit in the direct current part. SOLUTION: The device comprises a converter 2 which converts three-phase currents into direct currents; an inverter 3 supplied with power therefrom; a compressor 4 driven by the inverter 3; an input ripple rate calculating section 6 which calculates the ripple rate of a direct current part; a ripple compensation calculating section 7 which calculates an output voltage with the ripples of the direct current part taken into account, from the output of the input ripple rate calculating section 6 and the output of a fundamental output voltage calculating section 8 which calculates the present output voltage; an interphase voltage compensation calculating section 9 which compensates voltages between phases from the output of the ripple compensation calculating section 7, the voltage of the direct current part, and the output of the fundamental output voltage calculating section 8; and a PWM processing section 10 which outputs PWM waveform for driving the inverter 3 from the output of the interphase voltage compensation calculating section 9. As a result, the ripples of the direct current part can be compensated, and even if the base frequency is exceeded the maximum output voltage can be outputted in the capacitorless system. |
