| 摘要 |
PURPOSE:To realize a low cost inverter even for a high capacity air-conditioner by constituting the inverter of first and second inverters for feeding power, respectively, to three-phase windings of two three-phase induction motor systems for a compressor and a PWM waveform generating circuit for variably controlling the output voltage and output frequency. CONSTITUTION:In case of a two pole three-phase induction motor, windings U1 and U2, V1 and V2, W1 and W2 in two three-phase winding systems of a compressor 22 are mounted, respectively, in same slots of a stator core 17. When a PWM waveform producing circuit 16 provides same PWM signals to first and second inverters 9a, 9b, the first inverter amplifies the PWM signal through a base drive circuit 15a and feeds a base current to a power transistor module 14a which then produces three-phase outputs Ua, Va, Wa, Voltage and frequency of the three-phase output Ua, Va, Wa are determined based on the PWM output signal fed from the PWM waveform producing circuit 16. |
