| 摘要 |
PROBLEM TO BE SOLVED: To reduce heating in an inverter for supplying power to an AC motor without impairing drive performance. SOLUTION: A torque command calculator 21 generates a necessary torque command *T. A target current calculator 22 calculates a d-axis target current initial value *idorg and a q-axis target current initial value *iqorg for designating respective phase currents iu, iv and iw to be supplied from a inverter 13 to the AC motor 11. A waveform converter 23 converts the waveforms of the d-axis target current initial value *idorg and the q-axis target current initial value *iqorg, so that the waveforms of the respective phase currents iu, iv and iw become rectangular waves or pseudo-rectangular waves having a width of 120 deg. of an electric angle to the d-axis target current *id and the q-axis target current *iq. A vector controller 24 feedback controls the current based on the d-axis target current *id and the q-axis target current *iq. |
