| 摘要 |
PURPOSE:To remove high harmonic wave components of DC power supply side and contrive the alleviation of an induction failure by providing a magnification switching means and simultaneously switching the magnification of triangular wave signal frequencies for instructing the number of chopping of a plurality of inverters. CONSTITUTION:Respective AC motors 10 are sunchronously operated with equal load by providing phase difference of 30 deg. at the output voltages of respective inverters 8 and commonly using frequency command and current command. A chopping number switch 15 calculates motor driving frequency and voltage signals to produce switching commands from one to a conductor 106 and the other to a conductor 107. A chopping number simultaneous switch 16 receives chopping number switching commands from the conductors 106 and 107 of the switch 15 and produces a command for selecting predetermined simultaneous signal in the conductors 103a- 103c to respective triangular wave generator 5 from the conductor 108. In this manner it can alleviate the induction failure. |
