| 摘要 |
PURPOSE:To reduce higher harmonic components, by detecting a target voltage in watching the counter electromotive force of a load, and by selecting the optimum output voltage vector by means of it. CONSTITUTION:The current control device of a voltage type inverter is equipped with not only a voltage type inverter, current detectors 3 3-5, an output current command generation circuit 6 and a driver circuit 13 but also a deviated current generation circuit 23, a output voltage vector selection circuit 24, latch circuit 25-26, an oscillator 27, multipliers 28-30, an adder 31, comparators 32-33, etc. The selection circuit 24 is constituted with functions of a target voltage estimation circuit, a voltage vector holding circuit, etc. as well as a mode switching device and a ROM. To the selection circuit 24 the present output voltage vector Vkn, the former output voltage vector Vkn-1, a region signal of the deviated current i and a mode switching signal St are inputted. Based on these the next output voltage vector Vkn+1, etc., are outputted. Further, the latch circuits 25-26 hold the deviated current i, etc., respectively and establish the input of the above-mentioned selection circuit 24. |
