| 摘要 |
A method of controlling an inverter (4) comprises the steps of using a current value of one phase (iu) of an AC motor, current estimation values of two other phases (iws, ivs) and a reference phase obtained by integrating the output frequency instruction to be converted for obtaining, in a rotating coordinate system (Vd*, Vq*), instantaneous values of exciting (Id) and torque (Iq) currents; using averaged values (Ims, Its) averaged values of the instantaneous values and said reference phase for obtaining, in a fixed coordinate system (Vu*, Vv*, Vw*), current estimation values, and feeding back the current estimation values of the two other phases into an input of said rotating coordinate system; and controlling an output voltage or output frequency from said inverter in accordance with the instantaneous values or the averaged values of said torque current (Iq). <IMAGE> |
