INVERTER CONTROL DEVICE AND ELECTRIC COMPRESSOR FOR AC MOTOR

摘要

In driving an AC motor using a DC current via a 3-phase PWM inverter, while a 3-phase AD motor current is precisely detected by only a means for measuring a DC input current to the 3-phase PWM inverter, resonance on a DC power source side caused by a ripple current is suppressed. Using a carrier Cry_e earlier than that of a V phase to sample a U phase and using a carrier Cry_l always later than that of the V phase to sample a W phase, a sampling time sufficiently longer than each interval Ts respectively between the carrier Cry_e, Cry_m, and Cry_l can be secured and the current is detected easily.