CONTROLLING CIRCUIT FOR PULSE WIDTH MODULATION-CONTROLLED INVERTER

摘要

PURPOSE:To eliminate an AC voltage detecting device by simulating the AC output voltage by a combination of the voltage at the DC side and an actuating signal of an upper semiconductor switch element or lower semiconductor switch element. CONSTITUTION:In a power converting device in which a magnetic flux is controlled by pulse width modulation control, the AC output voltage is required to be detected in view of control. Then, the titled circuit is so configured that a simulation value of the AC output voltage of the power converting device may be detected by a combination of an actuating signal of a semiconductor switch element of an upper arm and the voltage at the DC side when current flows in the load direction from a bridge connection circuit of the semiconductor switch element which constitutes the power converting device and the simulation value may be detected by a combination of an actuating signal of a semiconductor switch element of a lower arm and the voltage at the DC side when current flows in the reverse direction.