Controlling method for pwm switching of 3-phase bridge voltage type inverter

Abstract

Abstract PURPOSE:To readily obtain a PWM switching waveform for an arbitrary 3-phase AC voltage waveform by comparing two triangular waveforms with two comparison waveforms obtained from a set voltage waveform between lines and determining a switching timing. CONSTITUTION:Two types of triangular waves which has a phase difference of 90 deg. and is regulated in the minimum level to zero are provided, and these waves are compared with absolute value waveforms of two other interline voltages except the highest interline voltage of the absolute values of 3-phase interline voltage waveforms to be obtained, thereby attaining control pulses. Energization pulse signals for respective switching arms in a 3-phase bridge circuit 2 are generated by said control pulses.

Inventors

• 👤 Norio Onishi

Bibliographic Details