Electromagnetic noise reducer for electric automobile

Abstract

Abstract PURPOSE:To reduce an electromagnetic noise generated at the time of low-speed, low-powered travel by raising the carrier frequency of a PWM signal supplied to an inverter, when an AC motor is loaded at a low rotational speed. CONSTITUTION:Between a battery 10 and an AC motor 14, there is provided an inverter main circuit 12, which is controlled by a PWM signal according to a triangular wave carrier signal and to a sinusoidal signal outputted from a control circuit 20. On the other hand, a carrier frequency control circuit 24 sets a carrier frequency to about 10-20kHz, when an inverter current is low, and to about several kHz-10kHz, when said current is high. In this manner, an electromagnetic noise can be removed at the time of idling and low speed, low powered travel.

Inventors

• 👤 Sumikazu Shiyamoto

Bibliographic Details