DOUBLE SINUSOIDAL WAVE PWM GENERATOR OF THREE PHASE INVERTER FOR ELECTRIC VEHICLE CAPABLE OF REDUCING SWITCHING DAMAGE

摘要

PURPOSE: A double sinusoidal wave PWM(Pulse Width Modulation) generator of a three phase inverter for an electric vehicle is provided to reduce switching damage by supplying a double sinusoidal wave after comparing the double sinusoidal wave and a saw tooth wave. CONSTITUTION: A clock signal generator generates an initial clock signal. A counter(20) designates an address of a ROM(Read Only Memory)(30) by using the initial clock signal outputted from the clock signal generator. The ROM stores predetermined data corresponding to an output signal of the counter. A D/A(Digital/Analog) converter(40) converts data stored at each address of the ROM into an analog signal. An OPAMP(OPerational AMPlifier)(50) amplifies and filters a small signal outputted from the D/A converter and compares a three-phase double sinusoidal wave with a saw tooth wave to generate a double sinusoidal PWM wave.