| 摘要 |
A pulse width modulation (PWM) control unit of an inverter (3) in which a carrier frequency having a normal value of about 5KHz, calculates the ON time (PWM control pattern) at every calculation period corresponding to such carrier frequency and divides the calculated ON time into a plurality of pulses. This enables such conditions to be presented that simulate that the PWM control was carried out at high carrler frequency (20 KHz or higher), while using a one-chip microcomputer (8) which requires a comparatively long calculation time. Thus, PWM Control by high carrier frequency can be attained at lower cost and with a simple circuit constructlon. |
