Digital Control of High Frequency Pulse-Width Modulated Inverters

摘要

The effect of word length on the hormonic content of pulse width modulated (PWM) waveform generators, and voltage control in high carrier frequency PWM waveform generators were studied. Eight and four bit microprocessor-based PWM waveform generators operating silently with a 20 kHz carrier were developed. The PWM output of each generator is determined by voltage, modulating frequency, and carrier frequency. Eight bit systems are capable of generating virtually pure sinusoids from 0 to greater than 2 kHz and can form general purpose, PWM waveform generators suitable for driving a variety of inverter power switches. An inverter power stage with a selection of MOSFET gate drive circuits, depending upon the switching characteristics required of the power devices, was constructed.