Inverter firing control with error compensation

摘要

A pole switch firing control for a pulse width modulated inverter controls pole switch operation under steady-state operating conditions such that the inverter output duplicates a reference signal waveform after a fixed time delay. Pole switch operating time for a given pulse in an inverter output cycle is measured by counting a sequence of clock pulses to get a count equivalent to the delay time of the pole switch. This count then serves as the starting point for a presettable counter which begins to count upon the occurrence of a transition point in the reference waveform. When the presettable counter reaches a preselected count, the pole switch operating cycle is initiated, thereby causing the pole switch to operate at a fixed time following a transition point in the reference signal.