POWER INVERTER WITH REDUCED SWITCHING FREQUENCY

摘要

An inverter system (10) in accordance with the invention includes an electrical load (R, L) having a direct current source (E) for providing direct current to at least one pair of inverter switches (Q1 and Q2) with the at least one pair of switches being switched between conducting and nonconducting states to control a direction of flow of current pulses between the direct current source and the electrical load to cause the flow of alternating current through the electrical load; a source of a voltage reference (Vref) representing a desired form of the alternating current to flow through the electrical load; an error control signal generator (24) having a first input coupled to the electrical load and a second input coupled to the voltage reference for generating on an output (26) an error control voltage representing a difference between the first and second inputs; and an inverter controller (16), coupled to the output of the error control signal generator and to the inverter, for controlling a frequency of switching of the at least one pair of switches in response to the error control voltage to produce current pulses flowing through the electrical load occurring at a variable frequency which provides the alternating current flow through the electrical load.