INVERTER SYSTEM OF CARRIER FREQUENCY MODULATION BY HIGH-FREQUENCY TRANSFORMER COUPLING

摘要

PURPOSE:To reduce the switching loss in an inverter at an output stage and to supply a required AC power also to a load with a low power factor by switching the inverter at the output stage with a signal wave of commercial frequency or a signal wave of the equivalent waveform and outputting the power of commercial frequency. CONSTITUTION:A unit sinusoidal wave signal 34 is inputted to a buffer 41 and an inverter 42 via a polarity discrimination equipment 36, simultaneously turning on and off switching elements 5 and 6 via a gate circuit 43, at the same time simultaneously turns on and off switching elements 7 and 8 via a gate circuit 44. In this case, the ON/OFF control of the switching elements 5 and 6 is delayed by 180 degrees from the ON/OFF control of the switching elements 7 and 8, thus causing switching with the signal wave of commercial frequency or the signal of an equivalent waveform and hence reducing switching loss and supplying power also to a load with a low power factor.