VOLTAGE REFERENCE WAVEFORM GENERATOR CIRCUIT FOR PULSE WIDTH MODULATION INVERTER

摘要

PURPOSE:To obtain the input voltage specification of a load and to enhance the efficiencies of a pulse width modulation inverter and the load by storing a plurality of reference waveform patterns in a reference waveform generator, selecting the reference waveform by the value of a voltage command and outputting it to an amplitude modulator. CONSTITUTION:When a frequency command is applied to a clock signal generator 10, a clock pulse which is proportional to the command is generated, counted by a ring counter 20, and the counted content is outputted to a reference waveform generator 30. When a frequency command is applied to a frequency voltage setter 40, a voltage command is outputted to the generator 30 and an amplitude modulator 50 on the basis of a preselected frequency voltage ratio pattern. The generator 30 stores a plurality of reference waveform patterns, selects the prescribed reference waveform determined by the value of the voltage command, sets the frequency of the waveform to the frequency which obeys the frequency command on the basis of the counter content of the counter 20, and outputs it to the modulator 50.