A NOVEL FIRING PULSE GENERATION CIRCUIT FOR A SINGLE PHASE PULSE WIDTH MODULATED (PWM) INVERTER

摘要

Accordingly there is a provision of a simple, easy and low cost method of firing pulse generation circuit used as a part of the "Electronic Controller" for controlling the output voltage of a single phase Pulse Width Modulated (PWM) inverter. In this method, a variable amplitude constant frequency sine wave is generated. The amplitude of the sine wave is controlled by a control voitage which can be varied from zero to ten volts (dc) in order to get a variable amplitude of the sine wave of zero to ten volts, which controls the modulation index of the PWM waveform. This results in appropriate change in the output voltage of the inverter, without changing the set output frequency of the inverter. The novelty of this firing pulse generation circuit is that a control signal (VCON) is used to change the amplitude of the square wave to a desired level. The change in control signal (VCON) amplitude, results in the variation of power supply voltage (AUXVCC) fed to the OPAMP integrated circuit (IC) generating the square wave. This results In getting the desired amplitude of the sine wave (VSC), without changing the set frequency of the sine wave.