Design and Implementation of One-Leg and PI Control Single-Phase H-Bridge Current Regulated Inverter

The demand for higher efficiency power inverters was growing rapidly. In the H-bridge topology, all the power switches usually operate at high frequency, and the higher the switching frequency the more power it consumes. The switching losses of the inverter can be reduced further by doing the switching on one leg only so only two power switches operate at high frequency, while the other two operate at a low frequency on their cycle based on Zero-Crossing Detection. The output is closed-loop controlled using a proportional-integral (PI) control system. By comparing the value of PI with a sawtooth carrier signal, it generates Sinusoidal Pulse Width Modulation (SPWM) thus providing correct sinusoidal wave output with total harmonic distortion (THD) below the limit after filtered. By doing this strategy, the switching loss could be reduced. A STM32F407VET6 microcontroller was used in this research to do the controlling techniques. This research is verified by simulating the design and the hardware implementation that was done in a laboratory.