A Novel Controlling Pulses Distribution Algorithm for PDM Inverter

On account of the features of Pulse Density Modulation (PDM) strategy for the inverter, a novel controlling pulses distribution algorithm is proposed.  Using this algorithm, the controlling pulses are distributed more evenly, and the controlling pulse waves are tidiness and no burrs, which avoid the incorrect trigger. In addition, the competitive risk problem, which often occurs in digital circuit, was solved by using Finite State Machine (FSM) theory to generate the controlling pulses. The stateflow circuit model of improved PDM controlled inverter was built and its feasibility was verified by the Field-Programmable Gate Array (FPGA) hardware circuit. The prototype, using FPGA of EP2C5T144C8N as the main chip, has been designed, fabricated and validated. The experimental results certify that the presented approach can enhance the continuity of the output current, decrease the current fluctuation, and widen the scale of power regulation.