Achieving Fast Dynamic Response in Hybrid PWM Inverters Using a Low-Computational State Trajectory Prediction Algorithm Incorporating with Reduced-Order Switching Surfaces

This paper introduces a state trajectory prediction algorithm for H-bridge inverters using hybrid pulse-width modulation (h-PWM), which combines unipolar and bipolar switching schemes. By employing reduced switching surfaces, the proposed algorithm can predict the state trajectory for an entire switching cycle, enabling fast control and response. By sampling the state variable at the start of each switching cycle, the duty cycles of all switching devices can be established, and the operating frequency is twice the switching frequency, allowing to reduce the output filter component values and increase the power density. The algorithm has been tested on a 1 kVA prototype inverter, demonstrating its operating principles. The experimental results are in close agreement with the theoretical predictions.