Progressively converging deadbeat control for UPS inverter

Deadbeat control for UPS inverters has essential stability problem and robustness problem. A novel deadbeat control method, progressively converging deadbeat control (PCD), is proposed to solve the problems. Instead of sinusoidal reference signal, weighted average of the reference and current output voltage is chosen to be the target value of next sampling instant. Adjusting the weighing makes tradeoff between stability and rapidity. Static error, stability and dynamic response are analyzed using discrete transfer function. A 1 kVA prototype was built up based on DSP. Theoretical analysis and experimental results show that PCD control has good stability, small static error and fast dynamic response and the robustness is better than conventional deadbeat control.