Digital control of a power inverter

This work reports on the design of a digital feedback control system for a power inverter. The proposed controller achieves asymptotic output tracking of reference sinusoidal voltages with known frequency and achieves asymptotic rejection of sudden load variations; moreover, the obtained control system is robust with respect to uncertainties in the DC input voltage. Thus, on one hand the compensator here presented represents an improvement with respect to existing sliding-mode designs since it does not show the undesirable chattering phenomenon; on the other hand, the obtained controller is less sensitive to variations of load and DC input voltage compared to previous digital dead-beat controllers for power inverters. The design was tested by means of a 400 Hz demonstrator, revealing quite interesting performance both in steady-state and transient operation.