High-performance cascade-type repetitive controller for CVCF PWM inverter: analysis and design

A novel cascade-type repetitive controller with phase-cancellation filter is proposed for a constant-voltage constant-frequency pulse-width-modulated DC-AC converter to achieve very low total harmonic distortion and fast transient response. The paper reveals the principle of phase cancellation for the performance improvement of RC. In the form of real-time window filtering, a phase-cancellation filter is developed for the repetitive controller. Experimental results show that a high-quality AC source can be achieved by the proposed scheme even under nonlinear rectifier load and parameter uncertainties.