Parameters self-adjusting fuzzy PI control with repetitive control algorithms for 50 Hz on-line UPS controlled by DSP

In this paper a hybrid parameters self-adjusting fuzzy PI with repetitive control algorithms is proposed for single-phase UPS cost effective waveform control. The control structure, the important control parameters, and the system software design are described in detail. A 50 Hz 1 kVA prototype is constructed. The core chip is TMS320F240, Experimental results prove that the proposed control scheme not only can stabilize the output sine wave of the inverter but also produce fast transient response subject to load step change.