A DSP control system for the grid-connected inverter in wind energy conversion system

The development of power electronics leads to the idea of variable-speed direct-drive generators in the field of wind energy conversion system. This paper discusses the PWM converter used as the grid-connected inverter in the variable-speed direct-drive conversion system. The grid-connected inverter has to be controlled to maintain constant DC link voltage and to keep sinusoidal AC current at unity power factor. This paper introduces the principle of PWM converter whose DC voltage and AC current are controlled by the SICT control strategy which can obtain the bi-direction high dynamic features at a fixed switching frequency. The hardware and software of the DSP control system of the grid-connected inverter are presented subsequently. Experimental results show that the AC currents are close to sinusoidal being in-phase with the AC voltage and DC voltage can be maintained constant.