A unified voltage quality conditioner for wind power generation

Renewable energy technology has great potential for generating power at a profitable level that concurrently befriends the environment. However, some technologies come with negative factors that limit its market penetration. For wind power, the quality of the generated power limits its extensive use. The main concern for the quality of wind power installations is the fluctuation of voltage levels, which can be attributed to transient states where of the wind turbine generators are first connected to the grid, steady-state levels attributed to the inherent nature of injecting power to the grid, momentary disruptions due to wind gusts and general wind speed variations. This paper adopts the one cycle control (OCC) method in a series connection topology, which here acts as a unified voltage quality conditioner (UVQC), to deal with most of the problems identified above. The new OCC-UVQC has many advantages including no reference calculation resulting in great simplicity, fast transient response, high precision, and a constant switching frequency. The principle of the proposed UVQC is provided in detail. The performance of the voltage quality improvement to the wind turbine is verified to be excellent with the provided experimental waveforms.