Participation of Doubly Fed Induction Generator Based Wind Turbine in Frequency Regulation with Frequency-linked Pricing

Abstract

The increasing share of wind power in the generation mix may lead to serious threats to system frequency, as the wind unit does not provide inertia and isolates from the grid during disturbances. The adverse effects of disturbances can be mitigated if wind units also contribute to system inertia. This article analyzes the dynamic participation of a doubly fed induction generator based wind turbine in system frequency regulation. The modified inertial control scheme is proposed for a doubly fed induction generator that uses frequency deviations, instead of derivative of frequency, to provide fast active power injection, which arrests the fall in frequency during transient conditions. To enhance the participation of a doubly fed induction generator in frequency control, optimal values of the speed control parameters of a doubly fed induction generator based wind turbine have been obtained using the integral square error technique. Frequency-linked pricing control is used to provide secondary frequency control to reset the frequency close to its nominal value. The simulation studies have been conducted in a two-area interconnected power system to demonstrate the contribution of the doubly fed induction generator and frequency-linked pricing control in system frequency regulation.

Keywords:

• doubly fed induction generator
• frequency regulation
• frequency-linked pricing
• availability-based tariff