Research On Active Power Online Optimal Control for Hydrostatic Transmission Wind Turbine

Abstract

Wind has been admitted as one of the most promising renewable energy resources in multinational regionalization policies. However, due to the randomness and volatility of wind energy and the rigid transmission of traditional wind turbines, it is difficult to control the active power of wind turbines with high precision. Thus the hydraulic wind turbines (HWT) is taken as the research object, and the stable operation of wind turbines at a demand power point under certain wind speed conditions is realized. The mathematical model of HWTs is established, and the HWT operation characteristics are analyzed. The small signal linearization method is adopted to solve the multiplying nonlinear problems in the system, and the working area of the power transmission system to adjust the transmission power stably is analyzed. According to the demand of active power control for wind turbine, the HWT active power control strategy is proposed. However, the power response of the HWT is inconsistent with the time-varying operating point and the proposed controller fixed parameters. The controller parameter online adjustment method of system pressure and power gain is proposed. The effectiveness of the optimized control method is verified based on the semi-physical simulation experiment platform of HWT, and the consistency of active power response is achieved. At the same time, the power response characteristics are analyzed, and the HWT active power response time can satisfy the demand of electrical grid under the optimal control strategy.

Keywords

• Wind power generation
• hydraulic systems
• power control
• control nonlinearities
• optimal control