Synthesized Power And Frequency Control Method Of Wind Power Generation System Assisted Through Battery Energy Storage System

In recent years, renewable energy has become the focus of attention of the world’senergy workers, as the country’s renewable energy generation attaches great importance toChina’s wind power has become an important emerging industries optimize the energystructure and to promote sustainable development. But with the large-scale wind powerparalleling in the grid, the security, reliability, power quality and grid scheduling of powersystem will be subject to the effects of the fluctuation and randomness of wind powergeneration. Wind farms equipped with energy storage power station connected to the gridto improve the reliability of distribution power networks can reduce the grid frequencyfluctuations in the grid to reduce active power loss, allowing the safe and stable operationof the power system. Finally, establishing equivalent model of the system in the MATLAB/SIMALINK, exert control algorithm on it. Simulation results show that this controlstrategy achieves good security and economy, and gets the desired results.First, research the dynamic equivalent model of the wind farm. The main modeling isrotor excitation converter. Network-side converter adopts the grid voltage oriented vectorcontrol; rotor-side converter adopts the stator flux oriented vector control. So as to achievepower decoupling control of wind power systems.Secondly, establish the model of energy storage converter system according to thecharacteristics of vanadium redox flow batteries. According to the characteristics of windpower fluctuations and control objectives proposed power fluctuations control strategieswill order low-pass filter with a time constant variable combination. Study the principle ofthe storage systems participating in grid frequency regulation, using segmented frequencycontrol strategy to stabilize the frequency fluctuations.Again, make the wind power smoothing and minimum frequency fluctuation as theresearch objectives, proposed a method to consider adding SOC (state of charge) low-passfiltering principle of variable time constant feedback to smooth the power and control of the use of sub-combination of multi-frequency deviation target control methods. Establishthe model of wind power systems and energy storage systems in MATLAB, the windpower storage system can be required to smooth the output power, and participate in thecontrol grid frequency as same as the conventional generator. Simulation results show thatthis control strategy has good security and economy, and achieved good economic andsocial benefits.