基于STATCOM-BESS的风电场功率协调控制策略研究

Research on Coordinated Control Strategy of STATCOM-BESS in Wind Farm

为有效地提高风电场并网运行能力,改善传统静止无功发生器只能补偿无功功率而且会消耗一定有功功率的不足,将静止无功发生器与蓄电池储能系统相结合作为整体补偿装置用于风电并网系统进行研究,并提出一种功率协调控制策略对有功无功功率进行协调控制。首先介绍了STATCOM-BESS工作原理并建立整体数学模型,采用旋转坐标系解耦控制方法实现了电流解耦。然后在Matlab/Simulink中搭建风力发电系统仿真模型进行仿真,仿真结果表明装置具有快速功率调节能力,在风速渐变、电网扰动和频率波动情况下对风电场都具有较好的动态支撑能力,因此验证了理论分析的正确性和所提出的控制方法的有效性。

To effectively improve grid-connected operation ability of wind farm, battery energy storage system （BESS） is proposed to combine with the static synchronous compensator （STATCOM）, which worked as a compensation device that just only can regulate the reactive power and absorb active power, to achieve the power dual regulation. At first, the operating principle of STATCOM-BESS is described and a mathematical model is derived. Then the current decoupling control method is adopted to realize the independent regulation of active and reactive power, the coordinated control strategy of STATCOM-BESS is proposed in the operation of wind farm at the same time. At last, the model of wind farms with STATCOM-BESS is established in Matlab/Simulink. The simulation resuits show that the proposed model can precisely and quickly control both active and reactive power, and has excellent dynamic state characteristics under the wind speed gradient, power grid voltage and frequency disturbance cases, which verify the validity of the theoretical analysis and the effectiveness of the proposed control strategy.