一种计及总损耗功率估计与转速前馈补偿的飞轮储能系统放电控制策略

Aiming at the problems that factors such as the rapid decrease in the flywheel speed and the sudden change in the DC side power during the discharge process of the flywheel energy storage system affect the dynamic performance and stability of the bus voltage, based on the traditional flywheel PI discharge control strategy, this paper proposes a discharge control strategy for the flywheel energy storage system that takes into account the total loss power estimation and the speed feed - forward compensation. The capacitive energy storage proportional feedback control is adopted, and a nonlinear disturbance observer is used to uniformly observe the total loss power such as the motor and converter loss power and the load power, and a speed compensation link is introduced to conduct direct feed - forward compensation control on the system; according to the dominant pole diagram and the Bode diagram of the closed - loop control system, the stability and anti - disturbance performance of the system are analyzed, and a method for selecting the controller parameters is given. This control strategy has few adjustment parameters, does not require a current sensor on the load side, and has a simple control structure. The simulation and experimental results show that the proposed discharge control strategy and parameter selection method can effectively suppress the influence of the rapid decrease in the flywheel speed and the sudden change in the DC side load on the bus voltage, and the robustness of the system is improved.

针对飞轮储能系统放电过程中飞轮转速迅速下降、直流侧功率突然变化等因素影响母线电压动态性能和稳定性的问题,该文在传统飞轮PI放电控制策略基础上,提出一种计及总损耗功率估计与转速前馈补偿的飞轮储能系统放电控制策略。采用电容储能比例反馈控制,利用非线性扰动观测器对电机与变流器损耗功率、负载功率等总损耗功率进行统一观测,并引入转速补偿环节对系统进行直接前馈补偿控制;根据闭环控制系统的主导极点图和伯德图,分析系统的稳定性与抗扰动性能,并给出一种控制器参数的选择方法。该控制策略调节参数少、无需负载侧的电流传感器、控制结构简单。仿真和实验结果表明,所提放电控制策略和参数选择方法能够有效抑制飞轮转速迅速下降和直流侧负载突变对母线电压的影响,系统鲁棒性得到提高。