【摘要】 主要研究飞轮储能系统放电过程的直流母线电压稳定控制算法。飞轮放电过程中电机反电势随转速持续下降,直流侧负载通常具有电流突变的脉冲负载特性,而且传统PI双闭环控制的直流母线电压外环控制器具有非线性,导致其应对负载电流突变的动态响应慢,对转速变化的适应性差。为解决上述问题,本文提出了一种采用负载电流和转速补偿的飞轮储能系统放电控制算法。该方法将直流侧负载电流和电机转速信号补偿至直流母线电压外环,根据双向能量变换器交直流侧的功率平衡关系,对传统PI控制器的输出进行修正,重新计算q轴有功电流的给定值。此外,针对飞轮储能系统采用的高速电机d、q轴耦合电压大的特点,本文在电流内环也增加了前馈解耦算法,以实现d、q轴电流的独立解耦控制,增强对电流给定信号的跟踪能力。仿真和实验结果与理论分析一致,证明了改进后的放电算法具有更快的动态响应速度和更强的转速适应能力。更多还原

【Abstract】 This paper mainly researches the DC bus voltage control strategy during the discharge period of Flywheel Energy Storage System(FESS). Focused on the DC bus fluctuation caused by wide speed range and pulsed load current of FESS, an improved discharge control strategy with load current and rotor speed compensation is proposed to enhance the system adaption to speed variation and accelerate the voltage response at abrupt load change. The load current and rotor speed is compensated to the nonlinear outer DC bus voltage loop, and the reference value of q-axis current is recalculated according to the power balance between AC and DC side of the bidirectional converter. Feedforward decoupling strategy is also utilized in the inner current loop to realize the independent control of the d-axis and q-axis currents. Simulation results and experiment results are in reasonable agreement with the theory analysis, which verify the effectiveness and improvement of the proposed strategy.更多还原