超级电容器在配电网供电可靠性中的仿真分析

Simulation Analysis of Super Capacitor in Power Supply Reliability of Distribution Network

针对配电网中由于不确定性负荷导致的电压突变、功率波动等问题,文中研究了超级电容器在配电网供电可靠性中的应用。基于超级电容器充放电特性,构建了由超级电容器组、DC/DC变流器以及电网换流器组成的超级电容器储能系统。为了实现超级电容器和配电网的功率交换,研究了基于电感电流内环控制,电容电压外环控制的DC-DC变流器电流双向控制策略。针对DC/AC换流器,采用指定功率的方法,利用外环控制器实现功率的交换和跟踪,通过内环控制器实现对电网扰动电压的前馈补偿。在此基础上,通过引入d轴和q轴电压的补偿项,实现对电流的解耦控制。基于文中所述的控制策略,仿真结果表明,超级电容器具有一定的无功补偿和有功补偿能力,能够抑制电压波动,保证系统供电的稳定性和可靠性。

In view of such problem as voltage mutation and power fluctuation due to uncertain load in distribution network,the application of super⁃capacitors in power supply reliability of distribution network is studied in this paper.The energy storage system of super⁃capacitor consisting of super⁃capacitor banks,DC/DC inverter and grid converters is constructed on the basis of the charging and discharging characteristics of super⁃capacitor.For achieving power exchange between super⁃capacitor and distribution network,the current bidirectional control strategy of DC-DC converter based on inductance current inner loop control and capacitance voltage outer loop control is studied.For DC/AC converter,the method of specified power is adopted.The power switching and tracking is achieved by the outer loop controller and feed⁃forward compensation of disturbance voltage in power grid by the inner loop controller.On this basis,the decoupling control of current is achieved by introducing compensation terms of d⁃axis and q⁃axis voltage.It is shown by the simulation result based on the control strategy in this paper,that the super⁃capacitor has a certain ability of reactive power compensation and active power compensation,can restrain voltage fluctuation and ensure the stability and reliability of power supply.