摘要
基于模块化多电平换流器的多端柔性直流输电系统(modular multilevel converter based multi-terminal DC transmission systems,M M C-M TDC)中传统偏差控制和下垂控制无法实现功率与电压的无静差调节,为使系统达到最优运行状态,提出下垂补偿控制策略。首先对传统控制方式进行分析,充分考虑线路电阻产生的电压降落对传统控制方式的影响;然后针对系统功率偏差产生的电压偏移对下垂曲线电压参考指令进行补偿修正;最后,在PSCAD/EMTDC上搭建五端仿真模型,稳态与暂态2种工况下对比3种控制方式,结果表明系统功率改变后可以消除功率与电压的静态偏差,并且电压不会产生超调,保证系统始终运行在最优状态。
The traditional error control and droop control cannot achieve the floating control of power and voltage in MMC-MTDC （modular multilevel converter based multi-terminal DC transmission systems）. In order to make the system achieve the optimal operating state, this paper proposes the droop compensation control strategy. Firstly, we analyze the traditional control methods with fully considering the voltage drop caused by line impedance in the traditional control mode. Then, we compensate the voltage reference instruction of the droop curve for the voltage offset caused by the power deviation of the system. Finally, we construct a five terminal simulation model on PSCAD/EMTDC, and compare three control methods under the two conditions of steady state and transient state. The results show that the static deviation of power and voltage can be eliminated by changing the power of the system, and the voltage will not overshoot, which can ensure that the system is always running in the optimal state.
作者
董辉
宋平岗
周振邦
DONG Hui SONG Pinggang ZHOU Zhenbang(School of Electrical and Automation Engineering, East China Jiaotong University, Nanchang 330013, China)
出处
《电力建设》
北大核心
2017年第8期80-85,共6页
Electric Power Construction
