1.State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources (North China Electric Power University) Beijing 102206 China; 2.State Key Lab of Control and Simulation of Power Systems and Generation Equipments (Tsinghua University) Beijing 100084 China; 3.Beijing Sifang Automation Co.,Ltd. Beijing 100085 China
Abstract：Traditional control strategies of high voltage direct current transmission based on modular multilevel converter (MMC-HVDC) have many shortcomings such as complicated control structures,the requirement of multiple PI regulators,rotating coordinate transformation and phase locked loop,and slow dynamic response under unbalanced grid voltage,etc.On the basis of the generalized power model of MMC-HVDC,the deadbeat direct power control method under unbalanced grid voltages is presented,which omits current inner loop so that the complicated reference current computation and multiple PI regulators and the tuning of their corresponding multiple parameters are avoided.This method can regulate active power and reactive power directly and has a fast dynamic response.The power compensation strategy is proposed to achieve three selective control objectives under unbalanced grid voltages,i.e.negative sequence current suppression,active power fluctuation suppression,and reactive power fluctuation suppression,respectively.The computation formulas of the power compensation components for three control objectives are given in this paper.The simulation platform of MMC-HVDC with 11 levels is built in PSCAD/EMTDC,and the simulation results verify the correctness and the effectiveness of the proposed method.
梁营玉, 杨奇逊, 刘建政, 张 涛,. 电网电压不平衡时MMC-HVDC的无差拍直接功率控制[J]. 电工技术学报, 2015, 30(15): 15-25.
Liang Yingyu,Yang Qixun,Liu Jianzheng,Zhang Tao. Deadbeat Direct Power Control for MMC-HVDC Under Unbalanced Grid Voltages. Transactions of China Electrotechnical Society, 2015, 30(15): 15-25.
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2015, Vol. 30 
