海上风场混合直流送出系统停机策略研究  

Shutdown Strategy for Hybrid DC Transmission System in Offshore Wind Farm

作　　者：方陈 魏新迟 时珊珊 杨建平 蔡旭[2] 方梓熙 FANG Chen;WEI Xinchi;SHI Shanshan;YANG Jianpin;CAI Xu;FANG Zixi(State Grid Shanghai Municipal Electric Power Company,Shanghai 200120,China;Key Laboratory of Control of Power Transmission and Conversion(Ministry of Education),Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]国网上海市电力公司,上海200120 [2]上海交通大学电力传输与功率变换控制教育部重点实验室,上海200240

出　　处：《电源学报》2024年第2期263-272,共10页Journal of Power Supply

基　　金：国家电网公司总部科技资助项目(520940200010)。

摘　　要：对基于二极管整流器的低成本混合直流换流器的停机策略进行了研究。将辅助换流器的停机过程分为能量回馈与能量耗散阶段,能量回馈阶段通过主动控制,将子模块电容上储存的部分能量经直流母线回馈到电网中;能量耗散阶段通过耗散电阻依次对谐振电容和子模块电容放电,并推导了放电电流、电容电压和放电时间的计算方法,给出了耗散电阻的设计方法。所提停机策略能够快速有效实现换流器电容放电,且不需要高耐压大容量的耗散电阻,有利于工程实现。最后在Matlab/Simulink中搭建了相应的仿真模型,仿真结果验证了停机策略的有效性。A shutdown strategy for a low-cost hybrid DC converter based on diode rectifier is studied.The shutdown process of the auxiliary converter is divided into an energy feedback stage and an energy dissipation stage.At the energy feedback stage,part of the energy stored in the capacitors of sub-modules is fed back to grid through the DC transmission line under the active control.At the energy dissipation stage,the resonant capacitor and the capacitors of sub-modules are discharged in sequence through a discharging resistor.The calculation methods for the discharging current,capacitance voltage,and discharging time are derived,and the design method for the discharging resistor is also given.The capacitors of the auxiliary converter can be discharged quickly and efficiently under the proposed shutdown strategy without a high-voltage and large-capacity discharging resistor,which is conducive to the realization in engineering projects.Finally,a simulation model is constructed in Matlab/Simulink,and the validity of the shutdown strategy is verified by simulation results.

关 键 词：二极管整流器 混合直流换流器 放电过程 停机策略 柔性直流输电 

分 类 号：TM933[电气工程—电力电子与电力传动]