白鹤滩-江苏特高压混合级联直流系统运行特性分析方法  

Operation characteristic analysis method of Baihetan-Jiangsu hybrid cascaded UHVDC system

作　　者：董芷函 王国腾 徐政[1] 李建华 丁浩寅 DONG Zhihan;WANG Guoteng;XU Zheng;LI Jianhua;DING Haoyin(College of Electrical Engineering,Zhejiang University,Hangzhou 310027,China;State Grid East China Electric Power Control Center,Shanghai 200120,China)

机构地区：[1]浙江大学电气工程学院,浙江杭州310027 [2]国家电网华东电力调控中心,上海200120

出　　处：《电力自动化设备》2022年第6期118-125,共8页Electric Power Automation Equipment

基　　金：国家电网华东分部科技项目(SGHD0000DKJS2000087)。

摘　　要：白鹤滩—江苏特高压混合级联直流系统逆变侧由电网换相换流器(LCC)和模块化多电平换流器(MMC)串联组成。为保证混合级联直流系统投运后安全稳定运行,从混合级联直流系统稳态响应特性、逆变侧LCC换流母线电压稳定性、MMC暂时过电压估算以及逆变站出线热稳裕度计算4个方面出发,提出了一种混合级联直流系统运行特性分析方法。仿真结果表明,所提方法可以快速、准确分析混合级联直流系统运行特性,定位系统运行薄弱环节。根据分析结果:部分工况下白鹤滩—江苏特高压混合级联直流系统的稳态响应特性较差,功率传输能力降低;交流短路故障下,MMC存在暂时过电压问题,从而影响白鹤滩—江苏特高压混合级联直流系统的正常运行。The inverter side of Baihetan-Jiangsu hybrid cascaded UHVDC(Ultra High Voltage Direct Current)system is composed of LCC(Line Commutated Converter)and MMC(Modular Multilevel Converter)in series.In order to ensure the safe and stable operation of the hybrid cascaded DC system,an operation characteris-tic analysis method of the hybrid cascaded DC system is proposed from the four aspects of the steady-state response characteristics of the hybrid cascaded DC system,the voltage stability of commutation bus of inverter-side LCC,the estimation of MMC temporary overvoltage,and the thermal stability margin calculation of inverter station outlines.The simulative results show that the proposed method can quickly and accurately analyze the operation characteristics of the hybrid cascaded DC system and locate the weak links of the system.According to the analysis results,the steady-state response characteristics of the Baihetan-Jiangsu hybrid cascaded UHVDC system are poor and the power transmission capacity is reduced under certain operating conditions.Under AC short circuit faults,the MMC has the problem of temporary overvoltage,which affects the normal operation of the Baihetan-Jiangsu hybrid cascaded UHVDC system.

关 键 词：电网换相换流器 模块化多电平换流器 混合级联直流系统 响应特性 暂时过电压 

分 类 号：TM74[电气工程—电力系统及自动化] TM721.1