模块化多电平HVDC输电系统子模块电容值的选取和计算  

Selection and Calculation for Sub-module Capacitance in Modular Multi-level Converter HVDC Power Transmission System

作　　者：王姗姗[1] 周孝信[1] 汤广福[1] 贺之渊[1] 滕乐天[2] 刘隽[2] 

机构地区：[1]中国电力科学研究院,北京市海淀区100192 [2]上海市电力公司,上海市浦东区200122

出　　处：《电网技术》2011年第1期26-32,共7页Power System Technology

基　　金：国家自然科学基金项目(50777058)~~

摘　　要：从模块化多电平柔性直流输电系统稳态能量交换过程、有功功率控制动态响应特性、暂态能量交换过程及直流双极短路故障时桥臂保护要求4个方面分析了子模块电容值与直流系统运行特性之间的数学关系。根据理论分析结果,给出了模块化多电平子模块电容的选取原则和计算方法。通常根据稳态子模块电压波动和有功功率控制动态响应特性的要求计算子模块电容值,再根据暂态子模块电压波动和桥臂保护的要求进行校验。利用PSCAD电磁暂态仿真模型对设计实例进行了仿真分析,结果表明该设计方法是合理、可行的。The mathematical relation between the value of sub-module capacitance and operational characteristics of HVDC system is analyzed in four aspects, i.e., the steady-state energy conversion process, dynamic response process of active power control and transient energy conversion process in modular multi-level converter HVDC power transmission system as well as the requirement to bridge arm protection during bipolar short-circuit fault, is researched. Based on the result of theoretical analysis, the principle and calculation method for the selection of modular multi-level sub-module capacitance are given. Usually, the value of the sub-module capacitance is calculated according to the voltage fluctuation and the requirement to dynamic response characteristic of active power control, and the calculation result is verified by transient voltage fluctuation of sub-model and the requirement to the bridge arm protection. Utilizing the model based on electromagnetic transient simulation sottware PSCAD, a practical design case is simulated, and simulation results show that the proposed selection principle and calculation method are reasonable and feasible.

关 键 词：电压源换流器 高压直流输电 模块化多电平换流器 子模块电容值 参数设计 

分 类 号：TM72[电气工程—电力系统及自动化]