摘要
针对模块化多电平换流器在预充电过程中,子模块电容电压均压效果劣化问题,基于换流器不控整流充电过程中子模块电容电压的均衡特性,建立了包含子模块取能电源等效阻抗、阀塔寄生电容和水路电阻的子模块级精细化阀塔仿真模型。计算了不同参数下子模块的不均压度,分析了取能电源功率分散性、均压电阻精度、水路电导率对子模块均压效果的影响机理。研究发现,子模块的参数差异性导致的充电电流不同和阀塔寄生参数导致的对地电流,是造成预充电时子模块均压效果劣化的主要因素,均压电阻可为电荷提供泄放路径,使得电荷从电压较高的子模块向电压较低的子模块转移,有助于平衡各子模块的电容电压。研究成果可为模块化多电平换流器子模块均压电阻的运行工况、性能指标优化设计研究提供理论基础。
As for the voltage grading effect deterioration of submodule capacitor during the pre-charging process of the modular multilevel converter,a submodule-level refined valve tower simulation model,including the equivalent impedance of submodule absorption power supply,parasitic capacitance of valve tower and water resistance,is set up based on the grading characteristics of capacitive voltage of the submodule during the charging process of convert-er uncontrolled rectifier.The unevenness of submodules under different parameters is calculated,and the influence mechanism of energy obsorption power supply deviation,accuracy of grading resistor and water conductivity on the grading effect of sub-modules is analyzed.It is found by the research that the different charging currents due to the differences in submodule parameters,and the current to earth due to the parasitic parameters of the valve tower are the main factors that cause the deterioration of the grading effect of the submodule during pre-charging period.The grading resistor can provide a discharge path for the charge so that the charge is transferred from the sub-module with higher voltage to that with lower voltage,which helps to balance the capacitive voltage of each submodule.The re-search results can provide a theoretical basis for optimizing the operating condition and performance index of the gra-dign resistor of the modular multilevel converter.
作者
王振
郑润民
肖凯
许琳浩
蔡志宏
牛戈钊
张梦楠
刘梦琦
刘琦
徐海博
WANG Zhen;ZHENG Runmin;XIAO Kai;XU Linhao;CAI Zhihong;NIU Gezhao;ZHANG Mengnan;LIU Mengqi;LIU Qi;XU Haibo(CSG EHV Electric Power Research Institute,Guangzhou 510620,China;Xi’an XD Power System Co.,Ltd.,Xi’an 710065,China)
出处
《高压电器》
北大核心
2025年第8期176-185,共10页
High Voltage Apparatus
基金
中国南方电网有限责任公司科技项目(CGYKJXM20220356)。
关键词
模块化多电平换流器
不控整流充电
子模块均压劣化
阀塔寄生参数
子模块等效阻抗
均压电阻
modular multilevel converter
uncontrolled rectifier charging
grading deterioration of submodule
valve tower parasitic parameter
equivalent impedance of submodule
grading resistance
