计及边带分量频率耦合的电压源型换流器输入导纳建模  

Voltage Source Converter Input Admittance Model Considering Frequency Coupling of Sideband Components

作　　者：徐少博 徐永海[1] 陶顺[1] 王莹鑫 张华赢 Xu Shaobo;Xu Yonghai;Tao Shun;Wang Yingxin;Zhang Huaying(School of Electrical and Electronic Engineering North China Electric Power University,Beijing 102206 China;New Smart City High-Quality Power Supply Joint Laboratory of China Southern Power Grid Shenzhen Power Supply Co.Ltd,Shenzhen 518020 China)

机构地区：[1]华北电力大学电气与电子工程学院,北京102206 [2]南方电网公司新型智慧城市高品质供电联合实验室(深圳供电局有限公司),深圳518020

出　　处：《电工技术学报》2023年第11期2883-2893,共11页Transactions of China Electrotechnical Society

基　　金：南方电网公司科技资助项目(090000KK52220014/SZKJXM20220021)。

摘　　要：在高比例可再生能源和高比例电力电子设备接入背景下,配电网中的谐波污染和耦合谐振特性逐渐向高频段扩展。高频谐振特性分析时,现有基于开关周期平均的电压源型变换器(VSC)单频阻抗模型难以满足奈奎斯特频率以上的阻抗建模精度需求。为此,该文分析了VSC控制器采样和脉冲宽度调制(PWM)环节产生的边带分量与扰动量之间的频率耦合机理;同时考虑两类边带分量的频率耦合,建立了适用于奈奎斯特频率以上的VSC多频耦合输入导纳模型;分析了PWM采样方式、抗混叠滤波器截止频率对VSC输入导纳的影响规律。基于硬件在环仿真平台的频率扫描和稳定性分析结果,验证了计及边带分量频率耦合的VSC输入导纳模型和相关理论分析的准确性。Under the background of high proportion of renewable energy and high proportion of power electronic equipment access,the harmonic pollution and coupling resonance characteristics in the distribution grid gradually expand to the high frequency band.The controller sampling process and pulse width modulation(PWM)process of voltage source converter(VSC)have sideband effect.When the frequency of the disturbance signal exceeds the Nyquist frequency,the amplitude of the sampling and PWM sideband components will be higher than the original disturbance due to the influence of spectrum aliasing and the low-pass filtering characteristics of the controller,resulting in an obvious frequency coupling effect between the sideband components and the disturbance,thus affecting the VSC input admittance characteristics.In the analysis of high-frequency resonant characteristics,the existing single frequency impedance model of VSC based on switching cycle averaging is difficult to meet the impedance modeling accuracy requirements above Nyquist frequency.Therefore,this paper analyzes the frequency coupling mechanism between the sideband component and disturbance generated by VSC controller sampling and PWM link;Considering the frequency coupling of two kinds of sideband components,the VSC multi-frequency coupling input admittance model above Nyquist frequency is established.Firstly,the generation mechanism of VSC sampling sideband component and PWM sideband component and the frequency coupling mechanism with disturbance are analyzed.Under the action of sideband effect,sampling sideband component,PWM sideband component and disturbance signal realize frequency coupling through feedback loop between VSC control system and physical circuit,thus affecting VSC port impedance characteristics.Considering the suppression effect of ZOH and filter on high frequency components in the sideband,the model can only retainωs-ωp andωc-ωp-ω0 sideband component.Considering the influence of current inner loop control,system voltage feedforward control

关 键 词：电压源型变换器 采样 脉冲宽度调制 边带分量 输入导纳 

分 类 号：TM464[电气工程—电器]