谐波扰动下PWM边带谐波特性分析  

Analysis of PWM sideband harmonic characteristics with harmonic disturbance

作　　者：徐少博 徐永海 陶顺 周胜军 周文 苏灿 XU Shaobo;XU Yonghai;TAO Shun;ZHOU Shengjun;ZHOU Wen;SU Can(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University),Bejing 102206,China;State Grid Smart Grid Research Institute Co.,Ltd.,Beijing 10221l,China;State Grid Hebei Electric Power Research Institute,Shijiazhuang 050021,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京102206 [2]国网智能电网研究院有限公司,北京102211 [3]国网河北省电力有限公司电力科学研究院,石家庄050021

出　　处：《电测与仪表》2024年第9期172-181,共10页Electrical Measurement & Instrumentation

基　　金：国家电网有限公司科技项目(5400-202258419A-2-0-ZN)。

摘　　要：配电网背景谐波以及系统中并联运行的电力电子设备开关次谐波等宽频带谐波分量,可经电压、电流采样后进入电力电子变换器控制系统,并传递至脉冲宽度调制(pulse width modulation,PWM)环节。在边带效应作用下,PWM输出量中将产生一系列与扰动谐波频率相关的次生边带谐波,加剧电力电子变换器输出波形的谐波畸变,已成为电力电子化配电网谐波污染的重要来源之一。为此,针对五种典型PWM调制方式,分别建立了考虑谐波扰动影响的PWM边带谐波分析模型;提出了适用于谐波扰动影响下PWM谐波性能分析的改进总谐波畸变率(total harmonic distortion,THD)评价指标;最后,基于数学模型与所提ITHD指标,分析了采样方式、载波形式以及扰动谐波幅值等因素对谐波扰动下PWM输出波形中边带谐波发射特性的影响规律。The broadband harmonic components such as background harmonics of the distribution network and the switching harmonics from the power electronic equipments operating in parallel can inject into the power electronic converter control system by voltage and current sampling.These harmonics can be transmitted to the pulse width modulation(PWM) stage.Under the influence of the sideband effects,a series of secondary sideband harmonics related to disturbance harmonic frequency will be generated in the PWM output waveforms,which exacerbate the harmonic distortion of power electronic converters and become important sources of harmonic pollution in power electronic distribution networks.Therefore,PWM sideband harmonic analysis models considering the influence of wideband background harmonic disturbance are established for five typical PWM modulation methods and simulated for verification.An improved total harmonic distortion(ITHD) evaluation index suitable for PWM harmonic performance analysis under broadband background disturbances is proposed.Finally,based on the mathematical model and the proposed ITHD index,the influence law of sampling methods,carrier forms and amplitude of background harmonic on the sideband harmonic emission characteristics is analyzed.

关 键 词：脉冲宽度调制 谐波扰动 采样方式 载波形式 边带谐波特性 改进总谐波畸变率 

分 类 号：TM93[电气工程—电力电子与电力传动]