基于无源阻尼改进的并网逆变器电压背景谐波抑制策略  

Control Strategy of Grid-connected Inverter Suppressing Grid-voltage Background Harmonics Based on the Improved Passive Damping Method

作　　者：廖志凌[1] 徐东[1] 崔晓晨[1] 梅从立[1] 刘国海[1] 

机构地区：[1]江苏大学电气信息工程学院,江苏镇江212013

出　　处：《电测与仪表》2013年第1期21-26,37,共7页Electrical Measurement & Instrumentation

基　　金：中国博士后基金资助项目(2012M521009);江苏省高校自然科学研究项目(11KJB470005);江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：针对LCL型三阶滤波结构的并网逆变器运行时易发生谐振,且当电网电压存在背景谐波的情况下易受畸变电压影响的问题,从无源阻尼方式入手分析了电网电压背景谐波对逆变器工作性能及并网电流波形质量的影响,推导了LCL型并网逆变器抑制电网电压背景谐波的前馈电压函数,在此基础上将原系统的无源电阻虚拟化,解决了无源阻尼的损耗和散热问题,进而实现系统稳定运行的有源阻尼的谐振抑制方法,通过对单相无变压器Heric结构并网逆变器的仿真实验研究,验证了理论分析的正确性。The traditional LCL-fiher grid-connected inverter is a third-order system without damping that may cause the resonance phenomenon. Also, it will be affected by the distorted grid-voltage background harmonics. In order to over- come these problems, based on the passive damping method, a new control strategy is proposed. The paper analyzed the current waveform performance of grid-connected inverter in the condition of grid-voltage background harmonics, then derived the feed-forward function for grid-connected inverter. The disadvantages of passive damping could be well solved by virtualizing damping resistor of the original system, which realized the active damping suppression of reso- nance. Simulation results based on the Heric single-phase transformerless grid-connected inverter verify the correct- ness of the theoretical analysis.

关 键 词：电压背景谐波 单相并网逆变器 无源阻尼 虚拟化 LCL-滤波器 

分 类 号：TM46[电气工程—电器]