一种扩展LCL型并网逆变器有效阻尼区的超前补偿方法  

Lead compensation method for extending valid damping region ofLCL-type grid-connected inverter

作　　者：华铤 林桦[1] 肖建杰 王兴伟[1] HUA Ting;LIN Hua;XIAO Jianjie;WANG Xingwei(Key Laboratory of Power Electronics and Energy Management,Ministry of Education,School of Electrical and Electronic Engineering,Huazhong University of Science&Technology,Wuhan 430074,China)

机构地区：[1]华中科技大学电气与电子工程学院电力电子与能量管理教育部重点实验室,湖北武汉430074

出　　处：《电力自动化设备》2020年第9期197-202,共6页Electric Power Automation Equipment

摘　　要：考虑数字控制延迟,LCL型并网逆变器系统的有效阻尼区仅在采样频率fs的1/6以内,较窄的阻尼区间使得系统的稳定区域很小,不利于系统参数的设计。针对此问题,提出一种在阻尼环路中加入超前补偿控制器的改进方法。首先,通过分析系统的有源阻尼特性,得出加入超前补偿后系统的有效阻尼区可以扩展到(0,fR),其中fR∈(fs/6,fs/3)。接着分析了加入超前补偿后被控对象的稳定性,给出临界电容电流反馈系数与超前补偿参数之间的关系。为了扩大原系统的稳定区域,提出了一套超前补偿控制器的参数设计方法。最后通过实验进行验证,实验结果验证了所提方法的有效性。Considering the digital control delay,the valid damping region of LCL-type grid-connected inverter system is only within 1/6 sampling frequency(fs/6).The narrow damping region results in the small stability region of system,which is not conducive to the design of system parameters.To solve this problem,an improved method of adding a lead compensator in the damping loop is proposed.Firstly,by analyzing the active damping characteristics of system,it is concluded that the effective damping region of system after adding lead compensation can be extended to(0,fR),where fR∈(fs/6,fs/3).Then,the stability of the con⁃trolled object after adding lead compensation is analyzed,and the relationship between the critical capacitor current feedback coefficient and the parameters of lead compensation is given.In order to extend the sta⁃bility region of the original system,a set of parameter design method of the lead compensator is proposed.Finally,the experimental results verify the effectiveness of the proposed method.

关 键 词：LCL型并网逆变器 电容电流反馈 控制延迟 有效阻尼区 稳定区域 补偿 

分 类 号：TM464[电气工程—电器]