一种基于电容电流反馈的有源阻尼补偿方法  

Study on an Active Damping Compensation Method Based on Capacitive Current Feedback

作　　者：薛荣辉 Xue Ronghui(School of Electronic Engineering,Xi'an Aeronautical Institute,Xi'an 710077)

机构地区：[1]西安航空学院电子工程学院,陕西西安710077

出　　处：《中阿科技论坛（中英文）》2024年第12期85-89,共5页China-Arab States Science and Technology Forum

基　　金：西安航空学院校级项目(2020KY1225)。

摘　　要：随着全球对清洁能源的需求不断增长,各类发电设备对并网的要求越来越高。在弱电网环境下,线路阻抗的变化会引起谐振频率的偏移,该现象已经被广泛研究和探讨。并网逆变器采用LCL滤波器滤波时,存在谐振尖峰问题,通常采用电容电流有源阻尼控制。然而,由于电网阻抗的影响,控制效果不佳,并网电流不能满足并网要求。文章通过研究数字控制带来的延时对有源阻尼效果的影响,发现系统稳定性和鲁棒性会受到威胁。针对数字控制延时带来的不利影响,结合电网阻抗的影响,提出了一种基于弱电网的改进型电容电流反馈有源阻尼方法。该方法通过在电容电流有源阻尼反馈环路中增加延迟反馈环节,将系统的有效阻尼区从(0, fs/6)扩展到(0,fs/4)。同时,文章建立了连续系统和离散系统模型,并结合数字控制设计了系统参数。仿真验证结果显示,所提方法能够达到稳定性和鲁棒性的要求。As the global demand for clean energy continues to grow,power generation equipment demands increasingly high requirements for grid connection.Under the weak grid environment,changes in line impedance can cause a shift in resonant frequency,which has been widely studied.When LCL filters are used for grid-tie inverters,resonance spikes are induced,which can be controlled by current active damping.However,due to the influence of grid impedance,the control effect is unsatisfactory,making grid-connected current unable to meet the requirements.In view of this,the article finds that system stability and robustness are threatened by the impact of delay caused by digital control on the active damping effect.Aiming at the adverse effects of delay,an improved capacitive current feedback active damping method based on weak grid is proposed.This method extends the effective damping region from(0,fs/6)to(0,fs/4)by adding a delay feedback.At the same time,continuous and discrete systems are also modeled,and parameters are set according to digital control.The simulation verification results show that the proposed method can meet the requirements of stability and robustness.

关 键 词：LCL滤波器 电容电流 有源阻尼 数字控制延时 

分 类 号：TM50[电气工程—电器]