摘要
在LCL型并网逆变器的稳定控制中,电容电流反馈有源阻尼方法由于谐振抑制效果优良而受到广泛应用,但该方法的阻尼效果易受控制延时的影响,导致等效虚拟电阻的正负性会随着频率的增大而发生转变,而负阻性的虚拟电阻可能会使并网逆变器在电网阻抗变化的工况环境下产生不稳定现象。为解决该问题,提出了一种基于二阶广义积分器(SOGI)的延时补偿方法,可显著扩大等效虚拟电阻的正负分界频率,之后对采用补偿方法后的系统性能进行了详细分析,分析结果表明补偿方法能很好地解决控制延时导致的系统不稳定现象,大幅地提升了系统对电网阻抗的鲁棒性,最后通过实验样机验证了补偿方法的有效性与正确性。
In the stability control of LCL-type grid-connected inverter,capacitor-current-feedback active damping method is widely used because of excellent effect of resonance suppression.But the damping effect of this method is easily affected by the control delay,and the positive and negative of equivalent virtual resistance will change with the increase of frequency,and the negative virtual resistance may make the grid-connected inverter unstable under the operating condition of varying grid impedance.In order to solve this problem,a delay compensation method based on second order generalized integrator(SOGI)was proposed,the positive and negative boundary frequency of the equivalent virtual resistance could be significantly expanded.After that,the system performance after adopting compensation method was analyzed in detail.The results of analysis show that the compensation method can well solve the unstable problem caused by control delay,and the robustness of the system to the grid impedance is greatly improved.Finally,the effectiveness and correctness of the compensation method were verified by the experimental prototype.
作者
张竣淇
康朋
田昊
马磊
冯婷婷
刘松松
ZHANG Junqi;KANG Peng;TIAN Hao;MA Lei;FENG Tingting;LIU Songsong(State Grid Chongqing Economic Research Institute,Chongqing 401120,China)
出处
《电气传动》
2021年第22期15-21,共7页
Electric Drive
关键词
并网逆变器
电容电流反馈有源阻尼方法
二阶广义积分器(SOGI)
鲁棒性
延时补偿
grid-connected inverter
capacitor-current-feedback active damping method
second order generalized integrator(SOGI)
robustness
delay compensation
