摘要
分布式电源通过电力电子装置并网引发的谐波问题日益凸显,采用滤波环节去除电网侧高次谐波成为重要解决方案。其中,LCL滤波是一种有效的滤波结构,但其高阶特征使系统控制策略更加复杂。为提高LCL滤波器接入后并网变流器的谐波抑制能力和运行稳定性,推导了LCL滤波全桥变流器运行控制数学模型,提出了LCL滤波结构设计和参数计算方法,设计了基于准比例谐振控制和比例积分控制的电压-电流双闭环控制策略,提出了基于带通滤波器和信号限幅环节的控制策略改进方案。算例测试表明,本文方法能够基于LCL滤波器实现精准的谐波抑制,同时避免高阶滤波器谐振问题,改善了LCL滤波并网变流器在复杂运行环境下的谐波抑制能力和控制稳定性。
The distributed power generators connected to the grid via power electronic devices result in prominent harmonic problems.Filters are pivotal in mitigating the high-order harmonics on the grid side,with the LCL filter stan-ding out as an effective filtering structure.However,its high-order nature complicates the system control.This study derives a mathematical model of a full-bridge converter integrated with an LCL filter to improve the harmonic suppression capability and operational stability of grid-connected converters.A design methodology for the LCL filter′s structure and parameter calculation is also proposed.A voltage-current dual closed-loop control strategy is developed using quasi-proportional resonance control combined with proportional-integral control.An advanced control strategy is proposed employing a band-pass filter paired with an amplitude limiter.Empirical tests indicate that the proposed method,based on the LCL filter,can adeptly suppress harmonics,avoid the resonance challenges associated with the high-order filter,and enhance the filtering capability and control stability of the grid-connected converters with LCL filter under intricate operational conditions.
作者
兰岚
潘星辰
兰德刚
LAN Lan;PAN Xingchen;LAN Degang(State Grid Tianjin High Voltage Company,Tianjin 300232,China;Party School of State Grid Tianjin Electric Power Company,Tianjin 300171,China;State Grid Tianjin Cable Company,Tianjin 300160,China)
出处
《宁夏电力》
2023年第5期51-57,65,共8页
Ningxia Electric Power
