摘要
在新能源发电系统中,通过将逆变器并联接入电网扩大了并网容量。由于电网存在阻抗,降低了逆变器的稳定性,也加大了逆变器对负载中电能质量的治理难度,因此文中对一种弱电网下并联逆变器治理负载中电能质量的问题进行了研究。首先,以H∞重复控制结合电压前馈控制作为电流内环控制策略,分析了弱电网下单台及多台并联逆变器的稳定性能,采用前馈通道串联复数滤波器及前向通道串联超前校正环节的复合策略提高逆变器的稳定性;然后,利用电流检测算法分离负载中的不平衡、谐波及无功电流,实现并联逆变器对不平衡、非线性及无功等负载引起的电能质量问题的治理;最后,在Simulink中进行仿真实验,仿真结果表明在弱电网条件下利用并联逆变器能够对多种负载的电能质量问题进行治理。
In the new energy power generation system,the inverter is connected to the grid in parallel,which expands the grid capacity.In addition,due to the existence of grid impedance,the stability of the inverter is reduced and the difficulty of power quality governance in the load increases.The problem of power quality governance of parallel inverter in weak current network is studied.Firstly,H∞repetitive control combined with voltage feedforward is used as the current inner loop control strategy and the stability performance of single and multiple parallel inverters in weak current network is analyzed.The composite strategy of feedforward channel series complex filter and forward channel series lead correction link is adopted to improve the stability of inverter.Secondly,the current detection algorithm is used to separate the unbalanced,harmonic and reactive currents in the load,which solves the governance of power quality problems caused by unbalanced,nonlinear and reactive loadd.Finally,the simulation experiment is carried out in Simulink.The simulation results show that the power quality problems of multiple loads under the condition of weak power grid can be solved by parallel inverter.
作者
张成
赵涛
朱爱华
陶以彬
孙权
曹芸凯
ZHANG Cheng;ZHAO Tao;ZHU Aihua;TAO Yibin;SUN Quan;CAO Yunkai(School of Automation,Nanjing Institute of Technology,Nanjing 211167,China;State Grid Zhejiang Electric Power Co.,Ltd.Xinchang Power Supply Company,Shaoxing 312099,China;China Electric Power Research Institute Company,Nanjing 210003,China)
出处
《电力工程技术》
北大核心
2022年第3期224-230,共7页
Electric Power Engineering Technology
基金
国家自然科学基金资助项目(61901212)。
关键词
并联逆变器
电能质量
稳定性
电流检测
弱电网
H∞重复控制
parallel inverter
power quality
stability
current detection
weak current network
H∞repetitive control
