摘要
弱电网条件下,电网阻抗的存在会增加并网电流的谐波含量,甚至造成光伏并网逆变器不稳定。该文以三相LCL型逆变器为研究对象,以阻抗模为出发点,使用阻抗稳定判据分析弱电网在常规电流控制方式下的系统稳定性降低机理,提出在电容电流前馈支路上附加超前校正网络的相角补偿控制策略,通过提高系统输出阻抗的相角提高并网逆变器稳定性。仿真结果表明,该方法可有效解决较高电网阻抗带来的失稳现象,并具有良好的稳态性能和动态响应能力。
In a weak grid system,grid impedance variations will increase harmonic current of the grid-connected inverter,even system stability will be significantly influenced. This paper establishes the impedance model,the impedance stability criterion is used to analyze the stability of weak grid system with LCL inverter under traditional current control. A phase angle compensation control strategy with capacitor current feedback is proposed,then the phase angle of output impedance of the system is increased,it will improve the stability of grid-connected inverter under weak grid. The simulation results show that the proposed method can effectively solve the instability caused by high grid impedance,the system has good steady-state performance and rapid dynamic response.
作者
杨兴武
王楠楠
王毅
周彬
Yang Xingwu;Wang Nannan;Wang Yi;Zhou Bin(Engineering Research Center of Green Energy Grid-Connected Technology,Shanghai University of Electric Power,Shanghai 200090,China;Shanghai Donghai Wind Power Co.,Ltd.,Shanghai 200090,China)
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2020年第5期312-318,共7页
Acta Energiae Solaris Sinica
基金
上海绿色能源并网工程技术研究中心资助项目(13DZ2251900)。
关键词
稳定性
谐波
并网逆变器
弱电网
相角补偿控制
阻抗
stability
harmonic
grid-connected inverters
weak grid
phase-angle compensation control
impendance
