摘要
自同步电压源逆变器(SVI)在电网电压不对称工况下实现三相并网电流平衡控制,同时兼顾离网独立运行时机端电压控制稳定性,是实际工程应用中面临的挑战之一。首先,在简要阐述SVI工作原理的基础上,文中详细分析了电网不对称条件下,常规正负序分离控制应用到SVI的局限性和系统离网独立运行时不稳定的机理。然后,基于SVI单模式控制思想,提出一种基于准谐振控制器的SVI负序电流抑制策略,在电网不对称工况下实现了入网电流输出平衡,同时保证了SVI在并/离网模式切换以及离网(含多机并联)独立工作时的系统稳定性。最后,仿真和实验结果验证了所提出的系统控制策略的正确性和有效性。
It is one of the challenges faced in practical engineering applications of the self-synchronous voltage source inverter(SVI)to realize balance control of the three-phase current under asymmetric grid voltage conditions when connected to the grid, and take into account the stability of the terminal voltage control when it runs independently off the grid. First, under the asymmetric condition of the power grid, on the basis of a brief description of the working principle of the SVI, this paper analyzes in detail the limitations of applying in conventional positive and negative sequence separation control to SVI, and the instability mechanism when the system operates independently from the grid. Then, based on the single-mode control idea of the SVI, a suppression strategy of SVI negative sequence current based on a quasi-resonant controller is proposed, which achieves the balance of current output to the grid under the asymmetric grid condition. At the same time, the system stability of the SVI is guaranteed when it switches between on-grid and off-grid modes and operates off-grid(including multi-machine parallel) independently. Finally,simulation and experimental results verify the correctness and effectiveness of the proposed system control strategy.
作者
韦徵
姬秋华
王伟
王彤
王俊辉
王腾飞
WEI Zheng;JI Qiuhua;WANG Wei;WANG Tong;WANG Junhui;WANG Tengfei(NARI Group Corporation(State Grid Electric Power Research Institute),Nanjing 211106,China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2021年第10期124-131,共8页
Automation of Electric Power Systems
基金
国家电网公司科技项目“高比例新能源电力系统的自同步电压源型新能源发电关键技术研究”。
关键词
自同步电压源逆变器
电网不对称
准谐振控制
稳定性分析
self-synchronous voltage source inverter(SVI)
asymmetry of power grid
quasi-resonant control
stability analysis
