摘要
随着新能源发电系统大规模接入电网,三相并网逆变器的稳定性问题日益突出。电网阻抗变化、弱电网运行条件及多逆变器并联交互等因素,易引发系统振荡甚至失稳。本文提出一种基于阻抗优化的主动控制策略,主要是增强逆变器在宽电网阻抗范围内的稳定性。该策略通过实时分析逆变器输出阻抗与电网阻抗的交互特性,在控制环路中引入自适应虚拟阻抗补偿环节,重塑逆变器的输出阻抗特性,使其满足广义奈奎斯特稳定判据。仿真与实验结果表明,所提方法能有效抑制中高频谐振,提升系统在弱电网条件下的稳定裕度,同时不影响基波控制性能。该策略无需额外硬件成本,易于在现有逆变器控制架构中实现,为高渗透率新能源并网系统提供了可行的稳定性解决方案。
With the large-scale integration of new energy generation systems into the power grid,the stability issue of three-phase grid connected inverters has become increasingly prominent.Factors such as changes in grid impedance,operating conditions of weak grids,and parallel interaction of multiple inverters can easily cause system oscillations and even instability.This article proposes an active control strategy based on impedance optimization,which mainly enhances the stability of inverters in a wide range of grid impedances.This strategy introduces an adaptive virtual impedance compensation loop in the control loop by analyzing the interaction characteristics between the inverter output impedance and the grid impedance in real time,reshaping the output impedance characteristics of the inverter to meet the generalized Nyquist stability criterion.Simulation and experimental results show that the proposed method can effectively suppress mid to high frequency resonance,improve the stability margin of the system under weak power grid conditions,and not affect the fundamental wave control performance.This strategy does not require additional hardware costs and is easy to implement in existing inverter control architectures,providing a feasible and stable solution for high penetration new energy grid connected systems.
作者
张琰
ZHANG Yan(Shaanxi Hengjian Electric Power Construction Development Co.,Ltd.,Xi'an 710061,P.R.China)
出处
《灯与照明》
2025年第6期194-196,共3页
Light & Lighting
关键词
三相并网逆变器
稳定性
阻抗优化
控制策略
three-phase grid connected inverter
stability
impedance optimization
control strategy
