摘要
针对低压微电网中由于线路阻抗呈阻感性以及不匹配,使得常规虚拟同步发电机(VSG)控制的多逆变器往往存在功率耦合和无功分配不均的问题,提出了一种基于耦合点电压估计的多VSG无功分配控制策略.首先,引入虚拟阻抗技术将等效输出阻抗设计成感性,以实现功率解耦;其次,对公共耦合点电压进行准确估计,在励磁控制器中引入基于公共耦合点估计电压的负反馈和积分环节,以实现线路阻抗对无功功率的解耦;最后,引入动态虚拟阻抗环节,并采用无功功率调节其大小,降低了公共耦合点电压的跌落,并减少了线路阻抗不匹配对环流的影响,提高了电能质量.仿真结果验证了所提出控制策略的有效性.
Because of the resistance and mismatch of line impedance in low-voltage microgrid,the multi-inverters controlled by conventional virtual synchronous generator(VSG)often have problems with power coupling and uneven reactive power distribution.To address these issues,a reactive power distribution control strategy for multi-VSG based on coupling point voltage estimation is proposed.First,virtual impedance technology is introduced to design equivalent output impedance as inductance to realize power decoupling.Secondly,the voltage of the common coupling point is accurately estimated.In order to decouple the line impedance from the reactive power,negative feedback and an integral link based on the common coupling point estimation voltage is introduced into the excitation controller.Finally,a dynamic virtual impedance mechanism is implemented.The reactive power is used to adjust the voltage drop of the common coupling point,and the influence of the impedance mismatch on the circulating current is reduced,thereby the power quality is improved.The simulation results verify the effectiveness of the proposed control strategy.
作者
杨巧玲
胡方彬
张晓雨
任秋艳
YANG Qiao-ling;HU Fang-bin;ZHANG Xiao-yu;REN Qiu-yan(College of Electrical and Information Engineering,Lanzhou University of Technology,Lanzhou 730050,China;School of Information Engineering and Artificial Intelligence,Lanzhou University of Finance and Economics,Lanzhou 730101,China)
出处
《兰州理工大学学报》
北大核心
2025年第2期94-99,共6页
Journal of Lanzhou University of Technology
基金
国家自然科学基金(51767018)
甘肃省自然科学基金(23JRRA836,22JR5RA556)
甘肃省高等学校青年博士基金(2022QB-104)。
关键词
虚拟同步发电机
逆变器并联
动态虚拟阻抗
功率分配
环流抑制
virtual synchronous generator
parallel inverter
dynamic virtual impedance
powerp sharing
circulation current suppression
