摘要
因在传统非隔离型光伏并网逆变器中存在交、直流解耦拓扑中点电压悬浮问题,导致漏电流无法被有效抑制,因此提出一种有源T型中点箝位控制TAC-Heric(T-type active clamp Heric)。基于传统Heric拓扑技术,在其拓扑分压电容中点与续流桥臂中点之间添加T型通路,以此来对中点电压进行有效箝位并抑制漏电流。此外,基于TACHeric控制,对PI、PR以及QPR控制器的特性进行分析,在此基础上,采用PI+QPR综合控制策略,有效降低了并网电流谐波畸变率,提高了系统的电能质量。最后,理论和仿真分析验证了TAC-Heric能更好地抑制漏电流以及所提控制策略的可行性。
Due to the midpoint voltage levitation problem of AC and DC decoupling topology in traditional nonisolated photovoltaic grid-connected inverters,the leakage current cannot be completely suppressed.Therefore,this paper proposed an active T-type midpoint clamp control TAC-Heric(T-type active clamp Heric).Based on the traditional Heric topology technology,a T-shaped path was added between the midpoint of the topological voltage divider capacitor and the midpoint of the freewheeling bridge arm to effectively clamp the midpoint voltage and suppress leakage current.In addition,based on TAC-Heric control,the characteristics of PI,PR and QPR controllers were analyzed.On this basis,the PI+QPR comprehensive control strategy was adopted to effectively reduce the harmonic distortion rate of grid-connected current and improve the system reliability.Finally,theoretical and simulation analysis verifies that TAC-Heric can better suppress leakage current and the proposed control strategy is feasible.
作者
古纯松
陈众
谢辉
马希永
GU Chunsong;CHEN Zhong;XIE Hui;MA Xiyong(Key Laboratory of Intelligent Power Grid Operation and Control,Changsha University of Science and Technology,Changsha Hunan 410114,China)
出处
《电源技术》
CAS
北大核心
2022年第8期930-934,共5页
Chinese Journal of Power Sources
关键词
光伏并网逆变器
漏电流
中点箝位
PI+QPR控制器
photovoltaic grid connected inverter
leakage current
neutral point clamping
PI+QPR controller
