摘要
三相Buck型动态电容器(D-CAP)正常补偿无功时,在电网背景谐波的影响下,会产生谐振的问题。本文首先分析了Buck型D-CAP的基本结构和原理;接着通过对D-CAP自身阻抗和电网阻抗的建模,分析了谐振产生的原因,并计算出了相应的谐振点;同时针对其谐振频率附近的谐波,提出了通过检测D-CAP的电容电压构建反馈环路,实现有源谐振阻尼的控制方法;最后,提出了一种D-CAP在进行无功补偿的同时,实现谐波抑制和谐振阻尼的复合控制策略。通过该策略,谐振引起的网侧电流谐波畸变得到了明显抑制,网侧电流谐波含量达到了电能质量标准。实验结果验证了理论分析的正确性。
Three-phase Buck-type dynamic capacitor(D-CAP),in case of normal reactive power compensation will cause resonance under influence of background harmonics of grid.In this paper,the basic structure and principle of Buck type D-CAP is analyzed,the reason for the resonance generation is analyzed through the modeling of self-impedance of D-CAP and impedance of grid and the corresponding resonance point is calculated.At the same time,as for the harmonics near its resonance frequency,it is proposed to build the feedback loop by way of detecting capacitance and voltage of D-CAP so to achieve the control method of active resonance damping.Finally,the achievement of composite control strategy for harmonic suppression and resonance damping by the D-CAP is proposed at the same time of performing reactive power compensation.The current harmonic distortion of grid side due to resonance is remarkably suppressed throughout the strategy,and the current harmonic contents at the grid side reaches power quality standard.The correctness of theoretical analysis is verified by the experimental result.
作者
张三洪
戴珂
熊亮雳
陈新文
汪晓胜
ZHANG Sanhong;DAI Ke;XIONG Liangli;CHEN Xinwen;WANG Xiaosheng(Central China Branch of State Grid Corporation of China,Wuhan 430077,China;State Key Laboratory of Advanced Electromagnetic Engineering and Technology,School of Electrical and Electronic Engineering,Huazhong University of Science and Technology, Wuhan 430074,China;China-EU Institute for Clean and Renewable Energy, Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《电力电容器与无功补偿》
北大核心
2018年第5期24-29,共6页
Power Capacitor & Reactive Power Compensation
基金
国家自然科学基金(51277086)
关键词
动态电容器
无功补偿
谐波抑制
谐振阻尼
复合控制策略
dynamic capacitor
reactive power compensation
harmonic suppression
resonance damping
composite control strategy
