基于过电压衰减比的柔性接地控制参数设计方法  

Flexible Grounding Control Parameters Design Based on Overvoltage Attenuation Ratio

作　　者：栾晓明 李伟超 武守远 贾春娟[1] 王尊贤 LUAN Xiaoming;LI Weichao;WU Shouyuan;JIA Chunjuan;WANG Zunxian(Key Laboratory of Power System Intelligent Dispatch and Control(Shandong University),Ministry of Education,Jinan 250061,Shandong Province,China)

机构地区：[1]电网智能化调度与控制教育部重点实验室(山东大学),山东省济南市250061

出　　处：《电网技术》2023年第6期2575-2582,共8页Power System Technology

基　　金：国家电网有限公司总部科技项目(5400-202199279A-0-0-00)。

摘　　要：为实现柔性接地装置对中性点电压的准确控制,提出过电压衰减比的概念,并以配电网不接地系统为例提出了控制系统设计方法。首先,分析了不接地系统的中性点过电压产生机理,建立了柔性接地装置接入配电网的等效模型。其次,给出了双闭环控制系统的框图并推导出双闭环控制下的零序输出电压表达式,在此基础上提出了过电压衰减比的概念。文中以双比例控制器为例,提出了基于过电压衰减比指标的控制系统参数设计方法,通过内、外环参数解耦设计,实现了衰减比和系统稳定性的独立控制。最后,搭建了10k V配电网不接地系统仿真模型和低压实验回路,验证了所提设计方法有效性。In order to realize the accurate control of the neutral point voltage by the flexible grounding device,the concept of overvoltage attenuation ratio is introduced.Taking the ungrounded system of the distribution network as an example,a control system design is proposed.First,the generation mechanism of the neutral point overvoltage of the ungrounded system is analyzed,and the equivalent model of the flexible grounding device connected to the distribution network is established.Secondly,the block diagram of the double closed-loop control system is given and the zero-sequence voltage expression under the double closed-loop control is derived.On this basis,the concept of overvoltage attenuation ratio is considered.Taking the dual proportional controller as an example,a control system parameter design based on the overvoltage attenuation ratio index is presented.Through the decoupling design of the inner and outer loop parameters,the independent control of the attenuation ratio and the system stability is realized.Finally,a 10kV distribution network ungrounded system simulation model and low-voltage experimental circuit are built to verify the effectiveness of the proposed design.

关 键 词：配电网 不接地系统 中性点过电压 柔性接地 过电压衰减比 

分 类 号：TM721[电气工程—电力系统及自动化]