电工技术学报2025,Vol.40Issue(22):7375-7386,12.DOI:10.19595/j.cnki.1000-6753.tces.241941
电磁式漏电断路器保护特性分析与稳健性设计
Protection Characteristics Analysis and Robustness Design of Electromagnetic Residual Current Device
摘要
Abstract
Residual current devices(RCDs)are critical electrical safety devices that can quickly cut off the power supply when leakage faults occur in power lines or electrical equipment,thus preventing electrical fires and ensuring personal safety.Among them,electromagnetic RCDs are highly valued due to their stable leakage protection characteristics,excellent anti-interference capability,and rapid response time.This paper focuses on the series-parallel compensation capacitor in the leakage protection driving circuit of fast-acting electromagnetic RCDs and the robustness of leakage protection characteristics.The matching relationship between the series-parallel compensation capacitor and residual current transformer(RCT)is determined,and relevant parameters are optimized to enhance the robustness of electromagnetic leakage protection characteristics.The main research work and conclusions are as follows. (1)The main components of electromagnetic RCD are analyzed.The transmission characteristics of RCT are affected by the excitation characteristics of the iron core and the driving circuit.The key factor for the reliable operation of the magnetic release is the excitation of ampere-turns,and the topology of the driving circuit determines the leakage protection characteristics.The working principle of the compensation circuit with a series-parallel capacitor is analyzed,and the relationship between circuit characteristics and element parameters is studied. (2)The topology of the leakage driving circuit with a series-parallel compensation capacitor is investigated.The influence of compensation capacitors and RCT on leakage protection characteristics is explored.The matching principle of compensation capacitors and their relationship with leakage protection value are studied,and the variation characteristics of the capacitor matching curve under different protection values are determined.It is suggested that the exciting inductance of RCT should be designed to be greater than the critical inductance to reduce the influence of compensation capacitor dispersion on the leakage protection value.The impact of magnetic parameters of RCT on leakage protection characteristics is studied,and the influence of hysteresis and magnetic saturation characteristics on the matching principle of compensation capacitors is analyzed.The increase in saturation magnetic flux density Bs and remanence Br leads to a decrease in protection value.In contrast,the increase in coercive force Hc leads to an increase. (3)The dispersion influence of compensation capacitors and RCT magnetic parameter on leakage protection characteristics is studied.The range of the compensation capacitor is determined through sensitivity analysis.Saturation magnetic flux density Bs shows the least influence on protection value,coercive force Hc shows the second least influence,and remanence Br shows the most significant influence.When the compensation capacitor is on the left side of the knee point of the right half of the matching curve,the leakage protection value is the least affected by the dispersion of magnetic parameters.A comprehensive design method for RCT and compensation capacitors is proposed,and the optimal design scheme is determined by an orthogonal method.Under the same component parameter fluctuation,the fluctuation range of leakage protection value is reduced by 46.04%after parameter optimization,enhancing the robustness of leakage protection characteristics.关键词
电磁式漏电断路器/漏电保护特性/电路拓扑分析/剩余电流互感器/稳健性设计Key words
Electromagnetic residual current device(RCD)/leakage protection characteristics/circuit topology analysis/residual current transformer(RCT)/robustness design分类
动力与电气工程引用本文复制引用
李奎,于明浩,牛峰,武一,卢志伟..电磁式漏电断路器保护特性分析与稳健性设计[J].电工技术学报,2025,40(22):7375-7386,12.基金项目
国家自然科学基金资助项目(51977059). (51977059)