智能塑壳断路器电流互感器设计

打开文本图片集

关键词：智能塑壳断路器；电流互感器取能；匝数设计；PWM控制中图分类号：TM561文献标志码：A 文章编号：2095-8188（2025）07-0030-09DOI：10.16628/j.cnki.2095-8188.2025.07.005

Abstract： In an intellgent molded case circuit breaker（MCCB），the current transformer （CT） not only collects current signals butalso supplies power to theelectronic tripunit.Ifthedesign is inadequate，insufficient power can be provided at low current levels or when the load impedance is high，leading to core saturation， secondary-side currentdistortion，therebycausing measurement errors.Toaddress these issues，a 63Arated intellgent MCCB is selected as the research subject.The range of CT turns meeting the requirment of measurement and energy extractions istheoreticallyderived.Then，Ansyssimulationsareconducted to determine theoptimal numberof turns.Additionally，a MOSFET is introduced on theCT's secondary side to control the load-side voltage by means of PWM.Simulation and experimental results show that the designed CTcan maintain undistorted output waveformswith an equivalent load impedance of1 kΩ ina current range of 0.4In to 10In .Across the entire current range，the solution ensures accurate measurement while meeting power supply requirements.

Key words：intelligent molded case circuit breaker（MCCB）；energy extraction from current transformer；turns design;PWM control

0 引言

智能塑壳断路器（MCCB）中的电流互感器（CT）具有一定的特殊性，不仅需要提供电流检测信号，而且需为电子脱扣器提供能量[1-2]。（剩余9539字）