直流绝缘电阻检测在光储充检系统中的应用研究  

Research on the Application of DC Insulation Resistance Detection to Photovoltaic Storage Charging Inspection System

作　　者：章云区 熊刚 ZHANG Yun-qu;XIONG Gang(Fujian Nebula Electronics Co.,Ltd,Fuzhou 350015,China)

机构地区：[1]福建星云电子股份有限公司,福建福州350015

出　　处：《电工电气》2023年第10期58-63,共6页Electrotechnics Electric

摘　　要：针对光储充检应用中对绝缘检测模块小体积、高精度、大量程、宽工作温度范围、宽工作电压的要求,提出改进型不平衡电桥电路并推导公式,在此基础上设计了绝缘电阻检测电路。以GD32单片机为控制核心,以24位ADC芯片、精密基准源和低温漂电阻构成前端采集电路,以带电源SPI隔离芯片实现高低压信号隔离,以MOS光耦和高压继电器进行不平衡电桥切换。实验结果表明,该方案能准确检测光储充检系统中充电桩直流母线绝缘电阻值,在-40~+70℃温度范围、200~1000 V电压范围、1 kΩ~30 MΩ量程范围内,绝缘电阻测量误差小于或等于±1%,且设计集成度高、体积小巧,满足光储充检系统中分体桩的安装空间要求。Insulation detection modules in the photovoltaic storage charging inspection system need to meet the requirements of small volume,high precision,large range,wide range of operating temperature and working voltage,so the paper proposes an improved imbalance electric bridge circuit and derives its formula,and then designs the insulation resistance detection circuit on this basis.This circuit,taking the GD32 single chip microcomputer as the controlling core,uses a 24-bit ADC chip,a precision reference source and a low-temperature drift resistor as the front-end sampling circuit.Then,it uses the SPI isolator with power supply to realize the signal isolation between high and low voltage,and the MOS optical coupler and high voltage relays to switch imbalance electric bridge.The experimental results show that this scheme can accurately measure the insulation resistance of charging pile DC bus in the photovoltaic storage charging inspection system.The error of insulation resistance measurement is less than or equal to±1%in the range of-40~+70℃,200~1000 V and 1 kΩ~30 MΩ.More-over,the insulation detection module has high integration and small volume,meeting the space requirement of installing split piles in the photovoltaic storage charging inspection system.

关 键 词：绝缘电阻 充电桩 不平衡电桥 光储充检系统 

分 类 号：TM855[电气工程—高电压与绝缘技术] TM934.31