近年来,高压直流输电技术在国内外迅速发展,直流电流互感器(direct-current current transformers,DCCT)是高压直流输电系统中的重要测量设备。为保证其准确可靠,DCCT投运前和停电维护时需现场校准,而国内外相关校准技术匮乏。本文在分析国内外DCCT现场校准技术及相关的电流标准器技术基础上,采用了一种高压DCCT现场校准系统,主要包括直流电流源、作为标准器的磁调制式直流电流比较仪(dc current comparator,DCC)和具有光纤数字同步功能的DCCT校验仪。重点分析了校准系统现场可能受到的干扰因素对其测量不确定度的影响,提了出解决问题的具体方法和措施。从DCC原理上论证了直流电流源所含的谐波对DCC直流测量不造成影响,同时能够对谐波分量进行监测。提出了一种直流-谐波双回路叠加的谐波测试系统,对DCC的谐波响应特性进行测试,验证理论分析。为改善现场校准使用时电磁环境,提出了蝶形母线环方法,能够有效的减小现场布线带来的电磁干扰。对于标准器DCC现场使用时可能遇到的母线偏心和邻近通流导体等干扰情况进行仿真分析,在优化磁屏蔽结构的基础上,研制了DCC样机,经中国计量科学研...
【英文摘要】
Recent years, the technology of high voltage direct current transmission is in rapid development home and abroad. Direct-Current current transformer(DCCT) is an important measurement equipment in high-voltage direct current transmission system. In order to ensure its accurate and reliable, field calibration is needed before the DCCT putting into operation and at the time of outage maintenance. However, there are few relevant calibration technologies at home and abroad.Based on the analysis of DCCT field cal...