10 kV电缆测试用DC/AC充电型振荡波系统研究  

Research on DC/AC Damped AC System for 10 kV Cable Test

作　　者：王庆华 卢雨欣 沈谢林 李洪杰[2] WANG Qing-hua;LU Yu-xin;SHEN Xie-lin;LI Hong-jie(State Grid Fujian Electric Power Co.,Ltd.,Fuzhou 350004,China)

机构地区：[1]国网福建省电力有限公司,福建福州350004 [2]西安交通大学电气工程学院,陕西西安710049 [3]国网福建省电力有限公司泉州供电公司,福建泉州362000

出　　处：《电力电子技术》2021年第6期52-55,共4页Power Electronics

基　　金：国网福建省电力有限公司科技项目(52133016000X)。

摘　　要：针对目前电力电缆测试中广泛采用的振荡波(DAC)技术在直流充电阶段存在静电荷累积,可能危害电缆绝缘的问题,在此提出一种基于DC/AC变换技术的新型DAC技术和测试系统。该系统采用大功率DC/AC变换器,控制系统以谐振方式工作,产生频率、电压均可调的正弦电压,为被测电缆快速充电,解决了直流充电方式下静电荷累积的问题。通过控制DC/AC变换器输出端的双向半导体开关产生DAC电压,显著降低了 DAC转换开关的工作电压,避免了大量IGBT或LTT开关器件的使用,提高了测试系统的整体可靠性和经济性。详细阐述和论证了系统的基本原理、设计思路以及实现过程,并在一条8.7 kV/10 kV,400 m长的电缆上开展测试,表明所提DC/AC充电型高压DAC系统,能够输出峰值24 kV的DAC,满足电缆局部放电测试需求。In order to solve the problem of electrostatic charge accumulation in the DC charging stage of the damped AC(DAC)technology,which is widely used in power cable testing,and may harm the cable insulation,a new DAC technology and testing system based on DC/AC conversion technology is proposed.The system uses high-power DC/AC converter,and the control system works in resonant mode to generate sinusoidal voltage with adjustable frequency and voltage,which can quickly charge the tested cable and solve the problem of static charge accumulation in DC charging mode.By controlling the bi-directional semiconductor switch at the output end of DC/AC converter to generate DAC wave,the working voltage of DAC transfer switch is significantly reduced,a large number of IGBT or LTT switching devices are avoided,and the overall reliability and economy of the test system are improved.The basic principle,design idea and implementation process of the system are described and demonstrated in detail.The test is carried out on a 8.7 kV/10 kV,400 m long cable.The results show that the proposed DC/AC charging high voltage DAC system can output 24 kV DAC at peak value,meeting the requirements of cable partial discharge test.

关 键 词：变换器 振荡波 电力电缆测试 静电荷累积效应 

分 类 号：TM46[电气工程—电器]