换流变压器交流消磁及验证装置的研究  

AC degaussing and verification device of converter transformer

作　　者：刘志远 于晓军 邹洪森 张帅 史磊 郝治国[4] LIU Zhiyuan;YU Xiaojun;ZOU Hongsen;ZHANG Shuai;SHI Lei;HAO Zhiguo(State Grid Ningxia FEletrie Power Co.,Ld.Maintenanee Company,Yimchuan 750000,China;Baoding Taida Elctrie Power Equipment Co.,Ltd.,Baoding 071002,China;State Grid Ningxia Electric Power Co.,Ltd.,Yinchuan 750000,China;School of Electrical Engineering,Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]国网宁夏电力有限公司检修公司,宁夏银川750000 [2]保定市泰达电力设备有限公司,河北保定071002 [3]国网宁夏电力有限公司,宁夏银川750000 [4]西安交通大学电气工程学院,陕西西安710049

出　　处：《电力工程技术》2020年第4期194-200,共7页Electric Power Engineering Technology

基　　金：国家自然科学基金-智能电网联合基金资助项目(U1866603)。

摘　　要：为解决传统交流消磁设备存在的消磁时间长、所需电压高和设备体积大等问题,在分析换流变压器剩磁产生及传统消磁原理的基础上,提出了一种基于正弦脉冲宽度调制(SPWM)技术的低电压交流消磁法。采用高稳定性SPWM数字电源技术和高计算性能微控制器,通过数字方式精确控制SPWM电源输出交流电压幅度和频率,实现低电压条件下获取较大交流消磁电流并能够精确调节电流幅度的目的,同时低电压条件可极大减小设备体积、重量,缩短消磁时间。采用无锁相环、无严格同步要求的准同步采样技术,实现了宽频率范围交流电压、电流有效值的高精度测量。研制了换流变压器消磁及验证装置,对具有剩磁的换流变压器进行消磁试验,其消磁后的励磁涌流明显降低,体现了该装置显著的消磁效果。提出了通过对换流变压器接入低压交流测试电压,对比消磁前后变压器空载电流大小的消磁效果验证方法,试验结果表明该验证方法有效可行。In order to solve the problems of long demagnetization time,high required voltage and large equipment required of traditional AC demagnetization equipment,a low-voltage AC degaussing method based on sinusoidal pulse width modulation(SPWM) technology is proposed based on the analysis of the residual magnetization of the converter transformer and the traditional demagnetization principle. Using high stability SPWM digital power supply technology and high computing performance microcontroller,the AC voltage amplitude and frequency is output from SPWM by digitally controlling to achieve the purpose of obtaining a large AC demagnetization current under low voltage conditions and being able to accurately adjust the current amplitude,while the low voltage conditions can greatly reduce the size and weight of the equipment and shorten the demagnetization time. Using quasi-synchronous sampling technology without phase-locked loop and without strict synchronization requirements,high-precision measurement of the effective value of AC voltage and current in a wide frequency range is realized.A degaussing and verification device for the converter transformer is developed and a degaussing test is carried out for the converter transformer with residual magnetism. The results show that the demagnetizing inrush current after demagnetization is significantly reduced,reflecting the significant degaussing effect of the device. A degaussing effect verification method is proposed by connecting the low-voltage AC test voltage to the converter transformer and comparing the no-load current of the transformer before and after degaussing. The test results show that the verification method is effective and feasible.

关 键 词：换流变压器 正弦脉冲宽度调制(SPWM) 剩磁 交流消磁 励磁涌流 

分 类 号：TM432[电气工程—电器]