| 引用本文: | 栗磊,宋小会,刘星,等.串变调压电炉变压器差动保护研究[J].电力系统保护与控制,2014,42(16):118-121.[点击复制] |
| LI Lei,SONG Xiao-hui,LIU Xing,et al.Research on differential protection of the furnance transformer which adopts series transformer used for voltage-regulation[J].Power System Protection and Control,2014,42(16):118-121[点击复制] |
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| 摘要: |
| 针对电炉变压器频繁调压且调压范围宽的特点，提出根据当前电炉变压器有载调压档位实时计算差动保护的平衡系数方法。该方法首先将3个单相电炉变压器档位信息经有载调压档位控制器转换为BCD码信息；然后差动保护装置通过开关量方式接入转换后的BCD码信息，并解码还原为当前实际档位；最后根据变压器调压总档位、各相变压器当前档位、低压侧标称最高电压及最低电压，计算各相变压器低压侧当前工作电压，再结合变压器额定容量、高压侧额定电压，按相实时计算差动保护平衡系数。这种方法解决了电炉变压器差动保护的差动电流计算不正确的难题，工程实践表明该方法明显增加差动电流计算正确性提高差动保护灵敏度。 |
| 关键词: 电炉变压器保护 纵差保护 平衡系数 有载调压 |
| DOI：10.7667/j.issn.1674-3415.2014.16.020 |
| 投稿时间：2013-11-06修订日期：2013-12-25 |
| 基金项目: |
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| Research on differential protection of the furnance transformer which adopts series transformer used for voltage-regulation |
| LI Lei,SONG Xiao-hui,LIU Xing,LIANG Ya-bo,LI Guo-bin,JIANG Rui-zhi,GUO Zhi-zhong |
| (Ningxia Power Scientific Institute Center, Yinchuan 750001, China;School of Electrical Engineering and Automation, Harbin Institute of Technology, Harbin 150001, China;XJ Electric Company Limited, Xuchang 461000, China) |
| Abstract: |
| The three single-phase on load transformer tap changing furnace transformer has the advantages of wide voltage controlled range and frequent voltage control. This paper presents the differential protection device of the furnance transformer should calculate the balance coefficient of the differential protection in real time. First, the gear information of 3 single-phase electric furnace transformer is converted to BCD code information through the OLTC gear controller; then the differential protection device accesses the converted BCD code through switch signal and decodes the information; finally, according to the transformer voltage total gears, each phase current transformer tap, low voltage side of the highest and lowest voltage nominal voltage, each phase current working voltage of low voltage side is calculated, combined with the transformer rated capacity, rated voltage of the high voltage side, the differential current calculation is adjusted in real time according to the current tap of the furnace transformer. This method solves the differential current electric transformer differential protection calculation problem is not correct. The engineering practice shows that the methods can increase the accuracy of the differential current calculation and significantly improve the differential current protection sensitivity. |
| Key words: furnance transformer differential protection of furnance transformer balance coefficient load voltage regulation |
