某750kV单相自耦变压器低压侧三相电压不平衡问题分析计算  

Analysis and Calculation of Three-phase Voltage Imbalance at Low Voltage Side of Single Phase Auto Transformer at 750 kV Substation

作　　者：张立成 杨利民 颉雅迪 李山 郑义 ZHANG Licheng;YANG Limin;XIE Yadi;LI Shan;ZHENG Yi(State Grid Xinjiang Electric Power company,Urumqi 830011,China;State Grid Xinjiang Electric Power Research Institute,Urumqi 830011,China)

机构地区：[1]国网新疆电力有限公司,乌鲁木齐830011 [2]国网新疆电科院,乌鲁木齐830011

出　　处：《电力电容器与无功补偿》2023年第6期45-52,共8页Power Capacitor & Reactive Power Compensation

摘　　要：变压器在电力系统的运行中扮演着重要角色,但在运行过程中会出现三相电压不平衡的现象,严重影响设备正常工作,不利于电网安全稳定运行。针对此问题,本文基于三相电压不平衡的机理,利用EMTPE建立仿真分析模型,研究750kV主变投运过程中66kV侧母线三相电压不平衡的原因,并分析三相电压不平衡对二次设备的影响。结果表明,三相变压器各绕组等效电容存在明显差异是电压不平衡的主要原因,不平衡电压对二次设备运行无影响。该研究结果对超高压大容量输变电系统主变的投运具有重要参考价值。Transformer plays an important role in the operation of power system and will,however,have the three-phase voltage imbalance problem during operation,which seriously affects the normal operation of the equipment and is also not conducive to the safe and stable operation of the power grid.In view of this issue,the reason of three phase voltage imbalance of 66 kV busbar side during operation of 750 kV main transformer is studied on the basis of mechanism of three-phase voltage imbalance and by way of setting up simulation analysis model by using EMTPE and moreover,the influence of three phase voltage imbalance on the secondary equipment is analyzed.The results show that the existence of obvious difference in the equivalent capacitance of each winding of the three-phase transformer is the main reason for the voltage imbalance,and the imbalanced voltage has no effect on the operation of the secondary equipment.The research results have an important reference for the commissioning of the main transformer of the EHV large capacity power transmission and transformation system.

关 键 词：主变压器 电压不平衡 等效电容 二次设备 EMTPE 

分 类 号：TM411.3[电气工程—电器]