摘要
整流桥式过电压抑制装置能够显著地抑制电炉变压器空载开断时的过电压,但其工作机理和应用尚未得到系统论证。文中在电磁暂态数值仿真分析的基础上,分析了该装置抑制过电压的机理,即利用大容量电解电容器吸收截流后电路中存储的电磁能量,同时过电压的幅值因较小的变压器绕组漏感而得到限制,典型情况下该装置可将过电压降至1.15倍。另外,给出了过电压幅值和倍数的估算公式,分析了变压器的短路阻抗、容量、空载截流值以及端口对地电容等因素对电压倍数的影响,变压器的短路阻抗越小或容量越大,越有利于降低过电压倍数。
A rectification-bridge type over-voltage suppression equipment can significantly suppress over-voltage occurred during a no-load electric furnace transformer interrupting. However, the mechanism and application of the equipment have not been systematically analyzed. Based on electromagnetic transient analysis, over-voltage suppression mechanism of the equipment is analyzed. The equipment absorbs electromagnetic energy stored in the circuit with high-capacity electrolytic capacitor after current chopping, and the over-voltage is also limited by small leakage inductance of the transformer winding. In typical condition, the over-voltage can be limited to 1.15 rated. In addition, an estimation formula of over-voltage is derived as well. The main influencing factors, such as short circuit impedance, capacity, chopping current, and terminal-to-earth capacitance of the transformer, to the over-voltage are evaluated, It is concluded that the less the short circuit impedance or the larger the capacity of the transformer, the smaller the over-voltage.
出处
《电力系统自动化》
EI
CSCD
北大核心
2009年第9期73-76,共4页
Automation of Electric Power Systems
基金
国家自然科学基金资助项目(50877038)~~
关键词
整流桥
过电压抑制
空载变压器
机理
rectification-bridge
over-voltage suppression
no-load transformer
mechanism
