500kV大型油浸式电力变压器过负荷运行风险控制

为了控制和减少500kV大型油浸式电力变压器过负荷运行所造成的危害，文章对如何评估大型油浸式电力变压器正常周期性过负荷和事故过负荷能力进行了研究。并应用查负载表法和热点温度计算法评估大型油浸式电力变压器正常周期性过负荷和事故过负荷能力，给出了500kV大型油浸式电力变压器事故过负荷运行风险的应对措施。通过实例分析，证明基于变压器自身的温升试验数据，采用热点温度计算法预先评估变压器过负荷能力，可以有效控制电网风险，保障供电安全。

Risk Control of Overload Operation in 500kV Large Oil-immersed Power Transformer

How to assess the overload capacity of large oil-immersed power transformer under the conditions of normal periodic overload and accident overload is studied to control and reduce the overload harms to 500kV large oil-immersed power transformer. Method of loop up load table and hot-spot temperature calculation are applied to assess the overload capacity of large oil-immersed power transformer under the conditions of normal periodic overload and accident overload, and countermeasure against risk of accident overload in 500kV large oil-immersed power transformer is proposed. According to the analysis of examples, method of hot - spot temperature calculation can assess the overload capacity of transformer based on temperature rise test data of the transformer itself, which can control effectively power network operation risk and guarantee the security of power supply.