穗东站换流变压器本体油位异常分析及带电处理

云广直流穗东站一台换流变压器在运行中本体油位偏高。适值迎峰度夏,云广直流满负荷运行,不可能停电处理。如果油位继续偏高则会带来严重的后果。研究了在带电的情况下该换流变压器油位高的处理。在带电情况下,由于负荷的变化,变压器内油温会持续发生变化,而温度场的变化是个缓慢的动态过程。在此动态过程中由于换流变箱体结构,油流循环,及油温油位传感器的位置等因素的影响,本体油位计显示油位与油温计的显示油温与呈非线性,且存在滞后。传统的方法不能适用于动态过程中油温油位的计算。因此,建立了在动态过程中的油温油位模型,并根据模型确定了放油量,放油之后的稳态数据表明了模型的准确性。

Analysis of the Oil Level Abnormity of Converter Transformer Body at Suidong Substation and Its On line Disposal

The oil level of a converter transformer in Suidong Station of Yun-Guang HVDC became abnormally high. Since the power load was very high in summer, it was impossible to shut down the converter transformer for this abnormity. If the oil level rises high- er, serious consequences may follow. In this research, the high oil level abnormity is analyzed during the running of the converter transformer. When the converter transformer is energized, the oil temperature would vary with the change of transformer power load. The change of oil temperature could be described as a slow dynamic process. Due to the structure of transformer oil tank, oil re- cycling and the location of oil temperature meter and oil level meter, the relationship between the oil level and temperature displayed in the meter is nonlinear and there are time-delay between the displayed oil level and oil temperature. It is impossible for traditional method to describe this complex dynamic process. Thus in this research, a dynamic model is developed and the oil volume is calculat- ed based on the model. The measurement after disposal shows the accuracy of the model.