某油井雷击灾害调查分析及防护措施探讨

通过现场雷击灾害调查和采集雷灾现场储油罐变形处的剩磁、接地电阻等相关数据,分析了油井设施雷击灾害原因。计算出储油罐变形处的直击雷过电压高达2 100 kV、10 kV变压器感应过电压为180 kV、1 140 V电机上的过电压为20.8 kV、电视机的过电压达到4 014 V都超过了相关设备的耐压值。然后根据理论分析的结论探讨了油井储油罐、采油机、电机、变压器的直击雷防护措施,建议采取在变压器高压侧装设额定电压为15 kV的氧化锌避雷器,在后续输电线路的第1级采用8/20μs波形、通流量大于80 kA的浪涌保护器、第2级采用8/20μs波形通流量40 kA且残压小于设备耐压值的浪涌保护器的过电压保护措施。

Investigation of Lightning Disaster on an Oil Well with Protective Measures

A lightning disaster on an oil well was investigated,and the relative data,such as residual magnetism at deformed part of storage tank and grounding resistance,were collected for analyzing the causes of the lightning disaster on the oil well facilities.Calculation results show that the overvoltage on the deformed part of the storage tank under direct lightning was up to 2 100 kV,the overvoltage on the 10 kV transformer was 180 kV,the overvoltage on the 1 140 V motor was 20.8 kV,and the overvoltage on TV was 4 014 V,all of which exceed the critical values of the corresponding equipments.Consequently,some direct lightning protection measures for storage tank,oil pumping machine,electric motor and transformer are discussed on the basis of the theoretical analysis.For overvoltage protection,it is suggested that a zinc oxide lightning arrester with rated voltage 15 kV be installed at high voltage side of the transformer,a surge suppressor with 8/20 μs waveform and 80 kA SPD flow be set at the first level of subsequent transmission line,and a surge suppressor with 8/20 μs waveform,40 kA SPD flow and residual voltage lower than the equipment withstand voltage be set at the second level.