【摘要】 敞开式的结构设计导致电容式电压互感器(capacitor voltage transformer,CVT)运行时受周围设备产生的电场影响,以及外界产生的杂散电容参与电容单元分压比计算,导致中间电压值与设计值产生偏差,离线误差校准数据不能直接反映实际工作误差情况。为定量分析周围电场对CVT误差产生影响程度,以500 kV电压等级CVT实际参数建立有限元电场分析平台,开展金属支架、避雷器、高压引线产生的电场对CVT误差影响程度仿真分析计算,结合仿真试验对仿真结果进行验证分析。通过分析比较仿真数据与实测数据可知,外电场仅对CVT的比值差产生影响,周围设备导致的电场增加时会导致CVT比值差增加,高压引线夹角、长度、直径改变后对CVT比值差的影响在0.05%以内。该结论对开展CVT离线误差试验数据分析提供技术支撑。更多还原

【Abstract】 The capacitive voltage transformer(CVT)in operation is affected by the electrical filed of generated by the surrounding equipment due to its open type structure design. The participation of externally generated stray capacitance in the voltage division ratio of the capacitor unit leads to the deviation between the intermediate voltage and the design voltage and the offline error calibration data cannot directly reflect the actual operation error. In order to quantitatively analyze the influence extent of the surrounding electric field on the error of CVT,a finite element electric field analysis platform is established with the actual parameter of 500 k V CVT so to develop the simulation and analysis calculation on the influence extent of electrical field generated by the metal bracket,lightning arrester and high voltage lead on the error of CVT.Then,the simulation result is verified and analyzed in combination of real type test. Finally,it is known by analyzing and comparing the simulation data and actually measured data that external electrical field only affects the ratio difference of CVT and the electrical filed increase due to the surrounding equipment will lead to the increase of ratio difference of the CVT. The influence of variation of high voltage lead in the included angle,length and diameter on the ratio difference of the CVT is within 0.05%. This conclusion provides technical support for the analysis of CVT offline error test data.更多还原