A decoupling method of contactless electric field measurement for railway catenary

The transient over-voltage in the railway network will endanger the normal operation of the railway. The contactless electric field sensors can measure it flexibly and conveniently and plays an important role in analyzing the characteristic parameters of the overvoltage and designing the insulation coordination of the railway. While in contactless measurement of two-phase voltage, the electric field measured by the sensor placed under the line is the coupling electric field produced by two-phase conductors with different proportion coefficient. Therefore, a decoupling method of contactless electric field measurement for railway catenary is proposed. Through this method, the proportion coefficient of electric field generated by each phase conductor at each sensor can be calculated, and the two-phase voltage can be inversely deduced from the measured two-phase electric field signal. Finally, the voltage measurement test is carried out in the traction substation. The research results can provide guidance for contactless voltage measurement of traction power supply catenary.