Experimental Simulation Of Disturbance Voltage On Secondary Cable Due To Ground Potential Rise In Power Substation

The main transient electromagnetic disturbance sources in power substation include switch operation,lightning impulse and short circuit fault,which cause ground potential rise and transient enclosure voltage.The transient potential rise maybe coupled to the secondary equipment port via the ground network and the cable shielding layer,and potentially affects the normal operation of the secondary equipment.Therefore,it is of great practical value to master the disturbance characteristics of transient potential rise of the secondary equipment port.At present the two main methods of analyzing the disturbance of secondary equipment port by transient ground potential rise are field measurement and modelling simulation.On the one hand,field measurement can not fully reflect the various influencing factors and change law because of not being able to change the basic experimental conditions generally and not being allowed to do enough experiments.On the other hand,the accurate modelling of the disturbance voltage induced on the port of secondary equipment resulted from ground potential rise is very difficult due to the following reason: the complexity of practical configuration,the variety of influencing factors,and the uncertainty of some input parameters.Consequently,it is highly valuable to carry out experimental simulation which can change the experimental conditions and has unrestricted number of experiments.This paper designs and builds an experimental platform for simulating the disturbance voltage of the ground potential rise on secondary cable in power substation,and carries out the experimental simulation study of the influencing factors and disturbance law of disturbance voltage of ground potential rise on secondary cable based on this experimental platform.Selecting the termination load,different types of excitation source,bellows connection situation and cable routing situation as the simulated experimental condition,we conducted hundreds of experiments,measured and obtained the disturbance voltage waveform data of interference between the core wires,core-to-ground and core-to-shielding layers with different grounding modes of the shielding layers under different conditions.Finally,conclusion was got about the influencing factors and disturbance law of ground potential rise on secondary cable by comparison and analysis of the experimental data.,Which can be used as a reference for the design of protective measures against disturbance voltage of ground potential on secondary cable.