Research On Comprehensive Test System For Power Cable Failure

With the rapid development of national economy,electric energy plays an important role in the life of residents and industrial production.Power cable is an important carrier of electric energy.Due to the rapid development of urban and rural construction,it is necessary to change the complex ground cable into buried cable,which can beautify the environment and save space.However,it will cause power failure due to the fault of buried cable,which brings great inconvenience to industrial development and residents’ life.Therefore,it is of great practical significance to quickly and effectively locate the cable fault point.This paper first introduces the development status of the test system at home and abroad,and then describes the principle of cable fault detection.Finally,aiming at the problems such as high price of imported products and difficulties in later maintenance,a set of comprehensive test system for power cable fault is designed based on cable fault detection technology.The system is used for preliminary judgment,positioning and fault diagnosis of power cable the test software can automatically identify the reflected waveform and display the cable fault distance,which really makes the cable fault test have the advantages of light,simple,efficient and safe,and provides convenience for the rapid test of power cable fault.The system is composed of insulation test unit,high frequency and high voltage power supply unit,multiple pulse generation unit,fault test unit and path test unit.The lowvoltage pulse method is used to locate the low resistance fault of the cable,and the multiple pulse method and the impulse current method are used to locate the high resistance fault of the cable.Among them,the insulation test unit is mainly used to determine the fault type;the high-frequency and high-voltage power supply unit is used to collect the reflected waveform;the multiple pulse generation unit is used to guide the high-frequency and highvoltage pulse to the cable fault phase;the fault test unit is used to locate the cable fault distance;and the path test unit is used to find the cable path.According to the design requirements and functions of cable fault location,under the simulated real cable fault environment,the experimental results show that the positioning function of the test system is accurate,the fault test unit can automatically identify the reflected waveform and display the cable fault distance,which meets the test accuracy requirements within ± 2% of the system,and achieves the expected design goal.