Underground cable fault tester design and application

In this research, dismantling the entire cable line for the detection of faults in cables laid underground causes time and cost losses for the user and the manufacturer. The occurrence of this situation necessitates knowing the exact location of the fault on the cable. The importance of this study is to provide time and cost savings by determining the location of the fault in the cable without the need for dismantling the cable line. The aim of this thessis is to design a pulse generator that can provide high voltage and energy in order to determine the location of faults such as insulation weakness, leakage current, short circuit that may occur in medium voltage cables that are lowered underground. It is the design of the electronic hardware of the device that can provide high voltage and energy to the transmission line, providing the device control with software design and production with the mechanical structure. In order to detect the fault location, it is based on this energy, which is given by applying high voltage to the transmission line, to ensure arc formation in the faulted area on the line and to listen to the sound caused by the arc by listening with sensitive headphones. The designed device is fed from the network or from the inverter in battery systems, and the supply voltage is increased to 8kV with transformer and voltage doubling circuits. This increased voltage is stored in high capacitance and voltage level capacitors, and thus the energy level is provided up to 10000 joules according to the voltage level. In order to facilitate the use of the device, an nRF module was added to the device, enabling the device to communicate with the control unit designed for the user. The control unit is designed to be able to remotely control the device with a diameter of 2 km. Unlike equivalent cable fault detection devices designed for the same purpose, it has been possible to increase the service life of the device, to reduce device maintenance costs, labor and cable maintenance/repair costs, with hardware that can remotely control the device. As an output, the device has been completely produced and presented to the market. The arc voltage, which is presented as 8kV in this study, can be made more comprehensive by extending the distance of the fault detection line, thanks to the increased voltage with the addition of options such as 16kV, 32kV in future studies. By increasing the fault detection line length, the communication distance of the remote control provided by the user can also be increased. In addition, software arrangements such as the echo algorithm that can be added to the control unit and the hardware that supports these software can be added, and the earphones used in the detection of arc sound can be removed.