Equipment operated in the electric power system are of high value and it is crucial to ensure the safe operation of these devices. High-cost failures can be caused by the unexpected errors of the system equipment.
The most sensitive part of the electrical equipment is the electrical insulation. Diagnostic of the plastic insulated cables is dealt by my master's thesis
The purpose of the diagnostic examination of the electrical equipment is to implement a series of tests – preventing malfunctions or failures, or at least reduce their number – which would minimize the operational costs.
The degradation process of the plastic insulated cables and the main diagnostic methods were discussed in the first part of my thesis.
Two main measurement methods were presented, which are based on return voltage measurement: the voltage response (VR) and the recovery voltage (RVM) measurement methods. I also explained the most common insulation diagnostic procedure: the measurement of insulation resistance (IR).
I used the VR and the IR methods to measure the electrical properties of the new and thermal aged PVC and polyethylene insulated cable and I analyzed the aging of the cable insulation based on the measurement results.