What is the Partial Discharge (PD) testing methods ?

Partial discharge (PD) testing is a method used to detect and diagnose PD in cable systems. The objective of PD testing is to identify any potential issues with the cable insulation system, such as defects, damage, or degradation, before they become a major problem. There are several methods of PD testing, including:

Ultra-High Frequency (UHF) detection: This method involves the use of UHF sensors, which are installed at strategic locations within a cable system, such as at cable terminations or splices. These sensors detect the electromagnetic emissions generated by PD, which can be analyzed to identify the specific location and cause of PD.

PD current measurement: This method involves measuring the PD current flowing through the cable insulation system. This can be done using a PD current probe, which is placed around the cable to measure the PD current. By measuring the PD current, it is possible to determine the magnitude and location of PD within the cable.

Acoustic PD detection: This method involves listening for PD using an acoustic sensor. PD generates sound, which can be detected by an acoustic sensor and analyzed to determine the location and magnitude of PD within the cable.

Thermal imaging: This method involves the use of a thermal imaging camera to detect the heat generated by PD. Thermal imaging can detect PD that is not visible to the human eye, and can help to identify the location and magnitude of PD.

PD voltage measurement: this method involves measuring the PD voltage across the insulation system, which can be performed with a PD voltage probe. By measuring the PD voltage, it is possible to determine the magnitude and location of PD within the cable.

The results of PD testing can be used to identify the specific location and cause of PD, and to develop a plan for addressing any issues that are found. PD testing is an important part of maintaining the reliability and safety of cable systems, as it can help to detect and diagnose PD early, before it causes significant damage.