Partial discharge testing is one of the most effective ways of detecting errors in the insulation system for electrical assets before a breakdown or any significant damage can occur. In this blog, we’ll be taking a look at three things you need to know about partial discharge testing.
It Monitors Trends In Activity
Partial discharge testing online permits trends in activity to be monitored over time. While partial discharge is created by high-voltage stresses, it can also be influenced by other ambient and operating stresses, such as humidity, temperature, and load. Due to the fact that partial discharge activity usually occurs well before insulation failure, by monitoring and analyzing the partial discharge over time, you can make strategic decisions regarding renewal and refurbishing programs, such as the ordering of key elements with long lead times. It usually isn’t necessary to replace an asset that is slightly older if it is serviceable, so the cost of replacement can be postponed via maintenance.
It Can Be Done Quickly And Efficiently
Partial discharge monitoring and testing are particularly critical when the high or medium voltage asset is essential to a network’s operation. This could be due to financial consequences that have occurred as the result of a failure, limited network redundancy, the age of the asset, or past failures. Identifying partial discharge within an entire network can be achieved easily and quickly using High Voltage Partial Discharge technology to indicate that there are impending insulation faults early on.
Medium voltage and high voltage plants that can be monitored or tested include capacitors, current and voltage instrument transformers, rotating machines motors and generators, dry type and oil-filled transformers, bushings, power transformers, switchgear, cables, and cable accessories such as sealing ends, joints, and terminations.
It Requires Highly Sensitive Equipment
Because partial discharge activity emits low magnitude signals, it is essential to use extremely sensitive partial discharge measuring equipment. However, this can lead to increased susceptibility to electronic noise, which can make it tricky or even impossible to locate or detect partial discharge signals. In order to detect partial discharge signals successfully, this interference needs to be eliminated.
While some partial discharges can cause significant damage to the function of the insulation system, other forms of partial discharge may have a slower effect of degradation. In electrical machines that rotate, such as generators and motors, there are a number of different sources of partial discharge present in the system simultaneously. One of the most important functions of modern digital partial discharge systems is to filter out noise and separate partial discharge signals that overlap. This function is essential for effective partial discharge testing so that any elevated or damaging partial discharge levels can be differentiated from regular partial discharge activity without any interference.