ABB Motor will explain to you how to solve partial discharge problems?

Date:2021-09-17 18:58:30

More and more users are making clear demands for low partial discharge when requesting high-voltage motors and generators. However, this is not an effective method to solve partial discharge, which can lead to higher costs and over design, but may not necessarily ensure longer service life or higher reliability.
The key roles of design, materials, and craftsmanship
At ABB, we will introduce Micadur ® Compact Industry and Enduraseal ® The insulation system is used for the stator winding of high-voltage motors and generators. Under normal operating conditions, the insulation system will withstand partial discharge throughout the entire service life of the equipment and requires regular maintenance to control partial discharge. Since the mid-1970s, we have used these insulation systems to manufacture tens of thousands of electric motors and generators, and have not experienced any failure accidents caused by partial discharge to date.
The quality of insulation system design and process, as well as the selection of materials, play a central role in determining the degree and impact of partial discharge activity.
Therefore, the first step in solving partial discharge must be done before ordering an electric motor or generator. This includes choosing the appropriate manufacturer. Choosing a manufacturer with a good reputation, reliable quality, and extensive experience will help ensure that there are no issues with partial discharge.
Detecting and measuring partial discharge
We also need to consider partial discharge measurement and discharge degree tracking, as measuring partial discharge can reveal many issues that are difficult to detect by other methods. However, as is well known, a single partial discharge measurement is difficult to directly evaluate. A better solution is to start regular measurements from the first identification test of the new winding to obtain trend data.
Compared to measuring only partial discharge, at ABB, we adopt a more comprehensive method - ABB LEAP (Expected Life Analysis Program), which is a regular inspection that measures partial discharge and combines it with other measurement results to evaluate the remaining life of stator winding insulation. In addition, conducting a visual inspection is also an effective monitoring method. But partial discharge measurement requires a certain investment and may also require special hardware.
Is it meaningful to specify a low level of partial discharge
For factories that are unwilling to invest in partial discharge testing, our suggestion is to use motors or generators with a longer expected lifespan. Reliable manufacturers ensure that their standard products are designed and manufactured to withstand partial discharge. ABB motors and generators have stronger insulation systems and longer service lives, and will provide additional "safety margins" and longer operating times.
In contrast, we do not recommend specifying lower levels of partial discharge during the procurement process. This inevitably leads to higher costs and often fails to produce ideal results. This is because there is no direct relationship between partial discharge value and insulation life. For specific motors or generators, electrical stress is likely not the main factor causing insulation aging. In any case, 'low' partial discharge does not mean anything, as the absolute value of a single partial discharge measurement is very difficult to evaluate.