Fabian Oettl is the product manager for rotating electrical machines testing and monitoring at OMICRON. We asked him recently about his job, the importance of machine testing and current trends, as well as how OMICRON solutions help engineers daily with the assessment of machine condition and reliability.
Why is the regular electrical testing of rotating machines so important?
FO: During factory acceptance testing (FAT) and commissioning, electrical testing verifies the material and performance quality of machines. For utilities and at industrial plants, electrical testing and PD monitoring help engineers to avoid costly unplanned outages, as well as to manage resources and plan maintenance periods more efficiently for in-service machines. Lastly, service providers rely on electrical testing and PD monitoring to verify whether machine repairs were performed successfully and to ensure long-term stability.
Are there any specific trends that are driving the importance of rotating machine testing?
FO: The market has experienced an increase in testing and PD monitoring during the past decade. This is due in part to the fact that the in-service behavior of the machines has changed. For example, an increasing amount of starts and stops per year exposes machines to a higher stress level than they were designed for. Additionally, machines have been economically streamlined to such a degree from a thermal, electrical and mechanical point-of-view. There is very little buffer should something go wrong. Last but not least, operators are moving from a time-based maintenance to a more optimized condition-based maintenance.
What types of tests is OMICRON focused on for rotating machines?
FO: We are focused on the electrical testing of the winding and the winding insulation for both stators and rotors in motors and generators. This ranges from a simple winding resistance test to capacitance and dissipation/power factor measurements as well as more complex partial discharge (PD) analysis and beyond.
On which types of rotating machines are these electrical tests performed?
FO: In principle on every machine. Starting from low-voltage motors up to the biggest hydro generators with an inner diameter of higher than 15 meters or even nuclear power plant turbo generators with a nominal voltage up to 27 kV. Testing of high-voltage industrial motors has become more and more important too, as an unplanned outage of such machines stops the whole manufacturing line they are a part of.
Read the whole interview