Effect of Inverter Fed Drives on Rotating Machine Insulation

Postponed Virtual

$150.00 USD

Please join us for our virtual training course “Effect of Inverter Fed Drives on Rotating Machine Insulation”

The Course will run North American Eastern Standard Time (EST) from 10:00 AM to 3:00 PM with a break from 12:00 PM to 1:00 PM

Cost: $150.00 USD

Many motors are powered from inverters which facilitate improvements in process efficiencies.  One of the most common drives now being used is of the voltage source, pulse width modulation (VS-PWM) type.  Such drives generate high voltage spikes in the kV range with risetimes in the sub-microsecond range.  These high voltage spikes are a form of severe electrical interference which can make the detection of partial discharge (PD) (with magnitudes 1000 x smaller) difficult, due to the overlapping frequency content in PD and the spikes.  This course will describe the basic insulation problems caused by such drives, qualification methods for stator winding insulation subject to repetitive voltage surges and outline the challenges in measuring PD on operating motors fed by VS-PWM drives.



The webinar is directed at engineering and maintenance personnel who purchase, test, maintain, and/or repair high voltage rotating machines. Consultants, manufacturers and repair shop personnel are also welcome.


Dr. Howard Sedding is currently employed by Qualitrol Iris Power – Qualitrol as an Insulation Engineer. He has been involved in, or responsible for numerous projects related to the specification, testing, monitoring and maintenance of solid, liquid and gaseous electrical insulation systems in all of the major items of high voltage equipment. He has over 100 publications in technical journals and conferences in the above fields and has taught courses on rotating machines and cable testing and condition assessment.

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