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Dr. Greg Stone

Greg Stone is an electrical engineer who graduated from the University of Waterloo, Canada in 1975. He subsequently obtained a Ph.D. in electrical engineering from the same school. From 1975 to 1990, Dr. Stone primarily worked for the Research Division of Ontario Hydro, at the time the largest electric power utility in North America, where he was involved with the testing of high voltage equipment such as motors, generators, transformers, GIS and power cables. From 1990 until his retirement in 2021, Dr. Stone was with Iris Power LP in Toronto, Canada, a company he helped to form. Iris Power LP designs, manufactures and sells on-line partial discharge test equipment for machines as well as manufacturing a wide variety of other on- and off-line condition assessment tools for motor and generator windings.

His research interests include the theory and practice of partial discharge measurement, diagnostic tests of all kinds to assess electrical insulation condition, and aging of electrical insulation under 50/60 Hz conditions as well as voltage impulses from converters.

Greg Stone has published over 200 technical papers, has been awarded 3 patents concerned with high voltage equipment testing, and has published three books. The most recent is "Practical Partial Discharge Measurement on Electrical Equipment" published by Wiley/IEEE Press in 2023.  He co-wrote the second edition of the Wiley/IEEE Press book “Electrical Insulation for Rotating Machines – Design, Evaluation, Aging Testing and Repair: Second Edition”, in 2014.

In the past he represented Canada on the International Electrotechnical Commission's IEC 2J Sub Committee (Rotating Machine Insulation), and later became its Chair. He continues to be active in IEC Technical Committees 2 (rotating machines), 42 (high voltage testing) and 112 (insulation). He has also chaired several IEEE committees that created standards for evaluation and testing of rotating machines. He is past President of the IEEE Dielectrics and Electrical Insulation Society; and was twice General Chair of the IEEE International Symposium on Electrical Insulation (now called the Electrical Insulation Conference). From 2006 to 2012 Dr. Stone was an elected member of the IEC Council Board, the IEC's governing body.

Amongst other honours, Dr. Stone was elected a Fellow of the IEEE in 1992, was awarded the IEEE DEIS Forster Distinguished Service Award in 1993 and was a recipient of the IEEE Third Millennium Medal in 2001. He received the IEEE DEIS Dakin Award for his development of on-line PD systems for machines. The Dakin Award is the highest technical honour the IEEE bestows in the field of electrical insulation. In 2008 he received the IEC 1906 Award. He received the 2011 CIGRE Technical Committee Award for his contributions to the CIGRE Rotating Machines Committee A1. In 2018 he received the IEEE Kaufman Award. He is also a Fellow of the Engineering Institute of Canada. Dr. Stone is a registered professional engineer in Ontario, Canada.