Session two of a four part series, helps the audience to better understand the concepts of electrical clearance, the calculation of BIL, BSL, and insulation coordination. Most substations are located in fenced-off areas above ground. In cities substations may be constructed in buildings or underground. Energized conductors and connecting buswork within a substation or switchyard are usually bare (non-insulated) and are installed on insulators that provide insulation from the ground. Insulation from other energized and grounded objects is provided by proper air distances (clearances). Sufficient clearances among ground and various energized air-insulated equipment are required to prevent (minimize the probability of) sparkovers and flashovers which would disrupt the operation and integrity not only of the affected equipment but also of the entire or large parts of the electric power system. IEEE Std 1427-2020 “IEEE Guide for Recommended Electrical Clearances and Insulation Levels in Air Insulated Electrical Power Substations” provides the required information.

Presenter bio:
Dr. George Gela, LSMIEEE, An internationally recognized electric utility expert with a doctoral degree in electrical engineering and an extensive background in research, testing, and teaching. Delivered invited presentations on worldwide experience in live work in China and Australia as part of Marcus Evans's training seminars.

Mr. Ma is an Electrical Engineer and Technical Expert in the Transmission & Distribution Division of Burns & McDonnell. He has thirty years of experience in substation engineering in the power delivery industry. Mr. Ma has been an IEEE PES member since 2006. He currently serves the roles of the vice chair of the IEEE PES Substation Committee Electrical Substation Design Subcommittee (SCD0), Vice-chair of Working Group D2 and Chair of Working Group D1 (AIE Clearance & Insulation Levels). Mr. Ma is professionally licensed in Alberta, Canada (P.ENG) and Wisconsin, USA (PE).