Grid Innovations

Faults (Short Circuits) & Football Players

Jan. 11, 2016

Whether you work in a utility, a solar firm or you are a resident who lost power, you probably heard someone mentioned the word “fault” or “short circuit” before.

Ahmed Mousa

Whether you work in a utility, a solar firm or you are a resident who lost power, you probably heard someone mentioned the word “fault” or “short circuit” before; from the utility perspective, we design the system to withstand a certain fault current level; from a solar perspective, the discussion whether solar contributes to the fault or not is common and from a customer perspective, they probably lost power before due to a fault on the line (Mother nature to blame).

What is a fault? Fault is simply an “unwanted” flow of large amount of current (thousands of amperes, where, ampere is the unit of measuring electric current) from various sources to the fault location (i.e. the location where a tree branch fell on the distribution lines or the location when a construction worker dug thru utility cables). Voltage is the potential difference; at the fault location, the voltage is around zero, thus all nearby generators, transformers, etc. sees the zero electric potential and send “contribute” large amount of current to the fault location.

In summary, think of a fault location as a football player in the final game (Super Bowl) running as fast as he can toward the touchdown, with only few seconds left in the game; that player represent the zero electric potential; all the players in the other team will do their best to stop that player, thus sprinting to the tackle, all the players are directed to one specific location with one goal to reach that player as fast as possible and to produce damage (stop him from scoring a touchdown).

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About the Author

Ahmed Mousa | Principal Engineer/Adjunct Professor/Board Member/Founder & CEO

Ahmed Mousa, M.S.E.E., has over 12 years of experience in transmission, sub-transmission, substations and distribution systems with industry leaders such as Consolidated Edison, PSE&G, PEPCO, and First Energy. He is a subject matter expert in transmission/sub-transmission, distribution and substation planning. Ahmed has years of expertise conducting PSS/E load flows, i.e. forced & scheduled outages analysis, phase angle studies, voltage analysis, network/non-network load transfers. Ahmed provides analysis and support during heat waves, storms and other system emergencies.

Mr. Mousa is an Adjunct Professor at New Jersey Institute of Technology (NJIT) teaching advanced topics graduate electrical engineering courses.

Mr. Mousa serves on the New Jersey Association of Energy Engineers board as a board member.

Mr. Mousa is currently the Principal Engineer at PSE&G in the Electric Delivery Planning section, where he is responsible for managing power system generation, transmission and distribution simulation studies, developing the short/ long range substation forecasts, analysis and load relief, performing short circuit studies, performing breaker duty analysis, developing transmission and distribution station and feeder designs, reviewing large customer demand proposals. Mr. Mousa is responsible for all Distributed Energy Resources technical evaluations and interconnection agreements.

Mr. Mousa is the Founder/CEO of The Electric Bridge Consulting firm assisting large and small utilities, colleges/universities & consulting firms by providing electric utility services, educational/training services, consulting services, leadership seminars, career consulting, lecturing services, electric professional engineering courses & national & international webinars.

Mr. Mousa was responsible for the short term, long term (1/5/10/20/30 years), and emergency planning for the area substation, transmission / sub-transmission feeders and the 4 kV system at Consolidated Edison. He has conducted several studies on the impact of electric vehicles, distributed generation, steam to AC conversion, energy efficiency models, and R&D initiatives on the distribution and transmission system.

Mr. Mousa was the project manager for a SCADA GE XA21 Energy Management System and the project manager and project engineer for President Obama’s Department of Energy stimulus grant for Consolidated Edison’s 4 kV system.

Awards include the 2009 3rd Quarter Distribution Engineering ALVA Award for 21st Century Leader, the 2012 “Sustain Energy Reliability” Team Award, and the 2013 Excellence in Design and Genius Engineer (EDGE) Award Nominee for “Developed Load Calculation Tools for System and Transmission Operations.” He has over eight years of experience in providing training in a wide range of subjects including PSS/E, 4 kV systems, distributed generation grid adoption, system operation outage analysis, transformer ratings, voltage studies, basic and advanced power flow, intermeshes, phase angle studies, capacitor bank impact on the grid, smart grid, plant information (PI), post contingency analysis, voltage reduction, and conservation voltage optimization. Mr. Mousa received his Bachelor's Degree in Electrical Engineering from Stony Brook University and later a Master's Degree in Electrical Engineering from Manhattan College and has completed the Siemens PTI Distribution and Transmission courses.