- Calculation of three phase faults using Ohmic method
- Per unit method for simplifying fault current calculations
- Worked-out example using per unit method— 3ph, ph-ph, and ph-ground
- Typical values of per unit impedances for generators, motors, transformers, etc.
- Basic concept of symmetrical components and using them to calculate fault currents
- Fault current relationship involving different transformer connections
- Worked-out example using a commercial software
- Symmetrical and unsymmetrical components of fault current
- What is DC offset?
- Response of relays to DC offset
- Relay response depends on time elapsed since fault inception
- Fault current duties experienced by interrupting devices such as fuses, breakers, etc.
- Evaluation of interrupting devices based on first cycle duty and symmetrical duty
Ed Khan has been with Doble for over 6 years working in various capacities including product manager for protection tested related instruments. Currently, he is the Director of Protection R&D and Training at Doble.
Prior to Doble, Mr. Khan has worked for GE, ABB, SEL, KEMA and others in various capacities. He has 33 years of experience in system studies, protection applications, relay design, teaching and product management. He has a thorough knowledge about product development, protection, harmonic analysis, harmonic filter design, stability studies, Real Time Digital Simulations and more. He has presented courses on behalf of Doble in US and overseas and has been an invited speaker for utilities and industrial customers in Southeast Asia, Middle East, Mexico, India and China.
Katherine George is a Training Specialist and has been with Doble for over two years. She provides customer training and consulting services for implementing and using RTS software. In addition, Ms. George is responsible for maintaining and updating the RTS User Guides and training materials. Before joining Doble, she was a professional services consultant and trainer with TMA Systems, where she was responsible for customer implementations, training and database management.