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Mohamed Younes E. Henna ¹, Sayed A. Nagy ², Ahmed Fahmy M. Bendary ³, Hasan M. Moustafa ⁴

Affiliations
1 Ministry of Electricity and Energy, EG
2 Department of Electrical Power Engineering, University of AlAzhar, EG
3 Helwan University, EG
4 inistry of Electricity and Energy, EG

Abstract

This paper has developed the superconducting magnetic energy storage (SMES) unit to improve the power quality and transient stability behaviour of a large industry facility in a smart grid. The connected transmission line with the utility has tripping system by using the under frequency relays, this tripping system has been modified to prevent cascaded collapse of the power system in case of occurrence of utility power system external fault. Fault simulated has been performed to explore the accuracy of the transient stability analysis. To improve the power quality, SMES unit has been installed in the smart distributed system. The sensitivity analysis of SMES unit is applied to achieve better system responses. SMES unit with frequency changing as feedback signal to active power control is also used to improve the electric power fluctuation and help the utility in maximum demand times. Also improve the power quality of the system and reduce the economic losses of the facility.

Keywords

Smart Grid, Superconducting Magnetic Energy Storage, Transient Stability, Power Quality.

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Mohamed Younes E. Henna ¹, Sayed A. Nagy ², Ahmed Fahmy M. Bendary ³

Affiliations
1 Ministry of Electricity and Energy, EG
2 Department of Electrical Power Engineering, University of AlAzhar, EG
3 Electrical Power and Machine Department, Helwan University, EG

Abstract

This paper presents a new method to prevent cascaded events of pilot distance relays caused by zone 3 elements in case of heavy loaded transmission line or during load encroachment by using logic controls. Undesired operation of distance relay may be leaded to activation of another distance relays and cascaded to partial or total blackout in the end. A proposed adaptive distance protective gives a new concept to distinguish between faults and heavy loaded transmission line depending on analyzing system parameters and data transfer between distance devices, and also secures time to make repaired action like load shedding. Logic controls are used to insure the decision to trip or not, through observing the system parameters and compare its values with setting already input to the system. When the distance relay pickup and the logic controls find the system is healthy, that means the resulted pickup came from transmission line overload not from actual fault. Consequently the trip signal is blocked and protects the system from cascaded mal-operation, or send load shedding signal to reduce the current flow through this line.

Keywords

Stance Relay, Cascaded Events, Logic Control, Load Shedding.

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Mohamed Younes E. Henna ¹

Affiliations
1 Operation Department, Ministry of Electricity and Energy, EG

Abstract

This paper has developed way to secure substation operation though modified the busbar protection, and make it more reliable, accurate and independable. Mal operation of busbar protection is a very critical situation leading the entire substation out of services and consequently the power station units and load feeders which connected with it. Positions of the isolators are the main part in busbar protection, so when the busbar protection lose one of the isolator position it mean that busbar protection cannot defined which busbar it is really connected with, to do the calculation and the action. In this paper we modified method to solve this problem by using algebraic algorithm and logic circuits to determine the isolator position and insure the trip dissection of the busbar protection.

Keywords

Substation Protection, Busbar Protection, Logic Circuits, Isolator Problems.

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