PPT FINAL YEAR PRESENTATION ON SUBSTATION PROTECTION .pptx

PRESENTATION ON SUBSTATION PROTECTION DEVICES

1. SEMINAR PRESENTATION ON “SUBSTATION PROTECTION DEVICES” Presented by: PRINCE KUMAR ROLLNO- 2021031164 3 RD YEAR (SEC-B) ELECTRICAL ENGINEERING MADAN MOHAN MALVIYA UNIVERSITY OF TECHNOLOGY

2. Contents Introduction Protection devices Protection requirement Current transformer(CT) Potential transformer(PT) Relay Circuit breaker Lightning arrester Isolators Conclusion

3. Introduction Substation Protection system Power System-Protection is a branch of electrical power engineering that deals with the protection of electrical power systems from faults through the isolation of faulty parts . A typical substation

4. Why Do We Need Protection The objective of a protection scheme is to keep the power system stable by isolating only the components that are under fault, whilst leaving as much of the network as possible still in operation. Under abnormal working condition protection is necessary for safety of electrical equipments and safety of human being.

5. Switchgear And Protection Devices What are the Protection devices ? The apparatus or equipments and their associated auxiliaries employed for controlling, regulating and switching on or off the electrical circuits in the electrical power system is known as “Protection devices” or “switchgear” . Protection devices protect the transmission lines, generators, transformers and other electrical equipments from various “faults” .

6. Three-Phase Diagram of the Protection

7. Components of switchgear Current Transformer Potential Transformer Relays Circuit breakers Lightning arresters(or “Surge diverter”) Isolators(or “Disconnecting switch”) Fuse

8. Current Transformer(CT) A current transformer ( CT ) is used for measurement of alternating electric current. When current in a circuit is too high to apply directly to measuring instruments, a current transformer produces a reduced current accurately proportional to the current in the circuit, which can be conveniently connected to measuring and recording instruments. Current transformers are commonly used in metering and protective relays in the electrical power industry.

9. Current Transformer contd…

10. Potential Transformer(PT) Potential transformers (PT) (also called voltage transformers (VT)) are a parallel connected type of instrument transformer. They are designed to present negligible load to the supply being measured and have an accurate voltage ratio and phase relationship to enable accurate secondary connected metering. It gives the reference voltage to the Relay for Over Voltage or Undervoltage protection.

11. Potential Transformer contd…

12. Introduction To Relay A Relay is a logical elements which process the inputs(mostly voltage and currents) from the system and issue a trip decision if a fault within its jurisdiction is detected. Inputs to the Relays are Current from current transformer(CT) Voltage from voltage transformer(VT)

13. Circuit Breaker(CB) Circuit breakers are an automatically operated electrical devices, design to close or open contact members, thus closing and opening an electrical circuit under normal or abnormal conditions. It operates on relays command. It handles the large voltage and current. A circuit breaker consists of two contacts namely “fixed” and “moving contacts” which touches each other under normal condition i.e. when circuit breaker is closed.

14. Circuit breaker contd… An Oil Circuit Breaker SF 6 Circuit Breaker

15. Lightning arrester(Surge Diverter) The device or equipment used for the protection of the power system against voltage surge is called “surge diverter” or “lightning arrester”.

16. Isolators Isolators are used to isolate the high voltage from flow through line into the bus. It allows only needed voltage and rest is earth by itself if required. Isolator

17. Conclusion The objective of the protection devices(system) is to keep the power system stable by isolating only the components that are under fault, while leaving as much of the network as possible. Now a days the Substation Protection System is fully automatic.

18. References Power system protection and switchgear by Badri Ram TMH publication. Fundamentals of Power system protection by Yashwant G. Paithankar, S.R. Bhide. Electrical Power system by A Wright. Wikipedia

19. Thank you...