Extra high voltage transmission of forth semester electrical diploma

EPT PPT

1. EXTRA HIGH
VOLTAGE
TRANSMISSION

2. EXTRA HIGH VOLTAGE
TRANSMISSION
EHVAC Transmission line is Necessary because using EHVAC
transmission line
1)Voltage drop (V=IR) in the line is less.
2) power loss ( I²R) due to resistance is less.
3) Transmission efficiency is more.
4) Voltage regulation is better.
6) small conductor required. Size is
overall System Performance is improved.
Reliability of the System is improved.
8) Good economy i’s achieved.
8) power transmission capacity of the Power System is improved. Because capacity of line (Voltage)

3. EXTRA HIGH VOLTAGE
TRANSMISSION
▪HIGH VOLTAGE SUBSTATION COMPONENTS.
1.Busbar
2.Surge Arregter(Lightening Arrester).
3.EarthingSwitch
4.Circuit Breaker
5.Current Transformer (CT)
6.potential transformer (PT)
7.Power Transformer.
8.shunt reactor
9. shunt reactor
10. shunt capacitor.
11. Series capacitor
12. Switch gear
13. station earthing System.
14. series reactor

4. 1. BUSBAR:
▪Busbar is a conductor used to receive power from generating station incoming circuit) and to deliver
power to load (distribution Station / outgoing circuit).
▪Busbar may be red type, tubular type circular type or strip type.
2. SURGE/LIGHTENING ARREGTER:
▪Surge arrestor or lightening arrestor(LA) is a device used to arrest the lightening stroke and
discharge the over voltage surge to earth..
▪It is connected between phase conductor and earth, it is algo connected near the terminal equipment.
EXTRA HIGH VOLTAGE
TRANSMISSION

5. 3. ISOLATOR
▪Isolator is an air operated switch used during maintenance purpose. It provide isolation for live
conductor’s for mainte- -nance purpose.
▪It is located on both sides of circuit breaker (C.B)
Types
1. single break
2.double break
4. CIRCUIT BREAKER (CCB)
A device used to make and break the ciscuit under normal and abnormal (Fault)condition manually
or automatically.
▪ It is located on both sides of protection
EXTRA HIGH VOLTAGE
TRANSMISSION

6. 5. POWER TRANSFORMER
▪ A Static device used to Step up the voltage for transmission purpose and to sen down the
voltage for feeder line
▪ It is located at receiving station and generating station
Types
1.Delta- Desta
2. SF6 & oil cooled
EXTRA HIGH VOLTAGE
TRANSMISSION

7. 6. SHUNT REACTOR
▪ A deviec which use to absorb reactive power.
▪It is located at the center and load of transmission lines.
Types
1.Air cooled
2.Oil cooled
EXTRA HIGH VOLTAGE
TRANSMISSION

8. 7. CURRENT TRANSFORMER
▪A device which use to step down the current for measurement, protection and control
purpose.
▪It provide supply to the relay and breaker’s for it’s operation
Type
1.Toroidal CT
2.Bar type CT
3.Wound CT
EXTRA HIGH VOLTAGE
TRANSMISSION

9. 8. POTENTIAL TRANSFORMERS
▪A device used to step down the voltage for measurement, protection and
control purpage.
▪It provide supply to the Relay and breaker for it's operation.CT and PT is
located near the protection Zone for measurement & control purpose.
Types
1)Elecheomagnetic PT
2)capacitor PT
3)optical PT
EXTRA HIGH VOLTAGE
TRANSMISSION

10. 9. CIRCUIT BREAKER
▪A device uged to make and break the circuit under normal and abnormal (fault) condition
manually or automatically.
▪It is located on both sides of protection zones.
Types
1. Air C.B.
2. Oil C.B.
3. Air blast C.B.
4. SF6 C.B.
EXTRA HIGH VOLTAGE
TRANSMISSION

11. 10. EARTHING SWITCH
▪Earthing switch dis provide path for the high voltage Leakage / short circuit current) to the
ground.
▪It is mounted on the igolator frame.
Types
1.TEC
2.TEB
EXTRA HIGH VOLTAGE
TRANSMISSION

12. ADVANTAGE OF EHV TRANSMISSION LINE.
1)Voltage drop in the line is less.
2) line current is less.
3)power Loss in the line is less.
4) Transmission efficiency is more.
5) Voltage regulation is better.
6)Small conductor size is required.overall gygtem performance is improved.
7)Reliability of the system is improved Good economy is achieved.
8)power transmission capacity of the system is improved.
EXTRA HIGH VOLTAGE
TRANSMISSION

13. LIMITATION OF EHV TRANSMISSION LINE
1.High corona Loss.
2.Increased radio interference.
3.tower structure (height) and insulation cost is increase.
4.cost of switchgear equipment is increase.
5.Increased electrostatic effect.
6.tower structure size is more.
7. proximity and skin effect 19 more.
8.power flow can not be control easily.
9.Short circuit current level is increage
10. require intermediate substation.
EXTRA HIGH VOLTAGE
TRANSMISSION

14. APPLICATION
1.Long distance high power transmission
2. H-V primary transmission.
3.over head high power transmission.
4. Inter connected grid Ac power transmission.
EXTRA HIGH VOLTAGE
TRANSMISSION

15. Thank you