DEVU ppt on generator protection

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Transcript of DEVU ppt on generator protection

SUBMITTED BY: GUIDED BY: DEVESH KUMAR BAGHEL Mrs. SUMAN PURI (B.TECH, VII SEMESTER) Head of the department FINAL YEAR Department of Electrical Engg ELECTRICAL ENGG. DEPTT.

KOTA SUPER THERMAL POWER PLANT IS A COAL BASED

STEAM POWER PLANT

IT IS LOCATED ON THE LEFT BANK OF RIVER CHAMBEL.

TOTAL GENERATION CAPACITY IS 1240MW.

CENTRAL ELECTRICAL AUTHORITY WAS PREPARED THE

PROJECT OF THIS PLANT IN APRIL,1973.

INTRODUCTION

GENERATION CAPACITYGENERATION CAPACITY

1.Turbine1.Turbine

2.Generator 3.Transformer

4.Coal Handling Plant

5.Ash Handling Plant

6.Electro-Static Precipitator6.Electro-Static Precipitator

7.Water Treatment Plant

8.Feed water plant

9.Condenser

10.Primary Air fan

11.Induced draft fan

12.Forced draft fan

13.chimney

EQUIPMENTS FOR STEAM GENERATION

BOILERECONOMISERSUPERHEATERFURNANCEAIR-PREHEATERREHEATER

The "Wild"PowerSystem

G

Exciter

Loss of FieldLoss of Field

Overexcitation

Overexcitation

Overexcitation

OpenCircuits

Loss ofSynchronism

InadvertentEnergizing,Pole Flashover

AbnormalFrequency

AbnormalFrequency

BreakerFailure

ReversePower

OverPower

• Percentage differential protection.• Protection against stator inter-turn faults.• Stator-overheating protection.

• Field ground-fault protection.• Loss of excitation protection.• Protection against rotor overheating because

of unbalanced three-phase stator currents.

• Overvoltage protection

• Overspeed protection

• Protection against motoring

• Protection against vibration

• Bearing-overheating protection

• Protection against auxiliary failure

• Protection against voltage regulator failure

• This protection is used for generators above 1 MW rating.

• It is used to protect against winding faults.

• It do not works fort external faults and overloads.

• Generator and transformer is considered as a single unit .

• percentage differential protection is applied for combined unit.

• Harmonic restrain is not provided in transformer.

Overheating of stator is caused by failure of cooling system, overloading or core faults.

Two methods are used for detection of overheating:-

1.By compairing the inlet & outlet temperature of cooling medium.

2.By using temperature sensing elements.

• The field winding on rotor is ungrounded then operation of generator does not affected during single ground fault.

• The incidence of second fault would cause serious damage.

• The unbalanced condition may arise due to following reasons:-

1.When a fault occurs in the stator winding.

2.An unbalanced external fault which is not cleared quickly.

3.Open-circuiting of a phase.

4.Failure of one contact of the circuit breaker.