TOPIC

- Governing of Francis Water Turbine

Prepared by-SHUBHAM P.SADH,

Civil Engineering-5th sem,

H.J.D. Institute, Kera

CONVENTIONAL POWER

ENGINEERING Reference: Steam & Gas Turbine and Power Plant Engineering (Dr. R. Yadav), Conventional Power Engineering (B.L.Singhal)

11/15/2013Fig. (1) Governing of Francis Water Turbine

GOVERNING OF FRANCIS

WATER TURBINE

11/15/2013

The major components of the governor mechanism are as under:

1. Oil pump and oil sump

2. Relay or control valve

3. Servomotor or relay cylinder

4. Governor and linkage

5. Regulating ring

6. Regulating rod

GOVERNING OF FRANCIS

WATER TURBINE

11/15/2013

1. Oil Pump & oil sump :- The system requires an oil sump to store the oil and an oil pump to regulate the oil supply in the mechanism.

2. Relay or control valve:- Relay valve is a spool valve having 5 ports, it receives the pressurized oil from the oil pump which is diverted towards the servomotor cylinder and return back to the sump.

3. Servomotor or relay cylinder :- It is double acting cylinder which acts as hydraulic actuator. It forces the received oil into the oil sump with the help of displaced piston.

4. Governor & Linkages :- A centrifugal governor is used as the measuring element of the closed loop control system. It is driven by the turbine shaft. The sleeve of the governor is connected through linkages to relay valve. The movement of sleeve is transferred through the lever.

5. Regulating Ring :- It is a circular ring having guide vanes pivoted at a point through the levers and links.

6. Regulating rod :- It connects the regulating ring to servomotor.

GOVERNING OF FRANCIS

WATER TURBINE

11/15/2013

Working :- When Load is less, the centrifugal governor senses the speed and

valve V1 closes while V2 of relay valve opens which allows the high pressure oil to

enter the left portion of servomotor. This pushes the piston forward and partially close the passage of guide blades. [See Fig. (1) on slide no. 2]

- Reverse action is takes place when the load is more.

11/16/2013Regulating Rod

Regulating lever

Spiral CasingRegulating ring

Turbine Inlet

Regulating Shaft

Input fromServomotor

Guide Vanes

Fig.(2) Components of Governor mechanism of Francis Water Turbine

11/16/2013Guide Vanes

Regulating Rod

Regulating ring

Fig.(3) Components of Governor mechanism of Francis Water Turbine

THANK YOU

Prepared by-SHUBHAM P.SADH,

Civil Engineering-5th sem,

H.J.D. Institute, Kera