PERFORMANCE OF PITCH AND STALL REGULATED TIDAL STREAM TURBINES

ERFAN.K

ROLL NO:14

S8,EEE:

INTRODUCTION

• Tidal power is a form of hydropower.• It is a renewable energy source which convert energy

of tides to electricity.• It has a high potential for future power generation.• In middle ages and roman times tidal power is used in

mill grains.• First tidal power plant is RANCE TIDAL POWER

STATION ,FRANCE ,1966.

TIDAL STEAM TURBINE

• TST extract kinetic energy from tides.• TSTs are mainly bottom mounted, low solidity,

horizontal axial flow rotors.• Turbulence and waves vary the flow speed.• For regulated power output pitch and stall regulated

TSTs are used.• In pitch regulated TSTs the pitch angle of blade is varied.• Actively or passively induced stall is used in stall

regulation

TIDAL POWER

• Power extracted from tidal flow

• Tip speed ratio

• Compare with wind turbines TSTs are low speed.• Ratio of radii of TSTs and WT is

0.54.• Tip speed ratio is 0.3.

TST CONFIGURATION

HYDRODYNAMIC MODEL

• Hydrodynamic torque

PITCH CONTROL

POWER CURVE TORQUE CURVE

STALL CONTROLL

POWER CURVE TORQUE CURVE

Pitch angle control for above rated speed

PITCH REGULATED TST ANALYSIS

• Above rated speed the system is active• Pitch system consist of accutator,rate limiter,angle

limiter.• Linerised system equation

• Plant dynamic equation is

BODE PLOT OF PITCH CONTROL SYSTEM

INCLUDING RESONANT POLES

AND ZEROS

LOW FREQUENCIES

CONTROL DESIGN

•Control design equation

•Bandwidth is reduced to 300-490 rad/s

•Obtained good stability margin

Stall regulated control strategy

STALL REGULATED TST

• Reference speed

•Generator speed

•Plant equation

BODE PLOT

INCLUDING RESONANT POLES AND ZEROS

LOW FREQUENCIES

CONTROL DESIGN

•Before deep stall

•After deep stall