lecture 29 modeling diesel engine gov sys
TRANSCRIPT
Diesel Engine Governor Model
Dr M S R Murty
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Diesel engine model
• The efficiency of the combustion is the ratio of the effective horsepower developed by the engine and available on its crankshaft to the heat consumed during the same time
• Heat Consumption = (Fuel consumption rate, Kg/sec)*(Heating value, Kcal/Kg)
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Diesel engine model
• Model describes the fuel consumption rate as a function of speed and mechanical power output of the engine.
• The diesel engine is usually modelled by a simple first order model relating the fuel consumption to the engine mechanical power.
• Transfer function of a reciprocating engine involves a small but significant time delay associated with the mean time between firing.
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• The efficiency of the combustion is the ratio of the effective horsepower developed by the engine and available on its crankshaft to the heat consumed during the same time
• Combustion efficiency is assumed constant in power system studies
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Diesel Engine and Control modelTorque developed
DieselConsumption rate
Effective pressure
Pressure lossSpeed
PI Controller and Actuator
Є= Combustion efficiency (assumed constant )
Reference speed
InertiaEngine Model
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Diesel Engine Generator Model
• Model consists of the models of• Synchronous generator model• Diesel engine together with the governor and• Automatic voltage regulator (AVR).
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Simulink Model
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PSS/E Model
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Transfer function Block diagram
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DEGOV1
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TGOV1 in PSS/E
RT1 (>0) (sec) VMAX VMIN T2 (sec)
T3 (>0) (sec) Dt
'TGOV1' 1 0.05 0.5 0.85 0.3 1 1 0
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