VALIDATION OF CONTROL LAW

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VALIDATION OF CONTROL
LAW - Integrated Simulation and Hardware in Loop
Simulation
S.KATHIRESAN
SCIENTIST F ENGINE CONTROL SYSTEM GROUP GAS
TURBINE RESEARCH ESTABLISHMENT BANGALORE
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VALIDATION
THE PROCESS WHICH PROVIDES SUPPORTING EVIDENCE
THAT THE SOFTWARE SATISFIES SYSTEM REQUIREMENTS
ALLOCATED TO SOFTWARE, AND SOLVES THE RIGHT
PROBLEM (e.g., CORRECTLY MODELS PHYSICAL LAWS) -
IEEE Std 1012-1998
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ENGINE CONTROL - OVERVIEW
HYDRO MECHANICAL SYSTEM
DECU (ENGINE)
ENGINE
Thrust
PLA (COCKPIT)
Feedback
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ENGINE CONTROL LAW CONFIGURATION
PLA
Mach No
MECU RHFCU INAS VGAS HYDRO-MECHANICAL
SYSTEMS
T1
ENGINE
THRUST
P1
P?
State
Feed back from engine
KADECU (Twin Lane Hot Stand by)
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VALIDATION STEPS

• Validation of the engine control system is being
  done by
• following methods
• Non-linear non-real time integrated engine
  simulation
• Hardware in the loop simulation (HILS)
• Engine testing
• Ground testing
• Altitude testing

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INTEGRATED SIMULATION

• Integrated simulation constituents
• Control laws and control schedules
• Non-linear models of hydomechanical systems
• Main fuel flow control unit
• Reheat fuel control unit
• VG actuation system
• Nozzle actuation system
• Non-linear thermodynamic engine model

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HYDROMECHANICAL SYSTEM MODEL

• All elements involved in the transients
• Second order model for each system valve
• Friction, Stiction flow force considered
• Algebraic loops to be solved
• - Loop breaker
• - Introducing small time constant

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SCHEMATIC OF REHEAT FUEL CONTROL UNIT
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MODELING OF AN ELEMENT
AFMT
QFMT
PFMTD
PBA
ZFMT
RFMT, HFMT
MATHEMATICAL MODEL FOR FLOWMETER
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MAIN ENGINE FUEL CONTROL UNIT
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MAIN FUEL SYSTEM MODEL VALIDATION
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VGAS SYSTEM MODEL VALIDATION
SLAM TEST
STEP RESPONSE
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ENGINE MODEL VALIDATION
Time (sec)
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STEP SIZE FOR VARIOUS MODELS
TYPICAL INTEGRATION STEP SIZES USED FOR NON REAL
TIME SIMULATION
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INTEGRATED SIMULATION TESTS
VALIDATION OF TRANSIENT/STABILITY REQUIREMENTS
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HARDWARE IN LOOP SIMULATION

• HILS - constituents
• Actual hardware of hydomechanical systems
• Main fuel flow control unit with burner
  simulator
• Reheat fuel control unit with burner simulator
• VG actuation system with loading system
• Nozzle actuation system with loading system
• Actual DECU hardware with Control and
  environmental software
• Real time thermodynamic engine model

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HILS SETUP
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HILS RIG FOR TESTING MECU AND RHFCU
DRIVE PAD
CONTROL PANEL

• SALIENT FEATURES
• 3 PADS 45 kW _at_ 12000 rpm, 280 kW _at_ 6000 RPM
  30000 rpm
• SYNCHRONISED SPEED
• AUTO/MANUAL CONTROL
• EFFICIENT BOOST CONTROL

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HILS RIG FOR TESTING VGAS AND NCS

• 4 SYNCHRONISED ACTUATORS
• MAX LOAD OF 160 kN
• LOAD THR SERVO ACTUATORS WITH LOAD CELL FEEDBACK

• 2 SYNCHRONISED ACTUATORS
• MAX LOAD OF 650 N
• LOAD THROUGH SPRINGS

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HILS VALIDATION
RESULTS OF HILS AND ENGINE RESULTS AT BANGALORE
TEST BED CONDITION
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HILS VALIDATION

• 11 Km, Mach No. 0.9 condition

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SUMMARY
INTEGRATED SIMULATION AND HILS TESTING ARE IDEAL
PROCESSES FOR VALIDATION
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THANK YOU
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INTEGRATED NOZZLE SYSTEM MODEL VALIDATION