Project-1: Powertrain for aircraft in runways

1 The maximum weight of the aircraft is shown in the table (ref:wikipedia)

Type	MTOW [kg]
Antonov An-225	640,000
Scaled Composites Model 351 Stratolaunch	589,670
Airbus A380-800[1][2][3]	575,000
Boeing 747-8F	447,700
Boeing 747-8	443,613
Boeing 747-400ER	412,770
Antonov An-124-100M	405,060
Boeing 747-400	396,900
Lockheed C-5 Galaxy[4][5][6]	381,000
Boeing 747-200[7]	377,840
Boeing 747-300[7]	377,840
Airbus A340-500[8]	371,950
Airbus A340-600[8]	367,400
Boeing 777F	347,800
Boeing 777-300ER	351,800
Boeing 777-200LR	347,450
Boeing 747-100[7]	340,200
Airbus A350-1000	308,000
Boeing 777-300	299,370
Boeing 777-200ER	297,550
Airbus A340-300[8][9]	276,700
McDonnell Douglas MD-11	273,300
Airbus A350-900	270,000
Ilyushin Il-96M	270,000
McDonnell Douglas DC-10	256,280
Boeing 787-9[10]	254,000
Boeing 787-10[10]	254,000
Airbus A340-200[8][11]	253,500
Airbus A330-900	251,000
Ilyushin IL-96-300	250,000
Airbus A330-300[12][13]	242,000
Airbus A330-200[12][13]	242,000
Lockheed L-1011-500	231,300
Boeing 787-8[10]	228,000
Lockheed L-1011-200	211,400
Ilyushin IL-86	208,000
Boeing 767-400ER	204,000
Airbus A300-600R[14]	192,000
Boeing 767-300ER	187,000
Concorde	185,000
Airbus A300-600[14]	163,000
Boeing 767-300	159,000
Airbus A310-300[14]	157,000
Vickers VC10	152,000
Boeing 707-320B[15]	151,000
Boeing 707-320C[15]	151,000
Douglas DC-8-61	147,000
Airbus A310-200[14]	142,000
Airbus A400M	141,000
Douglas DC-8-32	140,000
Douglas DC-8-51	125,000
Boeing 757-300	124,000
Boeing 707-120B[15]	117,000
Boeing 757-200	116,000
Boeing 720B[16]	106,000
Boeing 720[16]	104,000
Tupolev Tu-154M	104,000
Tupolev Tu-204SM	104,000
Convair 880	87,500
Boeing 737-900	85,000
Boeing 737-900ER	85,000
Boeing 727-200 Advanced[17]	84,000
Airbus A321-100[18]	83,000
Boeing 737-800	79,000
Boeing 727-200[17]	78,000
McDonnell-Douglas MD-83	73,000
Boeing 727-100[17]	72,500
Boeing 727-100C[17]	72,500
McDonnell-Douglas MD-90-30	71,000
de Havilland Comet 4	70,700
Boeing 737-700	70,000
Airbus A320-100[18]	68,000
Boeing 737-400	68,000
de Havilland Comet 3	68,000
Boeing 377	67,000
Boeing 737-600	66,000
Airbus A220-300	65,000
Hawker Siddeley Trident 2E	65,000
Airbus A319[18]	64,000
Boeing 737-300	63,000
Boeing 737-500	60,000
Airbus A220-100	59,000
Airbus A318[18]	59,000
Boeing 717-200HGW	55,000
Douglas DC-7	55,000
de Havilland Comet 2	54,000
Boeing 717-200BGW	50,000
de Havilland Comet 1	50,000
Douglas DC-6A	48,600
Douglas DC-6B	48,500
Embraer 190[19]	48,000
Caravelle III	46,000
Fokker 100	46,000
Douglas DC-6	44,000
Avro RJ-85	42,000
Handley Page Hermes	39,000
Embraer 175[20]	37,500
Bombardier CRJ900[21]	36,500
Embraer 170[22]	36,000
Bombardier CRJ700	33,000
Douglas DC-4	33,000
Vickers Viscount 800	30,400
Bombardier Q400	28,000
Bombardier CRJ200	23,000
ATR 72-600	22,800
Saab 2000	22,800
Embraer ERJ 145	22,000
ATR 42-500	18,600
Saab 340	13,150
Embraer 120 Brasilia	11,500
BAe Jetstream 41	10,890
Learjet 75[23]	9,752
Pilatus PC-24[24]	8,300
Embraer Phenom 300[25]	8,150
Beechcraft 1900D	7,765
Cessna Citation CJ4[26]	7,761
de Havilland Hercules	7,000
Embraer Phenom 100	4,800

2. Relative speed between the object and air which causes the aircraft to lift is called airspeed. Ground speed is a vector quantity so a comparison of the ground speed to the wind speed must be done according to rules for vector comparison.(Ref: https://www.grc.nasa.gov/www/k-12/airplane/move.html#:~:text=Airspeed%20is%20the%20vector%20difference,speed%20and%20the%20wind%20speed.&text=On%20a%20perfectly%20still%20day,less%20than%20the%20ground%20speed.)

3. Most aircraft cannot move in reverse manner since they dont have a reverse gear. Also more fuel is spent in taxing rather than towing.It also causes louder and noiser operation.

4.

( ref: https://www.fp7-restarts.eu/index.php/home/root/state-of-the-art/objectives/2012-02-15-11-58-37/71-book-video/parti-principles-of-flight/126-4-phases-of-a-flight.html)

There are different movements of aircraft.

1. Taxing: Taxiing refers to the movement of an aircraft on the ground, under its own power. The aircraft moves on wheels. The aircraft moves within the yellow line to avoid any collison with near by objects or buildings.
2. Towing happens when the aircraft is towed by a land vehicle.
3. The thrust to propel the aircraft forward comes from its propellers or jet engines. Steering is achieved by turning a nose wheel or tail wheel/rudder; the pilot controlling the direction travelled with their feet.
4. Takeoff is the phase of flight in which an aircraft goes through a transition from moving along the ground (taxiing) to flying in the air, usually starting on a runway. Usually the engines are run at full power during takeoff.
5. Climb: Following take-off, the aircraft has to climb to a certain altitude (typically 30,000 ft or 10 km) before it can cruise at this altitude in a safe and economic way. A climb is carried out by increasing the lift of wings supporting the aircraft until their lifting force exceeds the weight of the aircraft. Once this occurs, the aircraft will climb to a higher altitude until the lifting force and weight are again in balance. The increase in lift may be accomplished by increasing the angle of attack of the wings, by increasing the thrust of the engines to increase speed (thereby increasing lift), by increasing the surface area or shape of the wing to produce greater lift, or by some combination of these techniques.
6. Cruise is the level portion of aircraft travel where flight is most fuel efficient. It occurs between ascent and descent phases and is usually the majority of a journey.
7. A descent during air travel is any portion where an aircraft decreases altitude either for landing, bad traffic or climate etc.
8. Landing is the last part of a flight, where the aircraft returns to the ground.

5. The amount of power that an engine is allowed to produce for a limited period of time for takeoff. The use of takeoff power is usually limited to 5 min for reciprocating engines and up to 2½ min for gas turbine engines.

An aircraft tire is designed to withstand extremely heavy loads for short durations.The number of tires required for aircraft increases with the weight of the aircraft, as the weight of the airplane needs to be distributed more evenly. Aircraft tire tread patterns are designed to facilitate stability in high crosswind conditions, to channel water away to prevent hydroplanning and for braking effect.R olling resistance occur by friction between tire and ground.When the aircraft is moving in ground by taxing or towing at that time rolling resistance force is act against the traction force of aircraft.

The tire pressure of aircraft is very high to minimize the rolling resistance and withstand the weight. Usually tire pressure is 190 to 320 psi based on aircraft types it’s varies.

A large braking force is required for the aircraft to stop. There is deedicated brake unit on each wheel to stop the aircraft.

Part B:

6,. Excel file for calculation is attached.

7. The simulink model for total traxtive effort calculation is shown below.

7. The components of EV powertrain includes

• Battery pack - which consist of lithium ion or Lead acid battery and stores the energy required to run the vehicle.
• DC- AC Converter- DC supplied by battery pack is converted to AC and supplied to the motor.
• Electric Motor- converts electrical energy to mechanical energy required for the movement of vehicle.
• ON baord charger- controls the amount of current flowing through the battery.

Assumptions are require which is below table shows.

motor assumed parameter
Radius of tyre tug	0.653m
gear ratio	8
transmission efficiency	87%
motor efficiency	95%
battery capacity	380v
power required to aircraft	261.8kw
force required to aircraft	31.4kN
speed of vehicle	8.33m/s
towing operation	30min

Velocity of vehicle = 8.33m/s

Force is required to push/pull aircraft = 31.4KN

Power required = 261.8 KW

Let us assume,

Radius of tyre for tug = 0.635m

Gear ratio = 8

Transmission efficiency(nt) = 87%

Motor efficiency(nm) = 95%

Torque required for wheel(Tw) = total force*radius in meters

= 31.4*0.63

= 19.782KNm

Motor torque = wheel torque/(gear ratio*nt)

= 19.782/(8*0.87)

= 2.841 KNm

For nm =95%

Required motor torque = 2.841/0.95

= 2.99KNm

Similarly for power,

Power required by motor considering all efficiencies = 261.8/(0.87*0.95)

= 316.75kw

Assume time duration of towing operation is

Total energy consumed = 316.75*0.5

= 158.37 kWh

If we consider battery capacity = 380kw is used by towing vehicle then,

Duty cycle = required power / rated power

= 316.75/380

= 0.833

Therefore the controller will be able to provide a duty cycle ranging from 0 to 83% in order to control towing speed.

Simulation of four quadrant DC chopper drive 200HP drive is shown below

200 HP DC motor is separately excited with a constant 150 V DC field voltage source. The armature voltage is provided by an IGBT converter controlled by two PI regulators. The converter is fed by a 515 V DC bus obtained by rectification of a 380 V AC 50 Hz voltage source. In order to limit the DC bus voltage during dynamic braking mode, a braking chopper has been added between the diode rectifier and the DC7 block.

The first regulator is a speed regulator, followed by a current regulator. The speed regulator outputs the armature current reference (in p.u.) used by the current controller in order to obtain the electromagnetic torque needed to reach the desired speed. The speed reference change rate follows acceleration and deceleration ramps in order to avoid sudden reference changes that could cause armature over-current and destabilize the system. The current regulator controls the armature current by computing the appropriate duty ratios of the 5 kHz pulses of the four IGBT devices (Pulse Width Modulation). For proper system behaviour, the instantaneous pulse values of IGBT devices 1 and 4 are opposite to those of IGBT devices 2 and 3. This generates the average armature voltage needed to obtain the desired armature current. In order to limit the amplitude of the current oscillations, a smoothing inductance is placed in series with the armature circuit.