Project-1: Powertrain for aircraft in runways
Answer 6 A:-
Considering total mass the aircraft (including payload) for airbus A380=575000 kg.
Mass of the pushback=1000 kg (assumed)
Rolling resistance Frr:-
we know that Frr= μrr* m*g
for aircraft:-
Frr= 0.002*575000*9.81
=11281.5 N
=11.2815 KN
for the Towing Vehicle:-
Frrt=0.002*1000*9.81=19.62N
As the towing vehicle resistance is so less compared to the Aircraft beacause this is heavy aircraft so this can be neglected.
Aerodynamic resistance (Far)-
Far= 0.5*ρ*Cd.A.v^2
= 0.5*1.125*0.025*150*16=33.75 N
As the vehicle and plan is moving at very low speed Aerodynamic resistance can be neglected.
Hill cimbing resistance- Runways are constructed flat so Gradient reisistance/ hill climbing force is neglected.
Total Tractive Force:- Ft=Frr+Far
Ft=11.2815KN
Power Required:-
P=Ft * V= 11.2815*4=45.26KW
The minimum power required by towing vehicle is KW.
6B- Simulink Model-
ANSWER7-
Estimation of Duty Cycle:
Based on the calculation done in study 6.
The power required for towing of the aircraft is 45.26 kW. Motor considered for the drive train is REB 90.
| Type | Voltage | Continuous/Peak power | Working Rotation | Max Torque | Weight | Cooling |
| REB 90 | 400-800 V | 60-70 KW/80 KW | 1500-4000 RPM | 300Nm | 22000g | Air/Hybrid (air+fluid) |
Considering 60 KW as continuous power,so the voltage will be 400 V battery power is considered to be 550v.
Duty cycle is given by Vo/Vb
Where Vo is motor required voltage Vb is battery voltage.
D= 400/550=0.7272
As there will be losses due to the resistance of FET and inductance. Correction factor is considered to be 90%.
As there is 10% loss, the voltage demanded by the motor should be 10% more than required
So the voltage demand should be around 440 V from the battery.
Assumed Parameters
|
Mass of aircraft |
575000 kg |
|
Mass of the push back truck |
1000 kg |
|
Coefficient of rolling resistance |
0.002 |
|
Drag Coefficient |
0.025 |
|
Air density |
1.125 kg/m^3 |
|
Frontal Area |
150 m^2 |
|
Velocity |
4 m/s |
|
Uphill gradient |
0 deg |
|
Battery Voltage |
550 V |
|
Correction Factor |
0.8 |
Block diagram:-
Simulink Model:-
Output:-
From the motor:-
From the battery:-
Excel Data:-
