Week-6 Challenge: EV Drivetrain
1.There are 4 Types of Power Convertors used in Hybrid and Electric vehicle
- DC-AC Convertors- It is used for Converting the DC power to AC Power from battery to other devices for eg Motor,Coolant Pump etc We call it invertor also it converts DC voltage to High Voltage AC using Step Up Transformer
- DC-DC Convertors-It is being used for interfacing the fuel cell and the battery
- AC-DC Convertors- This is controlled by Rectifier
- Step Up Transformer and Step Down Transformer- Step Up transformer is used where the output voltage to be taken in higher form than input voltage
Step Down transformer is used where the output voltage to be taken in lower form than the input voltage
| 2 | Given:- | Motor and Controller Parameters: | ||||
| Rated Armature voltage= 72 V | V | 72 | ||||
| Rated armature current= 400 A | I | 400 | ||||
| Ra= 0.5Ω, KΦ= 0.7 Volt second | Ra | 0.5 | ||||
| Chopper Switching frequency= 400Hz | kΦ | 0.7 | ||||
| Tv = 24.7 + (0.0051)w2 | freq | 400 | ||||
| To Find:- | EV Steady State Speed at 70% | |||||
| Motor Volt=dutycycle*armature voltage | Duty cyle=0.7 | |||||
| V | 50.4 | |||||
| Calculation:- | According to formula given | |||||
| GIVEN Formula:- | TV'=24.7+ (.0051)w2 | w-Angular Speed | ||||
| DC Motor Formula | ||||||
| t=(V*kΦ/Ra)-(kΦ)^2/Ra)*w | ||||||
| t=50.4*(0.7/0.5)-((0.7)*(.7)/0.5) | ||||||
| t=70.56-0.98*w | ||||||
| Comparing with given formula,hence | ||||||
| 24.7+(0.0051)w2=70.56-0.98*w | ||||||
| w=38.9 | ||||||
| hence Motor rpm is 369 rpm | ||||||
3.
The Above Graph Shows Speed vs Torque https://drive.google.com/file/d/16UE6F73ugal7hrNDQ2hTkQWR9gkxWE_b/view?usp=sharing
4.The Author wants to explain about the Induction Vs Brushless DC motor,their Adavantage and disadvantages and Working principle
|
Induction Motor |
DC Motor |
Advantage |
Disadvantage |
|
The induction rotor has no magnets – just stacked steel laminations with buried peripheral conductors that form a “shorted structure.” |
The rotor includes two or more permanent magnets that generate a DC magnetic field magnetic field enters the stator core and interacts with currents flowing within the windings to produce a torque interaction between the rotor and stator. |
1.When induction motor is connected to 3 Phase power, torque produced at outset 2.Induction motor is Cheap 3.Magnetic Field can be controlled in Induction Motor |
1.Induction Motor Operates in AC only 2.It is difficult to control than DC Brushless motor |
- Both Uses 3 phase modulating invertors and Stators
Brushless motor requires position sensor also to operate