Week-6 Challenge: EV Drivetrain

Note : i am use the word file to write down the equestion but it cannot display here i am attage the file please go through that.

1. Which types of power converter circuits are employed in electric and hybrid electric vehicle?

There are four types of power convertor we use for electric and hybrid electric vehicles.

• DC to DC convertor
• DC to AC convertor
• AC to DC convertor
• AC to AC convertor

This four types we will use based on your need of convertor

• DC to DC Convertor: in DC to DC convertor we gives DC Supply as input And get DC supply as an output the voltage and current value become changes are in same proposnal.it means input power and output power are remains same only change the voltage and current based on requirement. based on this operation there are three types of DC to DC convertor

1. Buck convertor
2. Boost convertor

• Buck convertor: in buck convertor we decreases the voltage and increases the current in same proposnal that means input power is same as output power.
• Boost Convertor: in boost convertor. We decreases the Current and increases the voltage in same proposnal that means input power is exactly equal to output power.

Basically this type of the convertor use for satisfy the required specification based on present supply and safety propose because the if we supply more power than required power then system get damage.

eg: the motor of electric vehicle is required 300v to 500v then battery does not gives that much voltage to motor then we use the boost convertor to increases the voltage and decreases the supply current.

• DC to AC convertor: this type of convertor mostly use for the home appliances. When solar panel generate the energy and that energy will store back in battery. The battery store supply in DC form that energy we will use for different appliances then we convert it in to AC form by using electronic switches such as BJT, mosfet, IGBT etc.

In electric and hybrid electric vehicle we use energy from battery and source is in DC form then we convert it in to AC for different appliances such as display, lightening, music player, and dashboard of vehicle.

• AC to AC Convertor : in this convertor input is voltage and frequency and output is in voltage and frequency with different values there are four types of

2. AC to AC convertor with DC link.
3. Matrix Convertor.
4. Hybrid matrix convertor.
5. Cycloconvertors: In this type the frequency of the system is changes means we increases the frequency and decreases the AC power of the signal. In this type we does not have DC link. And avoid the conversion of the AC to DC. Means more losses are happen.
6. AC to AC convertor with DC link: as name suggest that we convert the AC in DC and then convert in to AC. When we convert the AC in to DC by using Rectifier and we convert DC to AC by using invertor.
7. Matrix Convertor: in matrix convertor we convert the AC to DC then we convert the DC into AC. But in AC to DC convertor with DC link contain more losses happen to convertor but in this convertor we reduces the losses. And increases the efficiency of the convertor. In matrix convertor we use IGBT switch to convert it.
8. Hybrid matrix convertor: this type is similar to matrix convertor in that they combine the AC to DC then DC to AC design by using matrix form.it is unidirectional switches and two convertor switch.

4.AC to DC Convertor: In AC to DC convertor we gives input as a AC signal and get a DC Signal. We are mostly use this type in day to day life. AC supply is given from the generation with 230v and 50 Hz supply then we convert it in to DC for different appliances. We convert 230v to 15v using step-down transformer but 15v is in ac form then we apply Rectifier. To convert AC in to pulse setting DC. But we does not get exact DC then we apply Filter to get exact DC supply.

In hybrid electric vehicle or electric vehicle we require charger to charge the vehicle. Generator station Supply is given from AC form and battery required supply in DC form then we require to convert AC in to DC.

2.

Mass of vehicle: 1000kg

Cd=0.2; A=2 m^2; Co=0.009, C1=1.

Rho=1.1614; radious of wheel :11 inch.=0.2794m

1000*9.8*0.009= 88.29N

The traction force is the reqired force to vehicle then is calculate based on rolling resistance and Aerodynamic force.

Ftr =T*G/r = Frr + Far

T/0.2794 = 88.29 +0.23228V^2

Then we convert the linear velocity to rotational velocity then we convert by V=r*

T/0.2794 = 88.29 +0.23228^2)

T=0.005066^2 + 24.66 ……………………(1)

That much torque is required for the vehicle to operate the vehicle then we calculate the motor torque of the motor.

Vo=V*dt

Vo=72*0.7 = 50.4v

We know the relation between the torque and speed of the motor

…………(2)

From above two equations we get

0.005066^2 + 24.66 =

From above equation we get the speed of the vehicle

We consider only positive speed for forward vehicle speed of vehicle is 35.05 rad /sec.

3.

The main difference between the vehicles is only changes in rotor of the motor. In BLDC motor we use permanent magnet and induction motor is nonmagnetic rotor.

When the current flowing in the stator winding it generate the rotor magnetic field then current carrying conductor placed in the conductor then it produces the torque then rotor frequency is the the difference between the stator frequency and supply frequency.

In induction motor the torque is generated is totally depends on the three phase power supply. Induction motor does not required the invertor. In BLDC motor does not produces starting torque then we require the invertor to generate the torque but induction motor generate the starting torque.

Induction motor is directly applied to induction motor. It does not required invertor. Induction motor is operate on the AC supply. But battery gives DC supply. For that in order to rectify the supply in order to invertor drive from induction drive from a dc power supply or battery.

DC brushless motor has less heat losses such as iron losses and core losses. Compare to other type DC motor. For induction motor it required 85% of power factor.

The DC motor required trapezoidal back EMF. And Induction motor required sinusoidal back emf then accuracy of the induction motor is more compare to BLDC motor. But still not decided which motor is best for electric vehicle. The most of the common component are in between the vehicles.

In this question we discuss the difference between the two types of motor that is DC brushless motor and induction motor. The writer cannot decide the which motor is best for electric vehicle. Both motor require the phase supply to operate the vehicle. In this link they discuss the construction, working and comparison between the two motor types. The DC motor contain two or more magnetic field on the rotor that generate the magnetic field that magnetic field enter the magnetic field enter the starter core and interact with the current carrying conductor then it produces the torque interaction between the stator and rotor current. For rotor it require the power and polarity. The stator current is continuously varying but vehicle require the constant torque of the motor. Then BLDC motor is totally depend on the invertor to operate the vehicle on constant speed.