Final Project: Design of an Electric Vehicle

BLOCKDIAGRAM

BLOCKSET USED IN THE MODEL

Tire(Magic Formula)

We will connect the shaft of the motor through the transmission system to the rear axel. A is the axel, the left are the rear wheels and right are front axel, which are connected to each other ,similarly the H(HUB) are connected to rear and front wheel.N on both the front wheel and rear wheel are connected to NR(normal rear) and NF(normal front) of the vehicle body.S is the slip which can be given as an input by the user.

SYSTEM PARAMETERS

Gemoetry

Rolling radius: 0.32 m

Dynamics

Compliance: No compliance - Suitable for HIL simulation/ Specify stiffness and damping

we can choose specific stiffness and damping and provide and provide suitable Longitudinal stiffness andLongitudinal damping , i N/m and N/(m/s) respectively.

Tire inertia: 0.5 kg*m^2

Inertia: Have two option

No interia /Specify inertia and initial velocity

Specify inertia and initial velocity- Tire inertia in kg*m^2 and

Initial velocity in rad/s

Rolling Resistance

we can turn of the rolling resistance to simplify the model calculatio and time.if rolling resistance is ON.we have to provide the subsequent values.

Resistance Model : Constant coefficient/Pressure and velocity dependent

Constant coefficient: 0.015

Velocity threshold:0.1 m/s

Vehical Body

Vehicle body : This block accounts for the body mass aerodynamics drag ,road inclination, and weight distribuation between axel dur to acceleration and road profile.

H(hub) part is connected to rear and front wheel ,normal forces are alos connected with tire.W is the eind velocity and beta angle (gradient) agle of the road the vehicle is movig on.

MODEL PARAMETERS

Drag:

Frontal area: 3 m^2

Drag coefficient: 0.4

Air density: 1.18 kg/m^3

velocity : priority -high m/s

for simplicity pitch dynamics has been turned off.

SIMPLE GEAR WITH INETRIA BLOCK

Meshing losses:

friction model: constant efficiency

Efficiency: .0.86

follower power threshold: 0.001

Motor

The DC Motor block represents the electrical and torque characteristics of a DC motor using the following equivalent circuit model:

You specify the equivalent circuit parameters for this model when you set the Model parameterization parameter to By equivalent circuit parameters. The resistor R corresponds to the resistance you specify in the Armature resistance parameter. The inductor L corresponds to the inductance you specify in the Armature inductance parameter

POWER CONVERTER

H_BRIDGE

In our model we are using H-bridge ,motor should be running in a reverse direction we also we also want regenrative braking to happen, we want our motor to ru in all four direction.

In oder to have 4-quadrant operation of the motor ,we use simple power converter H-bridge ,it is nothing but connection of four switches.

If we use BLDC motor we will be having a three phase inverter ,if we take simple motor likw a DC motor ad want forward and reversse motoring & regenrative effect we can use 4 switch base power converter,

BATTERY

DRIVER CONTROLLER

The Longitudinal Driver block implements a longitudinal speed-tracking controller. Based on reference and feedback velocities, the block generates normalized acceleration and braking commands that can vary from 0 through 1. You can use the block to model the dynamic response of a driver or to generate the commands necessary to track a longitudinal drive cycle

VelRef: Vehicle referance speed acts as in input from the drive cycle, it can take multiple inputs from the user like signal bulider and also form workspace .

VelFdbk:Vehicle feedback speed ,it is the velocity received from the vehicle body block.

Grade: Gradient

AccelCmd: acceleration output to ref of PWM controller via controlled voltage source.

DecelCmd:deceleration output to brake input of power converter controller via controlled voltage source

Controller

DRIVE CYCLE

• The Drive Cycle Source block generates a standard or user-specified longitudinal drive cycle. The block output is the specified vehicle longitudinal speed, which you can use to:

  • Predict the engine torque and fuel consumption that a vehicle requires to achieve desired speed and acceleration for a given gear shift reference.

  • Produce realistic velocity and shift references for closed loop acceleration and braking commands for vehicle control and plant models.

  • Study, tune, and optimize vehicle control, system performance, and system robustness over multiple drive cycles.

Identify the faults within tolerances specified by standardized tests, including: