Final Project: Electric Rickshaw modelling

Electric Rickshaw:

Electric rickshaws are a boon to the environment and a great way to get around town. They are emissions-free, quiet and efficient. They are also very affordable, which makes them a great option for those on a budget. Electric rickshaws are a great way to reduce traffic congestion and pollution levels in cities. There are many advantages of electric rickshaws over traditional petrol or diesel-powered rickshaws. Electric rickshaws are much cheaper to operate and maintain. They are also much quieter, which makes them ideal for use in residential areas. Electric rickshaws are also much more environmentally friendly, as they emit no pollutants. Electric rickshaws are a great option for those looking for an efficient, affordable and eco-friendly way to get around town.

Electric rickshaws have been around in India for many years now. They are a very popular mode of transportation, especially in congested urban areas. There are many advantages to using electric rickshaws over traditional petrol or diesel-powered vehicles. They are much cheaper to operate and maintain, and they emit no pollutants. Electric rickshaws are also much quieter than their petrol or diesel-powered counterparts, which makes them ideal for use in densely populated areas. The main disadvantage of electric rickshaws is that they have a limited range and need to be recharged frequently. This can be a problem in areas where there is no reliable electricity supply. Another issue is that the batteries used to power electric rickshaws are often very heavy, which can make the vehicles difficult to maneuver. Despite these disadvantages, electric rickshaws are a very popular transportation option in India and are likely to continue to grow in popularity in the years to come.

Electric rickshaws are typically three-wheeled vehicles with a small covered cabin for the driver and passengers. They are powered by an electric motor, which is usually located in the rear of the vehicle. Batteries are typically located under the seat or in the luggage compartment. Most electric rickshaws are designed to seat two or three people, although some larger models can seat up to six people. Many electric rickshaws also have a cargo area for carrying luggage or shopping bags. Electric rickshaws are typically much cheaper to operate than petrol or diesel-powered vehicles. They are also much quieter and do not produce any emissions, which makes them much more environmentally friendly. The main disadvantages of electric rickshaws are that they have a limited range and can take a long time to charge. In addition, they are not always allowed on main roads in some cities. Despite these disadvantages, electric rickshaws offer a number of advantages over traditional petrol or diesel vehicles, which is why their popularity is growing in many cities around the world.

The electric rickshaw typically has a metal frame, with the body of the vehicle being made of either metal or plastic. The wheels of the electric rickshaw are typically made of metal, although some models may have plastic or rubber tires. The electric rickshaw typically has a canopy to protect passengers from the sun and rain. The electric motor of the electric rickshaw is typically powered by batteries. The batteries are typically located in the rear of the vehicle, beneath the seats. The electric rickshaw may also have a solar panel located on the roof of the vehicle, which helps to recharge the batteries. The electric rickshaw typically has a controller, located on the handlebars, which the driver uses to control the speed of the vehicle. The electric rickshaw also has brakes, which are located on the rear wheels.

Electric Vehicle:-

a)Electric Vehicle is a vehicle that uses electric motors to produce power and a battery to store energy.

b) It uses an electric motor for propulsion and moving the vehicle instead of an internal combustion engine.

System level Block diagram of EV:-

The electric vehicle consists of-

a) Charging port- EV is charged through the charging port.

b) Onboard charger- It acts as AC to DC rectifier.

c) Battery- It stores the DC energy converted by an onboard charger.

d) Power Controller- It controls the power required by the motor through the battery as a mediator and provides the power to the motor when needed. An inverter changes the DC power stored in the battery to AC.

e) Motor - It produces the torque and supply power to rotate the wheel.

f) Drivetrain - It contains a differential gearbox and fixed gear as the motor is capable of generating large variations of torque needed by the vehicle to run.

g) Auxillary battery- To run the auxiliary components like headlight, wiper, etc.

h) Thermal management system- To maintain the engine and cabin temperature.

The losses to be considered while designing an electric powertrain are-

Motor loss, Accessory loss, Charging loss, Inverter Loss, Mechanical losses.

- More Key components of electric Vehicle:

• Transmission system: Mechanical power is delivered from the motor shaft to the wheels.
• Traction motor: Propulsion power unit which generates motion from electric power.
• Inverter and controller: Changing both the type and extent of electrical power from the battery to the motor.
• Traction battery pack: Energy storage unit which makes energy expenditure while driving the vehicle and acquire energy while charging.

- Design of an Electric Rickshaw:

Blocks used to design the model:

1) Tire:

Represents the longitudinal behavior of a highway tire characterized by the tire Magic Formula. The block is built from Tire-Road Interaction (Magic Formula) and Simscape Foundation Library Wheel and Axle blocks. Optionally, the effects of tire inertia, stiffness, and damping can be included.

A -

Connection A is the mechanical rotational conserving port for the wheel axle.

H-

Connection H is the mechanical translational conserving port for the wheel hub through which the thrust developed by the tire is applied to the vehicle.

N-

Connection N is a physical signal input port that applies the normal force acting on the tire.

The force is considered positive if it acts downwards.

S-

Connection S is a physical signal output port that reports the tire slip.

2) Vehicle Body:

Represents a two-axle vehicle body in longitudinal motion. The block accounts for body mass, aerodynamic drag, road incline, and weight distribution between axles due to acceleration and road profile. The vehicle can have the same or a different number of wheels on each axle. Optionally include pitch and suspension dynamics or additional variable mass and inertia. The vehicle does not move vertically relative to the ground.

H-

Connection H is the mechanical translational conserving port associated with the horizontal motion of the vehicle body.

V-

vehicle velocity

Nf-

Front Wheel normal force

Nr-

Rear wheel normal force.

3) Simple Gear:

Represents a fixed-ratio gear or gearbox. No inertia or compliance is modeled in this block. You can optionally include gear meshing, backlash, and viscous bearing losses.

Connections B (base) and F (follower) are mechanical rotational conserving ports.

4) Constant and PS constant:

This block creates a physical signal constant:

y = constant

The Constant parameter accepts both positive and negative values. The block output is a physical signal port.

5) Connection port:

6) Drive Cycle Source:

Generates a standard or user-specified longitudinal drive cycle. The block output is the vehicle longitudinal speed. You can import drive cycles from:

- Predefined sources

- Workspace variables, including arrays and time series objects

- mat, xls, xlsx, or txt files

Use the fault tracking parameters to identify drive cycle faults within specified speed and time tolerances.

7) Multiport Switch:

Pass through the input signals corresponding to the truncated value of the first input. The inputs are numbered top to bottom (or left to right). The first input port is the control port. The other input ports are data ports.

8) Longitudinal driver:

A parametric longitudinal speed tracking controller for generating normalized acceleration and braking commands based on reference and feedback velocities.

Use the external actions to input signals that can disable, hold, or override the closed-loop commands determined by the block. The block uses this priority for the input commands: disable, hold, override.

9) Controlled Voltage source:

The block represents an ideal voltage source that is powerful enough to maintain the specified voltage at its output regardless of the current passing through it. The output voltage is V = Vs, where Vs is the numerical value presented at the physical signal port.

10) Controlled PWM Voltage:

This block creates a Pulse-Width Modulated (PWM) voltage across the PWM and REF ports. The output voltage is zero when the pulse is low and is equal to the Output voltage amplitude parameter when high. The duty cycle is set by the input value. At time zero, the pulse is initialized as high unless the duty cycle is set to zero or the Pulse delay time is greater than zero.The Simulation mode can be set to PWM or Averaged. In PWM mode, the output is a PWM signal. In Averaged mode, the output is constant with a value equal to the averaged PWM signal.

11) H-Bridge:

This block represents an H-bridge motor drive. The block can be driven by the Controlled PWM Voltage block in PWM or Averaged mode. In PWM mode, the motor is powered if the PWM port voltage is above the Enable threshold voltage. In Averaged mode, the PWM port voltage divided by the PWM signal amplitude parameter defines the ratio of the on-time to the PWM period. Using this ratio and assumptions about the load, the block applies an average voltage to the load that achieves the correct average load current. The Simulation mode parameter value must be the same for the Controlled PWM Voltage and H-Bridge blocks.

12) Current Sensor:

The block represents an ideal current sensor, that is, a device that converts current measured in any electrical branch into a physical signal proportional to the current. Connections + and - are conserving electrical ports through which the sensor is inserted into the circuit. Connection I is a physical signal port that outputs the current value.

13) Controlled Current Source:

The block represents an ideal current source that is powerful enough to maintain the specified current through it regardless of the voltage across it. The output current is I = Is, where Is is the numerical value presented at the physical signal port.

14) Solver Configuration:

Defines solver settings to use for simulation.

15) Electrical Reference:

Electrical reference port. A model must contain at least one electrical reference port (electrical ground).

16)Li-ion Battery:

Implements a generic battery model for most popular battery types. Temperature and aging (due to cycling) effects can be specified for Lithium-Ion battery type.

17) DC Motor:

This block represents the electrical and torque characteristics of a DC motor. The block assumes that no electromagnetic energy is lost, and hence the back-emf and torque constants have the same numerical value when in SI units. Motor parameters can either be specified directly or derived from the no-load speed and stall torque. If no information is available on armature inductance, this parameter can be set to some small non-zero value. When a positive current flows from the electrical + to - ports, a positive torque acts from the mechanical C to R ports. Motor torque direction can be changed by altering the sign of the back-emf or torque constants. Here we are using a permanent magnet DC motor.

18) Mechanical Rotational reference:

This block represents a mechanical rotational reference point, that is, a frame or a ground. Use it to connect mechanical rotational ports that are rigidly affixed to the frame (ground).

19) Scope:

The scope is used to get the output of the system.

20) Integrator:

Continuous-time integration of the input signal.

21) Divide:

Multiply or divide inputs.

22) Display:

Display input or output values.

22) Controller Temperature:

This block measures temperature in a thermal network. There is no heat flow through the sensor. The physical signal port T reports the temperature difference across the sensor. The measurement is positive when the temperature at port A is greater than the temperature at port B.

Model Construction and Explanation:

Vehicle subsystem:

The vehicle subsystem blocks contain the tire arrangement 4 tires arranged as from wheels and rear wheels.The axle blocks are connected to the tire block next to each other to form as front axle and rear axle. Hub is also connected to hub.

A vehicle body block is present and the connections are made to the necessary connection ports of the tire.

For simplification, I had taken the simple gear.

The remaining ports are connected to constants or connection ports.

Electric Vehicle Model:

This the electric vehicle model designed and the model is also attached in slx format.

The parameters set are:

Vehicle body parameters

Tire parameters:

Controlled PWM Voltage:

DC motor parameters:

Drive cycle WOT:

Drive Cycle FTP 75:

Battery parameters:

Results:

The input data are:

Wide Open Throttle

By running the Vehicle with WOT Drive cycle for 200 sec. the distance travelled is 4.133km.

• The actual Speed is approximately followed the 85% of reference Drive cycle.
• Energy consumed by the battery is increased linearly till 100 sec. to approx. 1050 Wh and then reduced gradually due to back EMF and finally at the end of the cycle, energy consumption is reached to 900 Wh.
• The SoC% of the battery is reduced to ≈91%≈91% at 100th sec and after that 100 to 200 sec., the battery get charged by by back EMF. Finally at the end of the 400 sec. the SoC is of ≈94.2%.
• The Temperature of Motor is increased to 1800C
• The Temperature of Controller is 1100C

. For FTP75 Drive Cycle:

By running the Vehicle with FTP75 Drive cycle for 2474 sec. the distance travelled is 19.44km.

• The actual Speed is approximately followed the 90% of reference Drive cycle.
• Energy consumed by the battery is ≈≈3⋅104Wh3 at the end of the cycle.
• The SoC% of the battery is reduced to ≈83%
• The Temperature of Motor is increased to 3700C
• The Temperature of Controller is ≈1800C

3. For US06 Drive cycle:

To increase the speed of the vehicle, the output voltage amplitude is applied to 400 V

By running the Vehicle with a Manually prepared Drive cycle for 120 sec. the distance traveled is 3.876km.

• The actual path of the speed is approximately followed the of reference Drive cycle as above.
• Energy consumed by the battery is varied with respect to time and distance ≈≈10500Wh at the end of the cycle
• The SoC% of the battery is reduced to ≈94.2%
• The Temperature of Motor is increased to ≈2600C.
• The Temperature of Controller is ≈1450C

Conclusion:

• Here I have compromised with the temperature of Motor and controller to achieve vehicle speed is near to reference speeds. Since I haven’t used any cooling system in the model. In the real time application, the motor temperature is less than 100⁰C.
• In the real time application, the motor, battery & controller temperature is controlled by air cooling. Hence, the temperature of this components is not increased to this extent.
• Hence, Created a MATLAB model of an Electric Rickshaw (three wheel passenger vehicle) by using Li-ion battery, PM Brushed DC Motor.
• Detremined the variations of Temperature of Motor and controller, SoC% and Energy consumed by the by vehicle for all the three Reference Drive cycles (i.e.; FTP75, WOT, Manually prepared).
• This Battery powered Rickshaw will be the most popular mode of transport in the future.