Final Project: Electric Rickshaw modelling
Aim:
To Create a detailed MATLAB model of an Electric Rikshaw (3-wheel passenger vehicle).
Obejectives:
1. Rear wheels driven by brushed type motor.
2. Assume efficiency points of motor controller and motor.
3. Make an excel sheet of all input and assumed data.
4. Results: For any 3 standard driving cycles show energy consumption , temperature rise of motor
and controller.
Theory:
E-rickshaws are small vehicles, with three wheels and use electric power from batteries to run. They
use an electric motor as engine which draws electric power from the rechargeable batteries installed
in the rickshaw body. These battery operated vehicles are perfect for small distant transport, both
cargo and people; they are perfect for running on narrow streets because of their small size. But the
biggest reason for their popularity is low operating cost and zero pollution. They are like normal
rickshaws but powered by electric motor instead of petrol or diesel motor. They are best for pollution
free, environmental friendly transport system in short distances. Actually they are not capable of
running long distance.
E-rickshaws are now one of the preferred modes of transport in streets because of its low maintenance
cost, low fuel cost, eco-friendly, no noise pollution, easy to drive and last but not the least livelihood,
e-rickshaw is a boon to the common Man. Without putting in much physical efforts and without
investing much amount of money, the earning is quite good for an e-rickshaw driver and hence it is an
important means of livelihood for many.
These e-rickshaws consist of 3 wheels with a differential mechanism at rear wheels. Basically these
vehicles have a mild steel tubular chassis. The motor is brushless DC motor manufactured mostly in
India and China. The electrical system used in Indian version is 48V DC can run 90-100 km/full
charge. Basic seating capacity is driver plus 4 passengers.
These vehicles are now started using in transporting light weight goods as e-loader. Hence there are
lots of opportunities of income.
There are two types of e-rickshaw:
1. E-Rickshaw (Passenger)
2. E-Rickshaw (Cargo)
1. E-Rickshaw (Passenger)
“E-rickshaw” means a special purpose battery operated vehicle having three wheels and intended to
provide last mile connectivity for transport of passengers for hire or reward, provided
i) Such vehicle is constructed or adapted to carry not more than four passengers, excluding the driver,
and not more than forty kilograms luggage in total.
ii) The net power of its motor is not more than 2000 W.
iii) The maximum speed of the vehicle is not more than 25km/h.
Electric rickshaws (also known as Tuk Tuk, e-rickshaw) have been becoming more popular in some cities
since 2008 as an alternative to auto rickshaws and pulled rickshaw because of their low fuel cost, and less
human effort compared to pulled rickshaws. They are being widely accepted as an alternative to Petrol/Diesel
/CNG auto rickshaws. They are 3 wheels pulled by an electric motor ranging from 650-1400 Watts. They are
mostly manufactured in China, only a few other countries manufacture these vehicles.
Battery-run rickshaws could be a low-emitter complementary transport for the low-income people,
who suffer most from a lack of transport facility, if introduced in a systematic manner according to
experts.
The electric automobile did not easily develop into a viable means of transportation. Research waned
from 1920-1960 until environmental issues of pollution and diminishing natural resources reawakened
the need of a more environmentally friendly means of transportation. Technologies that support a
reliable battery and the weight of the needed number of batteries elevated the price of making an
electric vehicle.[6] In 1837, Robert Davidson of Scotland appears to have been the builder of the first
electric car, but it wasn’t until the 1890s that electric cars were manufactured and sold in Europe and
America. During the late 1890s, United States roads were populated by more electric automobiles than
those with internal combustion engines.
E-Rickshaw is the most convenient and safe mode of local transportation of two or four passengers. E-
rickshaw is commonly available in India and other parts under developed & developing countries for
hiring on small rentals for limited time. Apart from E-Rickshaw, company will also make E-Rickshaw
which can carry weight up to 300 kgs.
E-Rickshaw drivers will obtain licence through which he/she can drive E-rickshaw in city. The entire
assembly and fabrication work for mfg. E-Rickshaw performed in highly automatic plants.
Rims, Tyres, Brakes, Headlight, Taillight, Horn, Turning Lights & Traction Batteries, wire Harness,
Throttle, Motor, & Controllers are purchased from the AIS approved companies. Whereas Company
will make chasis & assemble the body parts along with painting & testing of the vehicle within the
premises.
The components are made as per standard specifications and hence permit 100% inters changeability
and the chasis is fabricated accordingly keeping the optimum ground clearance and other factors in
view. Components are available in ready to use surface conditions. Automatic assembly-fixtures,
working tools and testing equipments cover the range of installations. Normally the E-Rickshaw
assembly unit with installed capacity around one lacks Nos. p.a., falls in a medium scale industry
category. But a SSI-Unit can also be started with limited facilities like:-
E-Rickshaws are three wheel battery operated vehicles, which are considered as an upgrade to
conventional rickshaws, and economically better than auto rickshaws and other fuel variants, these
rickshaws, since are battery powered have zero emission, and is often argued to be much better than
other rickshaws as they are considered almost pollution free. E rickshaws are now fairly popular
amongst Indian rickshaw drivers and has created new opportunities for people, as they require
minimum investment to earn a living. They offer huge returns in less time, and are easy to operate
and has low maintenance and running cost. A lot of variants are available these days, most of them
started as low quality products and were imported from China. These days Indian e rickshaws have
been developed offering a higher quality and better services at an equivalent cost. E rickshaws can
provide a decent income since the battery charging cost is far lower than any other fuel, new material
such as fiberglass has been introduced in them, since the material provides high strength, durability
and lighter than metals.
E–Rickshaws or Electric rickshaws have been becoming more popular in most parts of the globe since
2008. In India, e – rickshaws began to gain popularity since 2011.
As these rickshaws faced a ban by the Indian government in the capital city of Delhi, the increase in
their number failed. But, still they are widely used in most parts of the country.
On 8 October, 2014, the Ministry of Road Transport and Highways had notified the rules to regulate
the e- rickshaws by making important amendments under the Motor Vehicles Rules of 1989. In March
2015, the Parliament passed the amendments and finally, legalized the use of electric rickshaws.
Recently, the transport department decided to introduce these e-rickshaws in four major cities of
Maharashtra – Mumbai, Pune, Nagpur and Nashik.
Now, that these new age vehicles will be available on the streets soon, let’s take a look at the
advantages and disadvantages of e-rickshaws.
E-rickshaw or electric rickshaw is gaining popularity in India since 2011 due to their low cost and high
efficiency they are accepted on the Indian streets, they are still widely used in many parts of India.
E-rickshaws are now one of the preferred mode of transport in streets because of its low maintenance
cost, low fuel cost, Eco-friendly, no noise pollution, easy to drive and last but not the least livelihood,
e-rickshaw is a boon to the common man. Without putting in much physical efforts and without
investing much amount of money, the earning is quite good for an e-rickshaw driver and hence it is an
important means of livelihood for many.
These e-rickshaws consist of 3 wheels with a differential mechanism at rear wheels. Basically these
vehicles have a mild steel tubular chassis. The motor is brush-less DC motor manufactured mostly in
India and China. The electrical system used in Indian version is 48VDC can run 90– 100 km/full
charge, top speed 25 km/hour and this electric motor power ranging from 650-1400 Watts; the
battery takes 8–10 hrs to become fully charged. Basic seating capacity is driver plus 4 passenger total
5 persons.These vehicles are now started using in transporting light weight goods as e-loader. Hence
there are lots of opportunities of income, you just need to find a good manufacturing company like in
Kolkata there is Electeca which is a part of Kirti Solar Limited, a diversified group involve in
manufacturing solar and renewable energy projects. Electeca specializes in manufacturing the highest
quality E- vehicles designed and tested under the CMVR rules. Electeca has a strong team of technical
& skilled work force with hands on experience automobile industry and they have growing business
coverage in Bihar, Odisha, Jharkhand, Assam and obviously in West Bengal.
Mahindra Treo is a revolutionary new range of electric autos, e-rickshaw and cargo version. Powered
by the advanced Lithium-ion technology, Mahindra Treo offers higher savings, superior ride quality and
best in-class interior space. Ride the change with Mahindra Treo for a better tomorrow!
Specifications for Mahindra TREO-
Block diagram of E-rikshaw:
In the designed Electric Rickshaw main blocks are Battery, drive cycle, controller, DC Motor, Vehicle
body & Transmission system. The main objective is to obtain the speed by the driver, to estimate
the temperature of Motor and Controller, to estimate the sates of charge (SOC), distance travelled by
the vehicle. There is a SOC block that will estimate the state of charge of a battery, distance is calculated
by speed and time parameters for all the three Drive cycles.
Simulink model for 3-wheel E-rikshaw:
Components used in this simulink model is shown below:
1] No. of Drive cycle source - 3
2] No. of Constant blocks - 4
3] No. of Scope blocks - 8
4] No. of display blocks - 2
5] No. of product blocks - 3
6] No. of simulink-ps converter blocks - 2
7] No. of ps-simulink converter blocks - 5
8] No. of controlled voltage source blocks - 2
9] No. of temperature sensor blocks - 2
10] No. of tires - 3
11] Longitudinal driver block
12] Vehicle body
13] Simple gear
14] Battery
15] No. of Integrator block - 2
16] DC motor
17] H- bridge
18] Controlled PWM voltage block
19] Inertia
20] Differential
21] Solver configuration
22] Electrical reference
23] Mechanical Rotational reference
24] Thermal reference
25] Multiport switch
26] Bus selector
27] Voltage sensor block
28] Current sensor block
29] Controlled current source
30] Powergui block
1] Drive cycles
In this simulation, i have used 3-different drive cycle;
A] FTP75 (2474 seconds)
B] UDDS (1369 seconds)
C] SC03 (600 seconds)
2] 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.
Drive cycle is connected to a longitudinal driver, it has six ports namely velocity reference, velocity
feedback, grade, info, Acceleration, Deceleration.
VelRef is given by the drive cycle data and VelFdbk is given by the output of the motor. These two will
get compare and the acceleration or deceleration output will be given to the motor controller. Accelcmd
is given the PWM generator block and deccelcmd is given to the regenerative port of the h-bridge
which uses to generate regenerative braking. Info is used to get any other data from a longitudinal
driver block. The grade is to give the input of gradeability to the driver block. This block helps to
generate the driver's conditions of the vehicle using the drive cycle block.
3] Motor and Controller:
i] DC motor (PM brushed type motor)
This block represents the electrical and torque characteristics of a DC motor includes Thermal port to
sense the temperature of 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 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 flow 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.
Motor parameters:
TheMotor controller will get input from the longitudinal driver. Its tasks is to control the speed of the
motor and drive according to the input of the driver.
Majorly motor controlled we designed had two main parts named PWM voltage generator and H-
Bridge.
Input1 is getting from the accelmd of a longitudinal driver and it is given to a controlled voltage source
block where it is input to the controlled PWM voltage.
Controlled PWM voltage will generate a PWM signal in such a way that H-bridge will generate the
required voltage to operate the DC motor for the given driver input. PWM voltage block negative
reference and REF are grounded and REF of H-bridge respectively. H-bridge is a motor controller that
has IGBT components
Aligned in the shape of H and will operate only two at a time respectively to the input of the signal
from the PWM block. When deceleration occur this H-bridge will give an output from the positive and
negative terminals of it. These negative & positive terminals are later connected to the DC motor and.
battery. All these components are the simscape electrical components so they need a connection
tothe solver configuration block which helps to solve the simulation.
ii] Temperature Sensor
Temperature Sensor is used to mesure the temperature of H-Bridge and Motor.
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.
iii] Controlled PWM voltage source
The value of the Output voltage amplitude parameter determines amplitude of the output voltage.
The Controlled PWM Voltage block represents a pulse-width modulated (PWM) voltage source.
Electrical input ports — The block calculates the duty cycle based on the reference voltage across its
ref+ and ref- ports. This modeling variant is the default.
PS input — Specify the duty cycle value directly by using an input physical signal port.
where,
Vref - is the reference voltage across the ref+ and ref- ports.
Vmin - is the minimum reference voltage.
Vmax - is the maximum reference voltage.
Parameters of controlled PWM voltage source block:
iv] Power converter: H-bridge
H-Bridge is used as a DC-DC converter.
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.
If the REV port voltage is greater than the Reverse threshold voltage, then the output voltage polarity
is reversed. If the BRK port voltage is greater than the Braking threshold voltage, then the output
terminals are short circuited via one bridge arm in series with the parallel combination of a second
bridge arm and a freewheeling diode. Voltages at ports PWM, REV and BRK are defined relative to the
REF port. If exposing the power supply connections, the block only supports PWM mode.
Block parameters of H-bridge:
v] References
1] Electrical Reference: Used to ground the all the electrical connections.
2] Mechanical Rotational Reference: Used to ground all the mechanical rotational parts.
3] Thermal Reference: Used to ground the thermal sensor.
vi] Solver configuration
It is used to defines the solver settings to use for simulation.
4] Battery
State of charge- SoC (%):
SoC is the percentage or level of battery presents after certain travel or consumption of battery charge
by the vehicle. In the designed vehicle battery charge or SOC is calculated by the giving it to the rate
transition and then to gain where 1/(nominal battery capacity) then to a discrete-time integrator and it
will get minus from the 1 as it is considered a 100% of battery and it is multiplied with 100 to get
percentage of battery. The majority of blocks are simscape blocks where physical to simulink converter
is used to convert the physical signal from simscape block to simulink signal.
Battery parameters:
5] Vehicle body and Transmission
The gear output is given to axels of Rear tires, in the circuit it is shown that gear is connected to Rear
wheels and front tire is free to rotational motion, thus vehicle moves forward. N is the normal force
caused by the tires and it is given to the vehicle body normal force port. The vehicle body has an H-
Hub, S- Tire slip, N- Normal force, A- axel connection, wind velocity, inclination angle. The tires hub is
connected as a common node to the vehicle body. The vehicle body wind velocity is connected to a
constant block and the beta-inclination angle is connected to another constant block where we can
assign wind velocity and inclination angle as per requirement. Velocity is the output port where we can
get at which speed the vehicle is moving. The velocity is taken out to the get the distance travelled
and state of charge.
A] Vehicle body
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. Duty cycle is set by the input value. Right-click the block and select Simscape->Block choices to
switch between electrical +ref/-ref ports and PS input u to specify 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 value equal to the averaged PWM signal.
No.of Wheel per axle are 2 (Rear Wheels), where as front wheel is free to rotate.
Block parameters of vehicle body:
B] Wheels
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.
Connection A is the mechanical rotational conserving port for the wheel axle. 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. 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. Connection S is a physical
signal output port that reports the tire slip. Optionally expose physical signal port M by setting
Parameterize by to Physical signal Magic Formula coefficients. Physical signal port M accepts a four
element vector corresponding to the B, C, D, and E Magic Formula coefficients.
Block parameters of wheel:
C] Simple Gear box
Gear Ratio, Represents a fixed-ratio gear or gear box. No inertia or compliance is modeled in this
block, We can optionally include gear meshing and viscous bearing losses. Connections B (base) and F
(follower) are mechanical rotational conserving ports. Specify the relation between base and follower
rotation directions with the Output shaft rotates parameter. Optionally include thermal effects and
expose thermal conserving port H by right-clicking on the block and selecting Simscape block choices
to switch between variants. Output shaft rotates in in same direction of input shaft. Base is connected
to the Motor shaft and the follower is connected to the Rear wheel derive.
D] Inertia
The block represents an ideal mechanical rotational inertia.
The block has one mechanical rotational conserving port. The block positive direction is from its port to
the reference point. This means that the inertia torque is positive if the inertia is accelerated in the
positive direction.
https://drive.google.com/file/d/17MlLQsIdTr5ba-YHUhL5u1EhMV73DPGV/view?usp=sharing
1] For 1st drive cycle source , FTP75 (2474 seconds) :
simulink model is shown below,
On running the above simulation for 2474 sec, following results are obtained:
1] For battery output is shown below,
a] Battery soc (%) used,
Battery soc reduces from 100 to 99.4%.
b] Battery current used,
c] Battery voltage used,
Voltage drops from 102.5 to 98.55 v .
2] Power consumption( W)
Power consumed during simulation is 369.3 w
3] Distance covered (km):
Disatance covered by e-rikshaw for 2474 sec is 10.43 km @45kmph.
4] Temperature:
Motor temperature gradually increses to 10,000c where as h-bridge temperature
rises from 0 to 800c.
5] Voltage sensor o/p :
6] Current sensor o/p:
2] For 2nd Drive cycle, UDDS (1369 seconds):
a] Battery Soc reduces from 100 to 99.5.
b]
At end of the simulation time 1369 sec current reaches to 0. Initially Current reaches from
0 to 235 for tome 170 sec.
c]
Voltage level drops from 102.1 to 99 volt from 160sec - 1369 sec.
d]
Power consumption for given driving cycle is 271.4 W.
e]
Distance covered/travelled by e-rikshaw is 7.93 km @ 45 kmph.
Yellow liine represents the motor temp. and blue line represents the h-bridge temp.
3] For 3rd Drive cycle, SC03 (600 seconds):
Simulink model is shown below;
Simulation time is 600 sec. On running this simulation we get the following results,
a] Battery Soc falls down from the 100- 99.72 %.
b] Current drawn by the is shown below, Initially from 0 to 240 sudden overshoot occurs
for time 10 sec. After this current comes to 25 for next 30 sec. At the end of the
simulation period Current becomes -ve gives the value nearly equals to -10.
c]
voltage drops below 99.5 v during the starting of simulation. At a time of 180 sec,
voltage rises abobe the 101.5 volt. At time 600 sec voltage reaches to 99.9 v.
d]
For the third driving cycle motor temperature rises drastcally compare to h-bridge
temperature.i.e motor temperature reaches to above 4000c.
e]
In this simulation distance covered by e-rikshaw is 5.117 km @ 45 kmph.
e]
Power consumption by battery is 175.9 w.
Maximum distance is covered by using 1st driving cycle for the given simulation.