NSIT SOLAR CAR CONCEPT

NSIT Solar Car Concept is a non-profit organization, founded in 2007, which aims to build a solar powered race car and represent INDIA on an international platform. It is a student run initiative and the primary goal is to make solar power practical and affordable. The team is dedicated to build a car that demonstrates the viability of alternate sources of energy and innovation in mechanical and electrical technology.

The team is currently working on its third car. It is one of the only two university level teams in India that build Solar Electric Vehicles (SEVs) and the only one that has secured a podium position at an international event.

The American Solar Challenge (ASC), previously known as Sunrayce, the American Solar Challenge, and the North American Solar Challenge, is a solar car race across the United States and Canada. In the race, teams from colleges and universities throughout North America design, build, test, and race solar-powered vehicles in a long distance road rally-style event. ASC is a test of teamwork, engineering skill, and endurance that stretches across thousands of miles of public roads.

The 2014 edition will have a FSGP closed circuit 3-day event and then a cross country 8-10 day race that will test the endurance and engineering of the cars and their internal systems.

THE VISION  Provide an international platform to represent our

country and institute with pride. To make an advanced solar electric vehicle. To research about solar power and technologies

and to make it more efficient so that it can turn into a sustainable energy source.

Promoting innovative, environmentally friendly technology as well as creating a positive learning atmosphere for student body involvement

General public awareness about the green technologies available to the world, so that young people they grow to be environmentally friendly.

PREVIOUS CARS ADVAY 1 was one of the cheapest solar cars in the world and

cost a fraction of the other cars participating in the South African Solar Challenge 2009It secured 2nd position in its category and stood 3rd in the overall rankings in SASC 2009.The car was showcased at multiple exhibitions across the country.

ADVAY 2 was the second solar car of the team. It was designed and built for the World Solar Challenge. It was showcased at the National Auto Expo 2010, New Delhi and remains one of the only few student projects to be showcased at the grand event.

ADVAY 3

The team aims to make their third vehicle for the WORLD SOLAR CHALLENGE and the AMERICAN SOLAR CHALLENGE It will be representing INDIA and will showcase our engineering excellence and the effort to work with non-conventional sources of energy.

Preliminary designs(subject to massive change) are shown in the next two slides.

ADVAY 3 DESIGN

Why should you be a part of the team.

Research opportunities in the field of solar energy.

Innovation in the electrical and mechanical systems.

First hand experience of building a solar car and being a part of a legacy.

 

Solar Cars- Present Problems

Low Energy Density On a clear day, energy from sunlight comes to Earth at a density of about

1,000 watts per square meter of area . This means if you had a one square meter solar panel that worked at 100 percent efficiency, you could run a hair dryer with it. The engine in a typical car develops about 50 kilowatts of energy. Your perfect solar panel would have to measure approximately 90 square meter to produce this much power. We have only about 6 square meters to tackle the same problem.

Low Efficiency Commercially-available solar cells that produce electricity from light do not

have 100 percent efficiency, but instead top out at around 18 percent. To compensate for the reduction in energy due to low efficiency, you'd have to make your solar panel bigger.A Gallium Arsenic cell has a 30% efficiency but the costs are too high for us to consider it as an alternative.

All this leads to the cars having High Costs and an Impractical Design And herein lie the research opportunities.

Research Opportunities in the field of solar power

Nanowire Solar Cells Practically, the efficiency of solar cells has to be increased and simultaneously the costs have to

be reduced. Nanowires are a promising material system to realize this. Due to the small size of nanowires, different materials can be more easily combined compared to bulk systems, and more sophisticated tandem cells could be fabricated. In addition, light can be more efficiently absorbed by using conical nanowire shapes, and in radial nanowire geometries the optical absorption path length can be disentangled from the charge separation distance allowing more design freedom. This all may enhance the efficiency of solar cells.

  SPECTRAL CONVERTERS Lanthanide Ions, Quantum Dots and many luminescent solar concentrators are used as spectral

converters. a) Quantum Dots to Enhance Solar Spectrum Conversion Efficiencies for PV Cells Silicon-based

photovoltaics typically convert less than 30% of the solar spectrum into usable electric power. This study explores the utilization of CdSe based quantum dots as spectral converters that absorb the under utilized UV portion of the solar spectrum and fluoresce at wavelengths near the band-gap of silicon-based solar cells. A flexible 1 mm thick thin-film structure that contains an array of microfluidic channels is designed and fabricated in polydimethylsiloxane (PDMS) using soft-lithographic technique

RESEARCH IN POLYMER SOLAR CELLS A polymer solar cell is a type of flexible solar cell made with polymers, large molecules with

repeating structural units, that produce electricity fromsunlight by the photovoltaic effect. Polymer solar cells include organic solar cells (also called "plastic solar cells"). They are one type of thin film solar cell, others include the currently more stable amorphous silicon solar cell. 

ADVAY – COVERAGE IN MEDIA

ADVAY – COVERAGE IN MEDIA

ADVAY – COVERAGE IN MEDIA

ADVAY – COVERAGE IN MEDIA

UNIVERSITY OF MICHIGAN’S MULTIPLE AWARD WINNING CAR.

DESIGN OVERVIEW

By Electronics & Electrical DepartmentNSIT SOLAR CAR TEAM

Basic Electrical Design

Solar Panel Array

DC-DC Converter, MPPT

Battery Managment System and batteries Motor Controller

Motor

Transmission of power to wheels

Instrumentation- Data transfer: speed,

rpm, etc.

Instrumentation : battery charging and output

current/voltage status

Electrical System protection

Powering a Car by Solar Panels

Solar cars utilize sun’s energy. Solar array, a combination of solar cells, collects sun’s energy and converts it into usable electrical energy.

This usable electrical energy is stored in batteries via maximum point power trackers that convert the energy collected to system voltage.

Once batteries are charged, motors can be run and controlled by the use of a motor controller that adjusts the amount of energy flowing to the motor according to the throttle.

The Internal Process

ELECTRONIC & ELECTRICAL COMPONENTS

A solar car majorly comprises of the following electronic and electronic components: Solar Panels/Solar Cell Arrays Maximum Power Point Trackers (MPPT) Battery and Battery Management Systems Motor and Electronic Motor Controller Instrumentation & Telemetry components General Electrical and safety components like

fuses, MCBs, switches, etc.

SOLAR ARRAYS A photovoltaic array or solar array is a linked connection of

solar panels which in turn is formed by joining solar cells. Solar array is mounted on upper part of chassis of the solar car which converts the incoming solar energy into electrical energy.

The number of cells to use depends on the size and allowable solar area as per rules of a particular competition.

Maximum Power Point Trackers

Solar array voltage (i.e. voltage produced by the solar array) must be equal to system voltage of the motor for optimal working of motor. Generally, it is difficult to match these voltages accurately due to random errors and Maximum Power Point Trackers come to rescue. MPPTs allow the system to run as efficiently as possible by sampling the output of the cells and apply the proper resistance (load) to obtain maximum power for any given environmental conditions. Basically, they extract the maximum possible power from solar array.

The circuitdiagram for a MPPT

BATTERIESThe batteries store energy from the solar array and make them available for the motor’s use. While choosing the batteries, we need to consider the following points: System voltage required Maximum permissible ampere-hour rating Time taken to charge the batteries Weight and Size CostBatteries that are commonly used in solar cars are Lead-acid batteries, Li-ion batteries, Ni-MH batteries, Ni-Cd batteries, Flooded-cell batteries and Gel-cell batteries.

Lead Acid Ni-Cd Battery Li-Ion Battery NiMH battery

Motor & Controller Motors, powered by batteries, run the solar car. Motors generally employed in solar cars are either AC motors or brushless DC motors. We intend to use brushless DC motors because of its following advantages: DC motors can be overdriven for short periods of time which

is great for short burst accelerations. DC motors can assimilate the ‘Regen’ feature of AC motors

so that charging is possible during breaking mode of operation of motor.

Efficiency of brushless DC motors is 95-98%. DC motors are cheaper than AC motors.

Controller is an electronic device that controls the amount of power delivered to electric motor according to the signal from the potentiometer connected to throttle pedal.

INSTRUMENTATION One of the most important pieces of instrumentation is a

state-of-charge meter. A state-of-charge meter gives information about system voltage, amp draw, battery energy remaining, and estimates the how much time remains until the battery is out of energy.

The E-Meter is the do-it-all in instrumentation. Another instrument that may be useful is a speedometer. Instead of using a regular speedometer drive, use magnetic contact speedometers, found in many sports equipment stores. This option does not add drag to the solar car. To ensure that batteries are running properly, a voltmeter is connected to each of the batteries. A failed battery may show the proper voltage when the car is not running, but while the battery is under load, the voltmeter will show a lower than normal battery voltage.

Nowadays, advanced controllers are available that not only can control the power delivered to the electric motor but display the number of ampere-hours left in the battery, voltage of the battery, speed of the electric motor and telemetry to the driver as well, thus reducing off-road time in analysis.

Telemetry System The Telemetry system includes all the

communication and feedback mechanisms that are employed in the car for better functionality and for the ease of the driver and the crew to monitor the efficient and safe working of the solar car.

These include: Wireless Communication System Solar Charge controller Headlights & Tail lamps GPS System

Circuit Protection

Fuses(over current)

Diodes(reverse current)

Metal Oxide Varistors - MOV(over voltage)

In series with circuit

In series with circuit

In parallel with circuit

Stage 1 – DESIGNING IN CAD

The concept will first be visualized by making their 3D CAD drawings in the following 3D modelling softwares:

Unigraphics NX Solidworks

Stage 2 – ANALYSIS USING SOFTWARES

After succesful 3D modelling of the concept car the model is simulated using analysis softwares to check its feasibility and stability. Following softwares are used for simulation:

ANSYS SHARK

DESIGN PROCESS

First of all a 3D model of the concept will be modeled in NX.

After successful drawing of the car the 3D file will be exported to Ansys for analysis part. Meanwhile Suspension simulation will be carried out in Shark FX.

If found troublefree the model will be finalized and the Manufacturing of the concept will begin, otherwise the 3D drawing is modified as per the needs.

MECHANICAL SYSTEM

(Separate Presentation)- Disjointed with the main presentation

Mechanical Systems

1) Suspension

2) Chassis and aerodynamics

3) Brakes

4) Steering

SuspensionA system which forms an interface between the road surface and the car chassis

It is present to ensure that the tires stay in constant contact with the road.

Suspension is responsible for contolling the force distribution on the four tires, and also thus influences steering characterstics of the car.

Uses

Road isolation

Road holding

Cornering

Types of suspension in solar cars

1) Double wishbone2) Trailing arm

ChassisGeneral purpose of chassis-The purpose of a motorcar chassis is to connect all wheels in a structure that will not bend or sag under force. The structure should absorb all loads applied to it without deflecting.

Solar car chassis are supposed to be light weight

Safety is a major issue and the chassis should ensure driver for the race

Types of chassis in solarcars

Space frame

Monocoque

Materials

Characteristics of material to be chosen

For space frame Aluminum 6061 Steel 4130

For monocoque Carbon fiber

Analysis will be done through Ansys

Important features of chassis

A stiff structure with minimal deformationCenter of gravity position and position of various Elements.Safe and space efficientRoll cageCrumble zone

AerodynamicsWhy aerodynamics in solar vehicles

Our aim-1)Reduce aerodynamic drag(most important)2)Reduce coefficient of lift

What is drag?

Types of drag1)Separation drag2)Skin friction drag3)Pressure drag4)Induced drag