Electric vehicle charging from solar panels and public electricity.
Using public electricity and solar panels for easy and hassle-free charging of electric vehicles is an interesting solution to the problem of non-availability of electric vehicle charging stations.
Electric vehicle charging station from solar panels and public electricity.
This article is a part of educational technology exposure program. The program aims to recognize and reward innovation from engineering students and researchers around the world.
The primary reason people dislike electric vehicles is the unavailability of charging stations. Charging stations like petrol stations are not available everywhere. There is always the fear of what will happen if the vehicle battery runs out. People are worried about more direct and faster modes of travel in our country instead of saving the earth from the ill effects of pollution.
The mission specifically offers with a easy way to make charging stations extra accessible. The solution involves using public electricity and solar panels for easy and hassle-free charging of electric vehicles. This project includes a scaled-down prototype.
Introduction
A universal charging station charges vehicles from different companies with different batteries with different charging capacities, increasing demand for EVs and ensuring reliability. An easy way to acknowledge this concept is that the charging mechanism takes into play by simply varying the current and voltage to deliver the specific power required by the battery for fast charging. Regulators maintain regulated power distribution.
This model is a scaled-down version of reality in which the systems operate exactly. The setup is constantly monitored to ensure that it is a foolproof setup and there is no possibility of power theft. The device is an IOT based programmable, secure interface that provides a plug-in to the customer for a fee when required.11
Solar energy is a source of sustainable energy and it is an infinite and clean source of energy which is free and environment friendly. Hence, it is highly efficient and free from environmental pollution. The alarming situation of global warming will lead to full adoption of renewable energy based transportation systems.
However, their sustainable deployment at mass level is a challenging task. To overcome the above dilemma, a better solution is to charge electric vehicles using distributed solar energy, resulting in net-zero emissions. Solar energy enables a quick move to a green initiative.
The latest technology, including fast charging and better running, is leading to the increasing use of electric vehicles. There is always a suspicion in everyone’s mind as to what will happen if the vehicle battery runs out. This indirectly leads to choosing a conventional vehicle instead of going pollution-free as it satisfies the needs.
In 2020, India was the fifth largest automobile market, with sales of 3.03 million units across the passenger and commercial vehicle segments. It is the seventh largest producer of commercial vehicles in 2019.
This chart exhibits how much carbon dioxide is emitted in a given year.
โข These figures are based on ‘production’ emissions (ie, emissions from the combustion of fossil fuels within the country’s borders).
โข These figures appearance specially at carbon dioxide emissions โ now no longer general greenhouse fueloline emissions.
โข Annual emissions may be primarily influenced by population size โ we present per capita figures above.
The prototype listed in this report is a portable charging station that is located on roads at frequent and regular intervals. This device is placed on street lamp posts, takes electricity from them and runs it through a parallel connection and charges a plugged in vehicle.
The device is an IOT based programmable, secure interface that provides a plug-in for a fee when the customer needs it.
Methods and material
The following components are used in EVCS as set out in the procedure circuit and respective pin diagram. The Arduino, the primary controller of the prototype, is explicitly programmed and controls the HC05, NEO 6M and relay.
ย ย ev-charger-operation ย ย Figure 2: Sequence of operation
The above figure shows the sequence of steps involved in the working of EVCS with respective components. 2 relays mechanically transfer among AC electricity deliver and sun electricity.
Arduino Uno
Arduino Uno is an open source microcontroller based on Microchip ATmega328P microcontroller and developed by Arduino. An Arduino board has digital and analog pins that can be interfaced to various expansion boards (shields) and other circuits. The board has 14 digital I/O pins (six PWM output capable), 6 analog I/O pins. They are programmable with Arduino IDE (Integrated Development Environment).
Bluetooth Module (HC05)
The Bluetooth SPP (Serial Port Protocol) module is planed for obvious wi-fi serial connection setup. The HC-05 Bluetooth module can be used as a master or slave configuration, making it an excellent solution for wireless communication. This SP Bluetooth module is a fully qualified Bluetooth V2.0+EDR (Enhanced Data Rate) 3Mbps modulation full 2.4GHz radio transceiver and baseband.
Relay
A relay is an electrical device that acts as a switch. It consists of sets of input terminals and output terminals for single control signals or sets of multiple control signals and operating contact terminals. A relay switch can have any number of contacts in multiple contact forms, such as normally open circuits and normally closed circuits or combinations of both circuits. It can be easily turned on or off and whether the current goes or not, and the relay can control it with low voltages of 5V connected to the battery provided by the Arduino pins.
NEO 6M GPS Module
The NEO 6M GPS module is a satellite navigation device capable of receiving information from 24 GNSS satellites orbiting the Earth and then calculates and transmits the geographic position of the device according to latitudes and longitudes.
Solar panel
A solar panel is a group of photovoltaic cells (PV cells) placed in a frame for installation. The renewable energy of solar panels in the form of sunlight converts it into electricity and then stores the electricity in a specific battery, which can then be used to power loads.
Solar charge controller
A forward biassed n-channel MOSFET is used to stop the current from the battery to the solar panel. A zener diode (10v) protects against low voltage, which sends a positive feedback, turning on the relay. A zener diode (15v) protects against over-voltage, which sends negative feedback, turning off the relay. Another n-channel MOSFET is used to protect the battery from overcharging by turning off the relay.
Solar charge controller
Digital Energy Metre
Electricity metres work by continuously measuring the magnitude of the instantaneous voltage and the magnitude of the current and finding the product of these to give the instantaneous electrical energy, which is then integrated against time to provide the energy used for charging.
Methodology
The GPS module, Bluetooth module and relay are all attached to the Arduino in a specific way. The main purpose of this model is to block and reverse the flow of electricity using a relay with the help of Bluetooth interface.
The prototype is designed to be placed at the bottom of the street lights. The electric wires running in the street lights carry 220v, the same as we receive in our homes. Using this concept, charging of EVs takes place outside with 220v voltage.
Additionally, a solar panel is added, which is used to extract solar energy and convert it into usable electricity. The panel has its associated solar charge controller, which controls the voltage flow into the battery. The vehicle to be charged is scaled and assumed to be 12v and a 10Ah battery. A solar charge controller extracts energy from the sun’s solar radiation, reduces the voltage and supplies it to the battery accordingly.
The EVCS has two relays that automatically switch to distribute power. A light sensor is installed to detect the presence of sunlight. In the absence of sun, relay 1 is turned off and relay 2 is activated, which can be used for power distribution.
During the day, in bright sunlight, users can use solar power or conventional electricity from the grid. 2 relays present can be activated based on requirement. The EVCS consists of an Arduino connected to a GPS module, relays and a Bluetooth module. Two possible routes are described below.
Case 1: Solar charging โ Relay 1
In the presence of sunlight, relay 1 is active and can be turned on or off. Solar radiation is converted into electricity and passes through a solar charge controller. A solar charge controller is a voltage and current regulator that prevents batteries from overcharging and overheating. It regulates the current and voltage from the solar panels and protects the battery by preventing over-voltage, under-voltage and back current. Relay 1 is turned on, and charge begins to flow from the solar panel to the battery. Relay 2 is inactive at this time.
Electric Grid Charging โ Relay 2: (Case 2)
Power from the street pole directly enters relay 2 (active relay) and relay 1 is inactive. For charging using a home adapter the user plugs in his car and electricity from the 220v line passes through and charges the vehicle. When the charging sequence begins, it is ensured that power is supplied from only one source. The responsible relay is specifically turned on. Both relays cannot turn on at the same time.
Example:
An electric vehicle is low on battery; The driver searches for the nearest charging station on his phone. Charging stations are provided with a unique location tag and are positioned by GPS. The NEO 6M GPS module actively tracks 24-30 satellites and sends coordinates to the phone. Then the coordinates are decrypted, and the exact location is shown on the map.
The vehicle stops at the desired parking spot and detects the EVCS. Users can choose between solar charging (if the relay is active in the presence of solar radiation) or electric grid charging. The charging wire is plugged into the outlet of the EVCS, or in the case of solar charging, the charging wire is connected to the vehicle’s inlet. A plug-in socket has a 220v line drawn from a street lamp.
Customers are certified as registered owners of electric vehicles with the collected database. Credentials are entered and access is granted. Bluetooth is turned on and an interface linked to the relevant EVCS is created, allowing the charge to flow. Engaging and deactivating the power supply is done through a mobile app. Once engaged, the Arduino recognizes the user as a trusted source and sends information to the relay. The relay then closes the circuit, providing current flow.
A digital energy metre is placed and the power consumed is constantly monitored. Customer information is recorded and stored on the server and the number of units consumed is calculated along with the cost per unit. After charging is complete, the circuit is deactivated, and the relay turns off the current flow.
An energy metre tracks electricity usage and collects data, which is then sent to the customer’s phone. After activating the supply or completing the payment, the payment gateway is opened and the transaction is done.
This completes the whole procedure of charging an EV. Charging of EVs has been made easy, hassle free and
safe This ensures that the electricity is not stolen and only used to charge the respective EVs.
Results and discussion
Solar Panel โ 18V,
Battery โ 12V 10Ah,
Power source 220V, 50Hz AC.
Note: The solar charge controller goes down
Voltage 18V to 12V.
P= Power, V= Voltage, I= Current
P = V*I
P = 12*10
P = 120 watts
So, it takes time to charge from 0 to 80%
It is 1 hour. (When 10A is supplied)
Note: Input = 220V AC, Charge Adapters a
Nominal output of 12V and 5A.
P = V*I
P = 12*5
P = 60 watts
So, the time required to charge from 0 to 80% is 2 hours. (5A supplied) Total theoretical time to charge from 0 to 100% is approximately 1 hour and 15 minutes for solar charging and 2 hours 30 minutes for standard charging.
The following experiment of plugging the EVCS into a single-phase AC power supply was performed using a temporary onboard 9V battery that powered the Arduino. After the current started to flow, the relay, an electrical switch, blocked the current from flowing through the output terminal. Currently, this is the inactive status of EVCS. A relay acts as a circuit breaker. When plugged in through EVCS, none of the equipment will work because the current flow is interrupted.
To initiate the mechanism and circuit flow, an Android application is used. This app allows you to connect to the Bluetooth module placed in the setup. First, a reliable and validated interrelation is established in the middle of the user and the host. The phone is verified with a pre-registered stored database before using the app.
User Bluetooth and host Bluetooth are paired and the relay can be controlled using various functions in the app. The user then locates the EVCS switch key within the app and toggles it on.
At this moment, information is received from the phone and the interaction between the phone and the EVCS is set up. The Arduino takes the Bluetooth information, processes it and then matches it with an algorithm running on the Arduino and sends an output signal to the relay. Then the relay is turned on, and current begins to flow. The entire process of current flow is monitored and the usage time is recorded. A plug-in device that is a battery charger now receives the current required for charging.
Relay, bluetooth and arduino interface is smooth and secure and the necessary work is accomplished.
Archetype
Figure 4: AutoCAD Prototype Figure 5: Making Stereotype
A archetype of the EVCS was produced using AutoCAD software and finally incorporated into a working scaled-down model. All connections and pin configurations with Arduino and various components are shown in Figure 6.
ย Figure 6: Pin Diagram, ev-charging-pin-diagram
Interpretation
The setup below works efficiently and smoothly without any errors or unnecessary functions. Charging of the battery took place, and the time taken along with the energy consumption was recorded. Monitoring the entire system throughout the process ensures no defects or wastage of power. There are no power fluctuations, and the voltage is maintained and controlled with integrated circuits and a microprocessor, which plays a significant role in ensuring regulated voltage and current flow. Several more modifications are needed to make this prototype secure and proof-of-stealing. Battery safety, transaction details with the use of a particular unit will work smoothly.
Fast charging capability with both solar and 220v power grid energy sources should be adopted to reduce the time required for charging. The entire system is a scaled-down model as all tests are performed for a small Li-Ion battery of 12V and 10Ah. Charging time is approximately 2 hours 30 minutes with adapter and 1 hour 15 minutes with solar charging. The device now operates with limited sequence and instructions and is powered by a switching circuit which is taken care of by a relay. Finally, device switching on and off is secure and follows a set of protocols for the interface between the phone and the EVCS prototype.
Sources
[A]. International Journal of Scientific Engineering and Research (IJSER) ISSN (Online): 2347-3878
[B]. Development of rapid charging system for EV batteries, Latest Technology and Engineering (IJRTE), ISSN: 2277-3878, Vol-7, Issue-6S, March 2019.
[C]. Wireless Communication Using HC-05 Bluetooth Module Interface with Arduino, ISSN: 2278 โ 7798, International Journal of Science, Engineering and Technology Research (IJSETR) Volume 5, Issue 4, April 2016.
[D]. Real-Time Vehicle Tracking System Using Arduino, GPS, GSM, and Web-Based Technologies, International Journal of Science and Engineering Applications Volume 7โIssue 11,433-436, 2018, ISSN: -2319โ7560.
[E]. Electric Vehicle, Battery Charger, Charging Station and Standards Research Journal of Applied Sciences, Engineering and Technology 7(2): 364-373, 2014 DOI:10.19026/rjaset.7.263 ISSN: 2040-7459; e- ISSN: 2040-7467 ยฉ 2014 Maxwell Scientific Publication Corporation.
[F]. Suarez, Camilo and Martinez, Wilmar. (2019) Fast and Ultra-Fast Charging for Battery Electric Vehicles -A Review. 10.1109/ECCE.2019.8912594.
[G]. Real-Time Vehicle Tracking System Using Arduino, GPS, GSM, and Web-Based Technologies, International Journal of Science and Engineering Applications Volume 7โIssue 11,433-436, 2018, ISSN: -2319โ7560.
[H]. Design and implementation of 12v automatic battery charger
[I]. Electric Vehicles Charging Technology Review and Optimal Size Estimation, Journal of Electrical Engineering & Technology (2020) 15:2539โ2552
About University Technology Exposure Program 2022
Wevolver, in partnership with Mouser Electronics and Ansys, is excited to announce the 2022 launch of the University Technology Exposure Program. The program aims to recognize and reward innovation from engineering students and researchers around the world. Learn more about the program here.
