Project

# Title Team Members TA Documents Sponsor
3 Smart Interface for ECEB Research Solar Panels
Texas Instruments Best Project Award
Dillon Vadgama
Douglas Lee
Sachin Reddy
Shaoyu Meng design_document3.pdf
final_paper1.pdf
presentation1.pdf
proposal1.pdf
video
# Problem

In 2018, a fire broke out on the roof of a Walmart in Beavercreek, Ohio due to Tesla’s unmaintained solar panels suffering from hotspots. These hotspots resulted in the cracking of the back sheets of the solar modules and compromising their electrical insulation. There was no protection system to detect this type of unwanted behavior and shut down the system before a fire broke out. As a result, Walmart sued Tesla over the flaws present in their solar panels.

Our very own ECE Building has a roof of 60 solar panels used for research; however, there are no protection interfaces between the solar panels and their connections to the power inverter. A smart interface box attached to each solar panel that monitors system behavior and has the ability to shut off the entire operation could help prevent a disaster like Walmart’s.

This project was initially pitched by Professor Arijit Banerjee and generated interest from several students. After a meeting with Professor Banerjee and David Null, two teams working on two separate projects related to the ECEB solar panels were created. It was decided that our group (Dillon Vadgama, Doug Lee, and Sachin Reddy) will be working on the Smart Interface Box for the ECEB research panels. The other students will be working on another project relating to the set of solar panels providing the building with power.


# Solution Overview

Our solution for monitoring and controlling our solar panels will be a smart interface box mounted directly to the solar panel. Electrically, the interface box will be connected directly to the output of the solar panel and will have the ability to configure how many cells will be connected to the power inverter (32 cells, 64 cells, or 128 cells). The system will be powered from an isolated 12V supply and an Ethernet interface will allow users to configure and monitor the solar panel through a server/PC. Because the power generated by the solar panel will be running through the smart interface box, we will have the ability to detect overcurrent/overvoltage conditions and disconnect the solar panel if necessary. Lastly, connections on the interface box will be available to attach thermocouples. Doing so will allow us to measure temperatures on different parts of the solar panel and disconnect the solar panel to prevent a hotspot disaster.

The interface box will have the following key features:
- The output of the interface will be configurable to be connected to either 32 cells, 64 cells, or 128 cells.
- The output of the interface box will be protected from overvoltage and overcurrent.
- An onboard microprocessor will allow for communication and measurement of system parameters over an ethernet connection.
- The box will be powered from an isolated 12V PSU.
- Should the 12V power supply fail, the output of the interface will be disconnected from the solar panel.
- Onboard LEDs will indicate the operational status of the panel and interface.
- When the system is not communicating via Ethernet, the configuration of the interface can be controlled manually via onboard - switches.
- The enclosure of the interface will be weather-proof along with any cable jacks used.
- An option to integrate thermocouples with the system will be available.


# Solution Components

## Switching Subsystem

- Contains switching components responsible for connecting different sections of the solar panel (32 cells, 64 cells, or 128 cells) to the output or disconnecting the solar panel altogether.
- The switching configuration will be controlled by the Processing Subsystem.

## Electrical Monitoring Subsystem

- Connects directly to the output of the switching subsystem and is responsible for measuring current and voltage.
- The subsystem has two outputs: one that communicates voltage/current data to the Processing Subsystem and another that passes power generated by the solar panel to the output of the interface box (and into power inverter).

## Temperature Monitoring Subsystem

- Contains all of the circuitry necessary to extract temperature data sourced from thermocouples that will be mounted on various areas of the solar panel.
- This data will be sent to the Processing Subsystem for further analysis.

## Manual Switches

- In case of a loss of connection to the internet and the server is unable to access the interface box, there will be manual switches mounted on the enclosure to control the configuration of the solar panel.
- These switches will not affect the configuration of the solar panel if the Ethernet Interface is in already in use.

## Processing Subsystem

- An internal microcontroller (most likely an ATmega328P) will be used to communicate with and control other subsystems present in the interface box.
- Detects overcurrent/overvoltage conditions using data sent by the Electrical Monitoring Subsystem.
- Detects hotspots and overheating using data sent by the Temperature Monitoring Subsystem.
- Controls the Switching Subsystem to set the output configuration the solar panel or disconnect it altogether if a failure condition is met.
- Packages and sends relevant data and receives configuration commands from the user through the Ethernet Interface.
- Reads the switch states from the Manual Switches to control the configuration of the solar panel if an Ethernet connection has not been established.

## Ethernet Interface

- Facilitates communication via Ethernet between a server/PC and the microcontroller installed in the interface box.
- Allows the command, control, and monitoring of the solar panel to take place.

## LED Display

- Several LEDs will be present to show information about:
-- Whether or not the interface box is active
-- The current configuration of the solar panel, or
-- Whether or not an Ethernet connection is active.

## Power Subsystem

- Regulates the 12V supply into voltage levels suitable to power all of the above subsystems.

## Software

- Receives data output through the Ethernet Interface and stores the information in a database of some sort.
- A python based GUI will be able to extract, transmit commands, and display the data, providing a user-friendly experience.
- Must be Windows compatible.
- Both the database and the GUI should be secured to prevent unauthorized users from controlling the solar panels.


# Criterion for Success

Our solution will be successful if it can accurately monitor a solar panel’s power output and temperature while simultaneously reporting this data to an external server. A GUI type interface should display output data from the interface box and allow the user to configure the solar panel remotely. In the case of a loss of connection to the internet, the interface box will be controlled by built-in buttons on the box. Additionally, the interface box will be a success if it can realize all of the items listed in the Key Features section above.

We aim to build a weather-proof device that can use an Ethernet LAN connection to then access a server where a user can check how the solar panels are doing at any given time. The end goal is to provide a fully functional prototype for the ECE department to use on one solar panel. With time and some refinement to the design, multiple interface boxes will be manufactured and installed on each of the ECEB research panels.


# Team Members

- Dillon Vadgama (dvadga2)
- Douglas Lee (dlee242)
- Sachin Reddy (ssreddy2)

BusPlan

Aashish Kapur, Connor Lake, Scott Liu

BusPlan

Featured Project

# People

Scott Liu - sliu125

Connor Lake - crlake2

Aashish Kapur - askapur2

# Problem

Buses are scheduled inefficiently. Traditionally buses are scheduled in 10-30 minute intervals with no regard the the actual load of people at any given stop at a given time. This results in some buses being packed, and others empty.

# Solution Overview

Introducing the _BusPlan_: A network of smart detectors that actively survey the amount of people waiting at a bus stop to determine the ideal amount of buses at any given time and location.

To technically achieve this, the device will use a wifi chip to listen for probe requests from nearby wifi-devices (we assume to be closely correlated with the number of people). It will use a radio chip to mesh network with other nearby devices at other bus stops. For power the device will use a solar cell and Li-Ion battery.

With the existing mesh network, we also are considering hosting wifi at each deployed location. This might include media, advertisements, localized wifi (restricted to bus stops), weather forecasts, and much more.

# Solution Components

## Wifi Chip

- esp8266 to wake periodically and listen for wifi probe requests.

## Radio chip

- NRF24L01 chip to connect to nearby devices and send/receive data.

## Microcontroller

- Microcontroller (Atmel atmega328) to control the RF chip and the wifi chip. It also manages the caching and sending of data. After further research we may not need this microcontroller. We will attempt to use just the ens86606 chip and if we cannot successfully use the SPI interface, we will use the atmega as a middleman.

## Power Subsystem

- Solar panel that will convert solar power to electrical power

- Power regulator chip in charge of taking the power from the solar panel and charging a small battery with it

- Small Li-Ion battery to act as a buffer for shady moments and rainy days

## Software and Server

- Backend api to receive and store data in mongodb or mysql database

- Data visualization frontend

- Machine learning predictions (using LSTM model)

# Criteria for Success

- Successfully collect an accurate measurement of number of people at bus stops

- Use data to determine optimized bus deployment schedules.

- Use data to provide useful visualizations.

# Ethics and Safety

It is important to take into consideration the privacy aspect of users when collecting unique device tokens. We will make sure to follow the existing ethics guidelines established by IEEE and ACM.

There are several potential issues that might arise under very specific conditions: High temperature and harsh environment factors may make the Li-Ion batteries explode. Rainy or moist environments may lead to short-circuiting of the device.

We plan to address all these issues upon our project proposal.

# Competitors

https://www.accuware.com/products/locate-wifi-devices/

Accuware currently has a device that helps locate wifi devices. However our devices will be tailored for bus stops and the data will be formatted in a the most productive ways from the perspective of bus companies.