Introduction
A solar charge controller is a regulator for your solar battery that prevents it from overcharging. Batteries are rated for voltage capacity, and exceeding that voltage can lead to permanent battery damage and loss of functionality over time. Solar charge controllers act as a gate to your battery storage system, making sure damage doesn’t occur from overloading it.With a PWM controller, your solar panel system and your home battery need to have matching voltages. In larger solar panel systems designed to power your whole home, panel and battery voltage aren’t typically the same. As a result, PWM controllers are more suited for small DIY solar systems with a couple of low voltage panels and a small battery.: In solar power system, charge controller is the heart of the system which was designed to protect the rechargeable battery.
The Advantages of Pwm arge controller include Higher Charging efficiency,longer battery life,Reduces battery overheating, Minimizes stress on the battery and Ability to desulfate it. This charge controller can be used for charging batteries, solar home system and also solar lantern in rural areas. Sadia Iftikhar and Fatima Zehra Alvi worked collectively to make this pwm charge controller.
Design Requirment
Our design requirment is that it should be as much compact as we can make it.Also, we must have main board and microcontroller board adjested on each other.
Sample Image of required Design
we are having this sketch of pwm charge controller in our mind.
Project Execution Plan
Week What we are goin to do in it
Week 1-2 Literature Review
week 3-4 Finding components
Week 5-6 Schematic Designig & Routing
week 7-9 PCB board Fabrication & Population
Week 10 Software Implementation
week 11-12 Testing And Troubleshooting
Week 13 Case Designing
week 14 Documentation
week 15 Finalizing
Task Distribution
Task Assigned Person
Literature Review Fatima
Components & its Info Sadia
schematic desiging & Routing schematic assigned to Fatima & Routing to sadia
PCB Population Collective Task
Software Implemention collective task
Testing And Troubleshooting Sadia
Case Designing Fatima
Documentation Fatima
High Level Design
This section should be just a high level diagram which explains the main components of your project and how they are integrated.Here you should layout the design specifications and components which you should choose as per requirements.
Description of Principle of Operations
1. The Micro-controller
The heart of the charge controller is Arduino nano board. The Arduino MCU senses the solar panel and battery voltages. According to these voltages, it decides how to charge the battery and control the load.Including PWM (pulse width modulation) is a tecnique by which we simply control a digital output signal by switching it on and off very quickly, by varying the width of the on/off duration, it will give the effect of varying the output voltage.
2. MOSFETs
In my charge controller I used a MOSFET, controlling the power flow from solar panel to battery .I used it for switching between solar panel and battery.
3. I/O Modules
Other Discrete Components
Component list
Here is the list of Components used in the project
Controller Board
- Arduino Nano (ATmega328P)
- Crystal Oscillator
- Capacitor (22px2,0.1,10ux2)
- push button
- AVR -SPI
- LEDs (RED & GREEN)
- Resistor (499×2,10)
- Header (6×01,7×01)
- FTDI
Main Board
- MOSFEts(IRF540)
- Diodes (IN$001×3,IN4007x2,Zener diode (IN5158))
- BJT (BCS547x5)
- Resistors (100×2,10×4,1Mx2,1K,220,680,820)
- Capacitors (47uF, 1uFx2)
- Connectors (6×1,7×1,2×1)
PCB schematic
Controller Board Schematic
Main Board Schematic
Troubles We Faced During Routing
Having schematic of controller board and main Board separately,when we started to route our boards, the first issue we faced was that how should we route two boards in a way that we can connenct them easily, so what we do was that we used two connectors to connect controller board with main board in a way that main board is palced on controller board.The next thing that troubled us was how route these two boards, so after routing and derouting the board around 4 to 5 times, we got a direction and started to route controller board by taking reference to Atmega238P and connectors in main board.when we have routed many of components, one more issue we faced was the components that were left could have a possible path to route them, so there we used resistors of 0 ohms to provide path to those components.
PCB layout
Controller Board Schematic
Main Board Schematic
Bill of Material
Fabricated PCB
This the picture of one of our fabricated board, as we have changed the boards 2 times so other picture is not available.
Populated Board
- Controller Board
This is our populated micro-controller board
- Main Board
Our Main board of the pwm charge controller is shown below
Procedure Adopted To Burn BOOTLOADER
We were using bootloader connector which was connected to PC through Usb port, Then we opened the Arduino program and write the bootlooder program there,which was then uploaded to the controller board
Challenges While Booting-up
Our Micro-controller was bootloaded in first attempt so we didn,t face any issue while booting up the micro-controller IC.
Successfull Built-up Circuit
Finally here is the output of our circuit
Flow code of Software Design
Reference of Project Implementation
Cost of Project
Component Cost
Atmega328P 299
Crystal Oscillator 10
capacitors 5xQuantity
Resistors 10/12
Diodes 6
BJTs 5
MOSEFTs 40
LEDs 5
LCD 700
That means it will cost around Rs.1300/-
Commercialization Aspects
The PWM Charge Controller can also be used as a BUSINESS MODEL as people in many far flung areas are still deprived of the basic need of electricity, so if this charge ontroller is used in these areas, it will help the people to at least use a bulb at night or also they can used it for charging purposes of phones etc.Also, It can also be sale to the companies who use batteries as there backup for electricty as this charge controller will help them to increase the life of battries. Also it is a cheap product that everyone can find it affordable as compared to other means of controllring battery systems.
Appendix
Report Submitted on Time …………………..
Matlab Profeciency …………………