Engineering Design Project: PWM Solar Charge Controller

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DESIGNING A PRODUCT THAT MEETS CUSTOMER’S
REQUIREMENTS
PWM SOLAR CHARGE CONTROLLER
Name
Date

TABLE OF CONTENTS
PWM Solar Charge Controller........................................................................................................1
Introduction......................................................................................................................................1
Plan, design solution and prepare a design specification in response to stakeholder’s design, brief
and requirements..............................................................................................................................1
Design conditions from customer................................................................................................1
Customer specification in style improvement.............................................................................1
Aimed Spicifications for Design.................................................................................................2
Strategy process...........................................................................................................................2
Block Diagram.........................................................................................................................2
Project process planning..........................................................................................................2
Assessment of PWM charger...................................................................................................3
Formulate possible practical results to address the student prepared design specification.............4
Methodology................................................................................................................................4
Practical design-using Nano........................................................................................................5
Practical Design-using PIC..........................................................................................................5
Assessment of practical designs..................................................................................................6
Assortment of concluding design................................................................................................6
Gears used for prototyping..........................................................................................................6
Enhancement for design..............................................................................................................7
Prepare an industry standard engineering methodological design report........................................7
Practical design............................................................................................................................7
Concluding design drawback.......................................................................................................7
Part of specification in ended product.........................................................................................8

Protection and hazard administration problems..........................................................................8
Efficacy of design........................................................................................................................8
Scheme to present report.............................................................................................................9
Effectiveness of presentation strategy.......................................................................................10
Response of customer................................................................................................................10
Enhancement recommendation..................................................................................................11
Conclusion.................................................................................................................................11
Appx 1 Representation of primary design.................................................................................11
Appx 2 Final design of PWM solar Charge Regulator..............................................................11
Appx 3 Code of PWM solar Charge Regulator.........................................................................12
Figure 1 Weightage graph of customer's requirement and anticipated restriction for design
selection...........................................................................................................................................5
Figure 2Block diagram of PWM regulator......................................................................................6
Figure 3strategy plan.......................................................................................................................6
Figure 4 gantt chart PWM regulator................................................................................................7
Figure 5PWM vs MPPT..................................................................................................................7
Figure 6graphical differences between PWM and MPPT...............................................................7
Figure 7voltage sensor.....................................................................................................................8
Figure 8current sensor.....................................................................................................................9
Figure 9schematic design..............................................................................................................10
Figure 10Circuit diagram of PWM charge controller using PIC MICROCONTROLLER..........10
Figure 11design specifications using Arduino vs using PIC.........................................................11
Figure 12Components used in Model............................................................................................12
Figure 13Contribution design measurement in ended product......................................................13
Figure 14Led status........................................................................................................................14
Figure 15performance approach....................................................................................................15
Table 1Feedback Questions...........................................................................................................12

PWM SOLAR CHARGE CONTROLLER
INTRODUCTION
A charge regulator or controller is essentially a voltage and current regulator to stay batteries
from overcharging. It regulates the voltage as well as current returning from the panels reaching
to the battery. Most "12 volt" panels place out regarding sixteen to twenty volts, thus if there's no
regulation the batteries are going to be spoiled from overcharging. Most batteries would like
around fourteen to fourteen volts to urge absolutely charged.
A charge controller, battery regulator or charge regulator limits the speed at that current is
superimposed to or drawn from electrical batteries It prevents overcharging and will shield
against over voltage, which might cut back battery performance or time period, and will cause a
security risk. It’s going to additionally stop utterly debilitating "deep discharging" battery, or
perform controlled discharges, betting on the battery technology, to guard battery life.
Power electronics circuit is castoff in a PV charge controller to get maximum efficiency,
obtainability and reliability. Use of power electronics circuits such as numerous dc to dc
converters like buck, boost, buck-boost converter and others converter as power conditioning
circuitry to offer a desired current to charge battery successfully.
PLAN, DESIGN SOLUTION AND PREPARE A DESIGN
SPECIFICATION IN RESPONSE TO STAKEHOLDER’S DESIGN,
BRIEF AND REQUIREMENTS.
DESIGN CONDITIONS FROM CUSTOMER
We are assigned with project of coming up with a simple solar charge controller for consumer.
Consumer needs a fairly correct and simple to use controller. Design based on discrete
components like transistors, using specialized IC’s /Microcontrollers. If micro-controller
development board is opt for planning solar controller then Arduino development board is
desirable for design.

CUSTOMER SPECIFICATION IN STYLE IMPROVEMENT
We tend to try and establish the necessary specifications of a PWM Charge Controller In
addition, we tend to study a solar charger operating as relation to perceive the operating of
Figure 1 Weightage graph of customer's requirement and anticipated restriction for design selection
PWM solar Charge Controller. The reference study facilitate us in identification of necessary
elements of a PWM star Charge Controller. The foremost part of charge controller are Fuse
Holder and fuses, 20x4 I2C LCD, .P-MOSFET and Arduino Nano.
Now, we tend to assign these parts importance weightage consistent with project and to
parameters which can be used for analysis of style resolution. We tend to assign weightage on
the scale of one to ten as shown in Figure 1, wherever one being lowest while ten being highest
importance. The figure one illustrate appointed importance weightage to completely different
parts and analysis parameters.
AIMED SPICIFICATIONS FOR DESIGN
We come across with consumer for discussion related to style specifications from style brief. We
tend to additionally recommend some alternatives for style specifications. After meeting, we tend
have some demand for project.
Fuse Holder and fuses
20x4 I2C LCD
Buck Converter
Arduino Nano

Arduino Nano
Arduino Nano, a minor, well-suited, flexible and breadboard approachable Microcontroller,
established by Arduino.cc at Italy,
It arises with an voltage of 5 Volts, but the input voltage can differ from 7 volts to 12 Volts.
Arduino Nano Pinout comprises 14 digital, 8 analog, 2 Reset and 6 Power Pins.
Individual of these Digital and Analog Pins remain assigned with numerous functions but their
key function is to be organized as input or an output.
They are represented as input pins once they are interfaced with devices, but if you are driving
load then used as output. pinMode() and digitalWrite() are used to regulate the operations of
digital pins although analogRead() is used to controll analog pins.
Analog pins come up with a entire resolution of 10 bits which calculate the value from 0 to 5
Volts. Arduino Nano arises with a crystal oscillator of16 MHz. and is used to produce clock of
exact frequency using fixed voltage.
Heat Sink
Heat sink is passive temperature exchanger. It removes the heat generated by an electric or
mechanical means to fluid medium, frequently air or liquid coolant, where it is removed away
from the device, so permitting parameter of the device's temperature at ideal levels. High power
semiconductors such as a power transistor and optoelectronics such as a lasers and light emitting
diodes LED heat sinks are used, the heat dissipation skill of the component himself is inadequate
to lower its temperature.
LCD_2x16
A 16x2-LCD display is basic module and it is very frequently used in numerous devices and
circuits. These components are chosen over seven segments and supplementary multi segment
LEDs. The explanations being: LCDs are cheap; simply programmable; have no restraint of
displaying distinct & even custom fonts or animation.
16x2-LCD means it can display 16 letters per line and there are two such positions. In this LCD
individual character is displayed in 5x7 pixel matrix. This LCD has only 2 registers that are
Command and Data.

MOSFET
The MOSFET transistor, a semiconductor, is extensively used for interchanging and magnifying
electric signals in the electronic devices. The MOSFET is a center of integrated circuit and as of
these very small dimensions, MOSFET can be intended and fabricated in a solitary chip. The
MOSFET is a 4 terminal device and those are source, gate, drain and body pins. The body of the
MOSFET is often connected to the source terminal creating it a three terminal device like field
effect transistor. The MOSFET is far the most common transistor and it is used in both analog
and digital devices.
STRATEGY PROCESS
Block Diagram
Figure 2Block diagram of PWM regulator
PROJECT PROCESS PLANNING
Our initial task in design process is to fulfill with customer to induce understanding of desired
product. Demand are gathered regarding product, discuss implications of necessities. Once
necessities absolutely understood then the method of developing completely different design
ideas are going to be started. These design ideas are evaluated on basis of bound parameters to
pick out a final design. Once final design chosen, its example modeling crop up. Then
developing model testing can be performed keeping seeable its applications. Recommended
improvements are implemented on the idea of feedback and this method can continues to test
style till it satisfy desired demand. Once demand are satisfied, a final meeting with customer is
conducted. During this meeting we have a tendency to gift final product and elaborate its design
operation.

Figure 3strategy plan
Figure 4 gantt chart PWM regulator
ASSESSMENT OF PWM CHARGER
Comparison between PWM solar charger vs MPPT solar charger
Figure 5PWM vs MPPT

Graphical differences between PWM and MPPT
Figure 6graphical differences between PWM and MPPT
FORMULATE POSSIBLE PRACTICAL RESULTS TO ADDRESS
THE STUDENT PREPARED DESIGN SPECIFICATION.
METHODOLOGY
Purpose solar charge controller is to shield the rechargeable battery. To design this charge
controller, it consists of 7 components wherever the primary part
Will be buck convertor circuit,
2nd, a small controller circuit,
3rd, a driver circuit,
Figure 7voltage sensor

4th, rechargeable battery
5th voltage sensing element,
Figure 8current sensor
6th is current sensing element
7th is liquid display, LCD
PRACTICAL DESIGN-USING NANO
The CPU of the charge controller is Arduino Nano. The Arduino Microcontroller intelligences
the solar battery and battery voltages. According to this powers it decides a way to charge the
battery as well as manage the load.
The quantity of charging current is definite by distinction between battery voltage and charge
plug voltages. The controller uses 2 steps charging rule. According to the charging rule it offers a
set frequency PWM signal to battery featuring p-MOSFET.

Figure 9schematic design
The frequency of PWM signal is 490Hz. Duty cycle 0 to100% is in sync by the error signal. The
controller delivers HIGH / LOW command to the load phase p-MOSFET in keeping with the
dusk/dawn also battery voltage.
PRACTICAL DESIGN-USING PIC
Power obtained from the solar panel can return to the comparator using potential divider rule.
Comparator are going to be linked to the microcontroller that will be additionally an ADC pin.
Figure 10Circuit diagram of PWM charge controller using PIC MICROCONTROLLER
We have a tendency to be using comparator to notice day or dark. If the battery voltage is over
6v then it'll be believed as day time, otherwise microcontroller can contemplate as night. Load
driver can confirm whether or not the load is on or off.

If battery voltage is a smaller amount than ten volt then loads are going to be disconnected
mechanically. Battery is taken into account as input and load is taken into account as output of a
load driver. Load driver is connected with of microcontroller. Charging current is measured by
employing a PWM driver. We’ll contemplate the solar plate’s voltage as the input and battery as
an output. PWM is coupled with microcontroller.
ASSESSMENT OF PRACTICAL DESIGNS
In this section, analysis of technical styles meted out victimization sure parameters. This analysis
activity helps in choosing final style for project. On the premise of analysis we'll select a final
technical style.
Figure 11design specifications using Arduino vs using PIC
All parameters are rated on scale of one – ten, one being least and ten being best. Every analysis
perform by keeping in mind technical styles and client’s necessities.
ASSORTMENT OF CONCLUDING DESIGN
We in brief discuss every design, resolution with its faults. Then assess them on the idea of
bound parameters. After calculations we discover out that design first using Arduino dominate
alternative style thus we decide design using Arduino as final style for PWM charge regulator.
GEARS USED FOR PROTOTYPING
Followings are the gears used for software designing and scheming circuit diagrams.