THE KIAMBU NATIONAL POLYTECHNIC

DIPLOMA IN ELECTRIC AND ELECTRONICS

ENGINEERING (POWER OPTION)

TRADE PROJECT
TITTLE: WIRELESS MOBILE CHARGER
PRESENTED BY: JOHN KARIUKI MUCHIRI
INDEX NUMBER:2051013119
PRESENTED TO: THE KENYA NATIONAL
EXAMINATION COUNCIL FOR THE AWARD OF A
DIPLOMA IN ELECTRICAL AND ELECTRONICS
ENGINEERING (POWER OPTION)
SUPERVISOR: RICHARD KARIMI
EXAMINATION SERIES: JULY SERIES 2024

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DECLARATION
I present this project as my original work , and confirm that it has not been presented any where for
the award of academic achievement in any other institution of learning.

Signature ………………………………………………… Date…………………………………………

Name ……………………………………………………………………..

This project has been submitted for the examination with my approval as the supervisor

Signature…………………………………………………… Date

Name………………………………………………………………………..

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DEDICATION
I dedicated these project to the lovely and caring family have been with me in
all aspects of life and also showing me ways of God, friends, teachers who have
taught me up to this level and all people who offered assistance to my project.
May God continue showering them with more blessings, love and caring heart.

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ABSTRACT
With the proliferation of mobile devices in our daily activities, the demand for
convenient and efficient charging solutions has never been higher. The project
illustrates the of invention a wireless charger designed to address the
limitations of traditional wired chargers. Utilizing advanced electromagnetic
induction technology, the charger provides seamless power delivery to mobile
devices without the hassle of cables. The system comprises of a transmitter
unit and a receiver unit, enabling users to charge their devices at a go, free
from constraints of a traditional power cable. More over the charger
incorporates intelligent power management features to optimize charging
efficiency and ensures compatibility with a wide range of devices.

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 CHAPTER ONE
BACKGROUND OF THE STUDY
Introduction:
Wireless charging technology has emerged as a convenient and efficient
method for powering mobile devices without the need of cables.With
the widespread adoption of smartphones, tablets and other portable
electronics, the demand for wireless charging solutions has increased
significantly. This background study aims to explore the current state of
wireless charging technology, identify key challenges, and establish the
rationale for the proposed mobile charger project.

Overview of wireless charging technology

Wireless charging, utilizes electromagnetic fields to transfer energy from
a charging pad to a compatible device without the need of physical
connectors. The technology relies on coils in both the charger and the
device to create a magnetic field, which induces an electric current to
charge the device’s battery.

Current market landscape

The market for wireless chargers has experienced rapid growth in recent
years, driven by increasing consumer demand for convenience and
proliferation of Qi-enabled devices. Additionally, the automotive
industry has begun incorporating wireless charging pads into vehicles,
providing users with seamless charging while on the go.

statement of problem
In the realm of modern mobile technology, the reliance on traditional
wired charging methods poses significant limitations in terms of
convenience, portability, and user experience. Despite advancements in
wireless technology, there exist several challenges hindering its
widespread adoption and optimal functionality. Therefore, the primary
problem addressed by this research project is to identify analyze, and
mitigate the technical, user-centric, regulatory and environmental
barriers associated with the implementation and usage of wireless
mobile chargers.

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1.1 Research Questions
• What are the optimum design parameters for maximizing charging
efficiency while ensuring compatibility and safety?
• How does the convenience of wireless charging impact user behavior
and device usage patterns?
• What safety considerations and regulatory requirement exist for
wireless charging technology, particularly concerning electromagnetic
interference and device safety?
• What is the environmental footprints of wireless charging technology
compared to traditional wired charging methods?
• What emerging technologies and advancements are likely to shape the
future of wireless charging for mobile devices?

MAIN OBJECTIVE

• The main objective of these project is to is to design and

develop a portable charging solution that enables users to
conveniently charge their mobile devices without the need for
physical cable connections

SPECIFIC OBJECTIVE

• To develop and durable and reliable charging system – Engineering the

charger to withstand everyday wear and tear, ensuring long-term
durability and reliable performance under various environmental
conditions.
• To construct a user-friendly design- creating a user-friendly interface
that allows for easy placement and charging of mobile devices without
the need for precise alignment.
• To construct a portable design charger that in lightweight
• To develop an efficient power transfer mechanism to maximize charging
speed and minimize energy loss.

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• To develop safety features to protect the charger and mobile device
from overheating, overcharging and short circuits.
• To develop performance features with cost effectiveness to make the
wireless charger accessible to a wide range of consumers.

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1.2 Significance of study

The significance of studying wireless mobile charger projects lies in their

potential to address several key issues and contribute to advancements in
technology and user experience. Some significances include:

• Convenience and accessibility: wireless mobile chargers offer a more

convenient and accessible way to charge devices compared to
traditional wired chargers.
• User experience Enhancement: these will be enhance by improving
charging speed, efficiency and reliability, ultimately leading to greater
use satisfaction with their devices.
• Technological innovation: Researching wireless mobile chargers allows
one to me explore new technologies, materials, and design concepts
that can advance the field and drive technological innovation.
• Environmental impact reduction: wireless charging has the potential to
reduce electronic waste by eliminating the need for disposable charging
cables, and hence reducing the carbon footprint associated with the
electronic devices.
• Cross-Industry Applications: The significance of wireless mobile charger
studies extends beyond consumer electronics to other industries such as
automotive, healthcare, and smart home devices. Understanding
wireless charging technology opens up opportunities for its application
in various sectors, leading to interdisciplinary collaborations and
innovations.
• Consumer Empowerment: By studying wireless mobile chargers,
consumers gain a better understanding of the technology, its benefits,
and its limitations.

1.5Organisation of the study

Organizing the study of a wireless charger project involves breaking down the
research and development process into manageable components.

1.5.0Introdution

In an era marked by the relentless pursuit of convenience and efficiency, the

evolution of charging technology stands as a pivotal frontier in the realm of
consumer electronics. Among the myriad innovations in this domain, wireless
charging emerges as a transformative force, promising to liberate users from
the constraints of traditional wired connections. This study embarks on a

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journey into the heart of wireless charging technology, aiming to unravel its
mysteries, explore its potentials, and contribute to its ongoing evolution.

1.5.1Background and Context

The proliferation of smartphones, wearables, and other portable electronic

devices has fueled the demand for charging solutions that seamlessly integrate
into modern lifestyles. Conventional wired chargers, while effective, pose
limitations in terms of portability, durability, and user experience. As such, the
quest for a more elegant and user-friendly charging method has driven the
exploration of wireless charging technology.

1.5.2Block diagram

DC POWER
SOURCE

OSCILLATOR Transmitter AC Receiver R

DC
Rectifier
coil (Tx)
X

Voltage
1.5.3Block diagram description Load
regulator
In this project, the wireless charger works mainly works on the principle of
inductive coupling.
From the Block diagram, it is clear that for the overall functioning of wireless
charger circuit, it required a wireless power transmitter and a wireless power
receiver section.
The transmitter coil in this wireless power transmitter section converts the DC
power from oscillator to ahigh frequency AC power signal. This high frequency
alternating current, which is linked with the wireless power transmitting coil,
would create an alternating magnetic field in the coil due to induction, to
transmit energy.

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In the wireless receiver section, the receiver coils receive that energy as an
induced alternating voltage (due to induction) in its coil and a rectifier in the
wireless power receiver section converts that AC voltage to DC voltage.
Finally this rectified DC voltage would be feed to the load through the voltage
regulator section. That is, the wireless power receiver section main function is
to charge a low power battery through inductive coupling.

CHAPTER TWO
Literature review
2.0Introduction

Certainly! The literature review for a wireless mobile charger project would
begin by examining existing research, technologies, and advancements related
to wireless charging, particularly in the context of mobile devices. Here's how
you might structure the introduction to your literature review:

Wireless charging technology has garnered significant attention in recent years

as a convenient and efficient method for powering electronic devices,
particularly mobile phones. As the demand for mobile devices continues to
rise, there is a growing need for innovative charging solutions that offer
increased convenience, flexibility, and user-friendliness. In this literature
review, we explore the current state of wireless charging technologies, with a
focus on their application in mobile device charging systems.

Importance of wireless charging

Traditional wired charging methods, while effective, come with certain
limitations such as the need for physical connectors, susceptibility to wear and
tear, and restrictions on mobility. Wireless charging presents a promising
alternative by eliminating the need for cables and connectors, allowing for
seamless charging experiences in various environments. Moreover, wireless
charging technology has the potential to enhance user convenience,
streamline device integration, and contribute to the development of next-
generation mobile ecosystems.

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Objectives

The primary objectives of this literature review are as follows:

1. To provide a comprehensive overview of existing wireless

charging technologies in the context of mobile devices.
2. To identify key challenges and limitations associated with
current wireless charging systems.
3. To highlight recent advancements and innovations in the field,
along with their potential implications for future research and
development.
4. To offer insights and recommendations for the design and
implementation of wireless mobile charging solutions that
address the needs of diverse user scenario

2.1Theoretical framework

The theoretical framework of a wireless mobile charger project serves as the

conceptual foundation that guides the design, development, and
implementation of the project. It typically encompasses theories, principles,
and models relevant to wireless power transfer, mobile device charging, and
related areas. The theoretical frame work include:

1. Electromagnetic induction
Electromagnetic induction forms the basis of wireless power transfer
technology. According to Faraday’s law of electromagnetic induction, a
charging magnetic field induces an electromotive force in a conductor,
leading to the generation of electric current. In the context of wireless
charging electromagnetic induction is utilized to transfer power
wirelessly from a transmitter(charger) to a receiver (mobile device)
through coupled magnetic fields.

2. Resonant Inductive Coupling

Resonant inductive coupling (RIC) is a method employed in wireless
charging systems to enhance power transfer efficiency and extend the
operating range. By tuning the frequencies of transmitter and receiver
coils to resonate with each other, RIC enables efficient energy transfer
over longer distances. This principle is crucial for optimizing the
performance of wireless mobile chargers, particularly in scenarios where
precise alignment between the charger and the device may not be
feasible.

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3. Circuit Model of Inductive Power Transfer Systems
The circuit model of inductive power transfer (IPT) systems provides a
theoretical framework for analyzing the electrical characteristics and
performance parameters of wireless chargers. This model typically
includes components such as the transmitter coil, receiver coil, coupling
coefficient, load impedance, and resonant capacitor. Understanding the
interactions between these components is essential for optimizing
system efficiency, power transfer capability, and electromagnetic
compatibility (EMC) considerations.

4. Power electronics and control strategies

Power electronics play a crucial role in the design and operation of
wireless mobile chargers. Various control strategies, such as pulse-width
modulation (PWM), phase-shift modulation, and feedback control, are
employed to regulate the power transfer process, maintain optimal
operating conditions, and ensure compatibility with different mobile
device specifications. Theoretical models and control algorithms are
essential for implementing efficient and reliable charging solutions.

5. Human Factors and User Experience

Consideration of human factors and user experience principles is integral
to the design of wireless mobile chargers that meet the needs and
preferences of end-users. Theoretical frameworks related to user
interface design, ergonomics, usability testing, and user-centered design
methodologies contribute to the development of charging solutions that
offer intuitive operation, convenience, and satisfaction.
6. Efficiency Optimization Models
Efficiency optimization models focus on maximizing the power transfer
efficiency of wireless charging systems while minimizing losses.
Theoretical frameworks such as maximum power transfer theorem,
impedance matching theory, and optimization algorithms are utilized to
analyze system parameters, coil geometries, and operating conditions to
achieve optimal efficiency levels.
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7. Electromagnetic field analysis
Electromagnetic field analysis involves theoretical modelling and
simulation techniques to study the distribution and behavior of magnetic
fields in wireless charging systems. Finite element analysis (FEA),
method of moments (MoM), and finite difference time domain (FDTD)
methods are commonly used to predict electromagnetic phenomena,
such as magnetic flux density, eddy currents, and electromagnetic
interference (EMI), aiding in the design and optimization of charger and
receiver coil geometries.

8. Standards and Regulatory Frameworks

Standards and regulatory frameworks provide guidelines and
specifications for the design, testing, and certification of wireless
charging systems. Theoretical frameworks related to international
standards organizations (e.g., International Electrotechnical Commission
- IEC, Institute of Electrical and Electronics Engineers - IEEE) and
regulatory bodies.

9. Environmental Impact Assessment

Environmental impact assessment frameworks evaluate the ecological
footprint and sustainability implications of wireless charging technologies.
Theoretical models, such as life cycle assessment (LCA) and carbon
footprint analysis, are employed to quantify energy consumption,
greenhouse gas emissions, and resource utilization associated with the
production, use, and disposal of wireless chargers and mobile devices,
guiding efforts to minimize environmental impact.

10. Economic Analysis and Cost-Benefit Models

: Economic analysis frameworks assess the cost-effectiveness and financial
viability of deploying wireless charging solutions in various contexts.
Theoretical models, such as cost-benefit analysis, return on investment
(ROI), and total cost of ownership (TCO), evaluate factors such as initial
investment costs, operational expenses, energy savings, and potential
revenue streams, aiding decision-making processes and investment
prioritization.

11. Maxwell's Equations: maxwell’sequations describe the behavior of

electric and magnetic fields and their interactions in space and time. They
form the basis of electromagnetism and are fundamental to
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 understanding how electromagnetic waves propagate and interact with
objects, including inductive charging coils. Maxwell's equations help in
analyzing the electromagnetic fields generated by wireless chargers,
understanding the principles of electromagnetic induction, and predicting
the efficiency and range of wireless charging systems.

12. Heat transfer

Heat transfer principles are essential for understanding the thermal
behavior of components within a wireless charging system. As energy is
transferred wirelessly from the charger to the device, components such as
coils, circuitry, and batteries may generate heat due to resistive losses or
inefficient energy conversion. Heat transfer theory helps in analyzing
thermal management strategies, designing cooling mechanisms, and
ensuring that the system operates within safe temperature limits to
prevent overheating and thermal damage.
a. Conduction
Conduction is the transfer of heat through a material or between
materials that are in direct contact with each other. In a wireless
mobile charger, conduction may occur within the components of
the charging system, such as the charging coils, circuitry, and
housing. Heat generated during the wireless charging process can
conduct through these materials, potentially leading to
temperature increases in the charger and the mobile device.

b. Convection
Convection is the transfer of heat through a fluid (liquid or gas)
due to the movement of the fluid itself. In the context of a
wireless mobile charger, convection may occur if the charging
system or the mobile device generates sufficient heat to cause air
movement around them. Natural convection, driven by buoyancy
forces, or forced convection, aided by external fans or cooling
mechanisms, may help dissipate heat and prevent overheating of
the components.

c. Radiation
Radiation is the transfer of heat through electromagnetic waves,
without the need for a medium. While radiation is generally less
significant in closed environments with opaque materials (such as
within the charger or the mobile device), it can still play a role in
heat transfer between surfaces with different temperatures. For

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 instance, components with high temperatures may radiate heat to
their surroundings or to adjacent components.

13 Circuit theory

Circuit theory provides the foundation for analyzing the electrical behavior of
wireless charging systems. Concepts such as Ohm's law, Kirchhoff's laws, and
impedance matching are applied to model the electrical circuits comprising
transmitter and receiver coils, power electronic converters, and control
systems. Circuit theory helps in optimizing circuit designs, calculating voltage
and current distributions, and predicting the electrical performance of the
charging system under various operating conditions.

2.2Review of previous studies

In a review of the previous studies I will delve in to existing research,

developments, and findings in the field of wireless charging
technology.

a) Inductive coupling for power transfer

Many studies have focused on inductive coupling as the
primary method for wireless power transfer. This
approach can achieve efficient power transfer over short
distances.
b) Resonant Inductive coupling
This method is a promising technique for improving the
efficiency and range of wireless charging systems. Studies
have shown that resonant circuits can be tuned to match
the resonant frequency of the coils resulting in enhanced
power transfer efficiency and longer charging distances.

c) Coil design and placement

Studies have investigated the impact of coil design and
placement on the performance of wireless charging
systems. Optimal coil geometrics, including size, shape
and number of turns have been explored to maximize
power transfer efficiency.

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 d) Safety considerations
Safety is a critical aspect and various considerations have
been addressed such as evaluating electromagnetic field
exposures levels ensuring compliance with regulatory
standards and implementing measures to prevent
overheating and overcharging.

e) Integration with consumer electronics

Research have explored the design of compact and light
weight charging modules that can be seamlessly
integrated into portable devices without comprising
performance or user experience.

f) User acceptance and adoption

Understanding user perceptions and behaviors towards
wireless technology has been the focus of several studies.
With the charging speed, convenience and compatibility
with existing devices, it insights valuable for designing
wireless chargers that meet the needs and preference of
end-users.

2.3 Synthesis and critique

A wireless mobile charger project typically involves designing a system that can
charge a mobile device without the need for physical connections, using
technologies like electromagnetic induction or resonance.

2.3.1 synthesis

The hardware components required to design the proposed project on

wireless mobile charger are:

1. Copper wire (25 gauge)

A copper wire is a single electrical conductor made of copper. Copper has the
lowest resistance to the flow of electricity of all non precious metals.

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2.IRFZ44N MOSFET
MOSFET is an abbreviation for metal-oxide semiconductor field-effect
transistor. They have a Gate, source and a drain. Unlike transistors, MOSFETs
are voltage controlled devices i.e. they can be turned on or off by supplying the
required Gate threshed voltage.

3. 9 volt battery
A battery is a source of electric power consisting of one or more
electrochemical cells with external connections for powering electrical devices.
When a battery is supplying power, its positive terminal is the cathode and its
negative terminal is the anode .

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 4.ic4007 diode
A diode is a device which allows current flow through only one direction. That
is the current should always flow from the anode to the cathode.

5, 100microfarads capacitor
Capacitors are electrical componets that store electric charges.

5. LM7805
The 7805 voltage regulator IC is a commonly used voltage regulator that finds
its application in most of electronic devices. It provides a constant +5V output
voltage for a variable input voltage supply.

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 7.Resistors
A resistor is a passive electronic component and senses to prevent or limit the
flow of electrons. It is a two terminal device that works on the principle of
ohm’s law which prevent 0verflow of voltage

8.LED (light emitting diode)

Led is a pn junction diode which emits light when forward biased. It has two
legs the longer one being the anode and shorter one being the cathode.

9.switch
It is an electrical component that can disconnect or connect the conducting
path in an electrical circuit, interrupting the electric current or diverting it from
one conductor to another.

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10. Breadboard
A bread board is a construction base for prototyping of electrons,

CHAPTER THREE
RESEARCH METHODOLOGY
3.0. Introduction
Wireless charging technology enables wireless power transfer from a power
source such as charger to a load such as a mobile device conveniently across in
air gap by eliminating the bunch of wire. Wireless power transmission involves
the exchange of power without the need for physical connections.
3.1 Research design
• The research design of the project adopts a multifaced approach,
encompassing both theoretical investigation and practical
experimentation.
• Literature review- the project begins with an extensive review of
existing literature aiming to understand the fundamental principles
recent advancements and challenges in wireless charging technology.
This phase provides a solid theoretical foundation for all the stages

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• Conceptualization and design- here I came up with ideas evaluating
them and outling the conceptual framework for the project. This
includes considerations such as charging efficiency, compatibility with
various devices and user experience.

• A transmitter circuit and a receiver circuit are the main circuits in the
project. The transmitter circuit consists of an Z44 MOSFET which
converts the DC power supply to AC. Then, with the help of the
transmitting coil the wireless power gets transmitted to the receiver
circuit. The receiver circuit receives the power through the receiving coil
and passes through the rectifier circuit (consisting od diode and
capacitor). The AC received by the receiver coil is converted into DC
current with the help of bridge rectifier. After that a 100 micro farad
capacitor is used to filter the ripples and pure DC is supplied. The pure
DC is then passed through the voltage regulator to get a regulated 5V DC
and it is then given to the cable from which the mobile charging is
achieved.

• Prototyping and testing-With the conceptual framework in place the

project proceeds to the prototyping and testing phase. Utilizing available
resources protypes of the wireless mobile charger are developed and
subjected to rigorous testing. This involves evaluating charging efficiency
safety, reliability and user -friendliness under various conditions.

• Optimization and iteration – feedback from testing informs iterative

optimization of the wireless mobile charger design. This iterative process
involves refining the prototype based on identified short comings and
opportunities of improvement.The goal is to enhance performance,
address the technical challenges and ensure compatibility with different
devices.

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 • Evaluation and validation – The aim is to validate the effectiveness
and practicality of the wireless charger in meeting user needs and
expectations.

3.2 Data collection methods

In a research project focused on wireless mobile chargers, several methods of

data collection can be employed to gather relevant information and insights.
Some of the methods used are:
✓ Surveys-Administering surveys to users, manufacturers, or experts to
gather opinions, preferences, and feedback on wireless charging
technology.
✓ Interviews- conducting interviews with users to gain in-depth insights in
to their perspective challenges and suggestions on the cabled charger
and on the wireless charger.
✓ Observational studies-observing how users interact with chargers in
various environments to understand the usage patterns common
behaviors and potential obstacles.
✓ Field trials- Conducting field trials or pilot studies to evaluate the
performance of wireless charging systems in real-world conditions over
an extended period.
3.3 data analysis procedures
Data analysis procedures involve processing and interpreting collected data to
draw meaningful conclusions and insights. Here are some common data
analysis procedures:

1. Data Cleaning:

• Remove any outliers or errors in the collected data that could skew the
analysis.
• Check for missing or incomplete data and decide on appropriate
handling methods, such as imputation or exclusion.

2. Descriptive Statistics:

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 • Calculate summary statistics such as mean, median, mode, standard
deviation, and range to describe the central tendency, dispersion, and
distribution of the data.
• Use histograms, box plots, or frequency tables to visualize the
distribution of key variables.
• CIRCUIT DIAGRAM

The circuit for wireless power transfer consist of a 9V battery rectifier, lc

oscillator, transmitter, receiver and current amplifier, voltage regulator

Current amplifier

Here we use MOSFETs Z44 to invert the DC current to AC. It also works as a
current amplifier that is it increases the efficiency of the coil

Transmitter coil

Power supply is given to the transmitter. Copper coil is wound into several
turns. When power supply is given to the coil, a magnetic field is produced.
Hence the power gets transferred.

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Receiver coil

The receiver coil is the secondary coil and has the same design as the primary
coil. Running the secondary at the same resonant frequency as the primary
ensures that the secondary has low impedance at the transmitters frequency
and that the energy is optimally absorbed. To remove energy from the
secondary coil, different methods can be used, the AC can be directly rectified
and a regulator circuit can be used to generate DC voltage.

Rectifier

The output from the secondary coil is rectified by the use of a rectifier using
four diodes connected with each other. The rectifier is used to convert AC to
DC. The full wave rectifier produces a smooth DC with no ripples. I n the
positive half of the AC cycle, D1 &D2 conduct because there are forward
biased. Positive voltage is on the anode of D1 and negative voltage is on thr
cathode of D2. Thus, these two diodes work together to pass the first half of
the signal through. In the negative half of the AC cycle, D3 and D4 conduct
because they are forward biased: Positive voltage is on the anode of D3 and
negative voltage is on the cathode of D4.The net effect of the bridge rectifier is
that both halves of the AC sine wave are allowed to pass through but the
negative half of the wave is inverted so that it becomes positive to produce
pure DC .

LC oscillator circuit

The electric current and the charge on the capacitor is the circuit undergoing
electrical LC oscillations when a charged capacitor is connected to an inductor.
The LC circuit is used to select or generate a specific frequency signal. The

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process continues at a definite frequency and if no resistance is present in the
LC circuit, then the LC oscillations will continue indefinitely.

Voltage regulator

Voltage regulator is used to obtain a constant DC source. We use IC 7805 for

this purpose. The number 78 signifies that it is a positive voltage

3. Qualitative Analysis:

• If qualitative data, such as interview transcripts or open-ended survey

responses, are collected, use qualitative analysis techniques such as
thematic analysis or content analysis to identify recurring themes or
patterns.

4. Interpretation and Reporting:

• Interpret the results of the data analysis in the context of the research
objectives and hypotheses.
• Discuss the implications of the findings and their relevance to theory,
practice, or future research.
• Present the results in a clear and concise manner, using tables, figures,
and written explanations.

5. Inferential Statistics:

• Conduct hypothesis tests, such as t-tests or ANOVA, to compare means

or proportions between different groups or conditions.
• Perform correlation analysis to explore relationships between variables,
such as the relationship between charging efficiency and distance
between the charger and the device.

6. Regression Analysis:

• Use regression models to analyze the relationship between predictor

variables (e.g., coil alignment, power output) and the outcome variable
(e.g., charging efficiency).
• Conduct regression diagnostics to assess the goodness-of-fit and identify
any violations of assumptions.

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7. Time Series Analysis:

• If the data are collected over time, conduct time series analysis to
identify patterns, trends, and seasonal effects.
• Use techniques such as moving averages, exponential smoothing, or
ARIMA models to forecast future trends in wireless charging
performance.

8. Factor Analysis:

• Employ factor analysis to identify underlying factors or latent variables

that explain the variability in the data.
• Explore whether certain characteristics or features of wireless chargers
are related to overall performance.

3.4 Validity and reliability

Validity refers to the extent to which a research study or experiment

measures what it is intended to measure, and the results accurately
reflect the phenomenon under investigation.

CHAPTER FOUR
4.1DATA ANALYSIS

1. Charging Efficiency Analysis

Methodology:

✓ Collected data on charging times and battery levels for various devices
using the wireless mobile charger.
✓ Calculated the charging efficiency by comparing the time taken to charge
the device wirelessly with the time taken to charge using a conventional
wired charger.

results:

✓ The charging efficiency of the wireless mobile charger was found to be

68% on average.

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 ✓ Variability in charging efficiency was observed across different device
models and battery capacities.

Interpretation:

✓ The charging efficiency indicates the effectiveness of the wireless

charging technology.
✓ Factors such as device compatibility, charging distance, and battery
health may influence charging efficiency.

2.Charging Distance Analysis

Methodology:

✓ Conducted experiments to measure the maximum charging distance at

which the wireless mobile charger could effectively charge a device.
✓ Recorded charging success rates at various distances from the charger.

Results:

✓ The maximum charging distance observed was 60 cm, beyond which

charging was inconsistent or not possible.
✓ Charging success rates decreased as the distance between the device
and the charger increased.

Interpretation:

✓ The charging distance is a critical factor in determining the practicality

and convenience of wireless charging.
✓ Understanding the limitations of charging distance helps users optimize
the placement of their devices for efficient charging.

3. Heat Generation Analysis

Methodology:

✓ Monitored the temperature changes of devices and the wireless charger

during charging sessions.

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 ✓ Recorded the maximum temperature reached by each device and the
charger.

Results:

✓ The wireless charger and devices experienced temperature increases

during charging, with the highest temperatures recorded at 40c.
✓ Heat generation varied depending on factors such as charging duration
and ambient temperature.

Interpretation:

✓ Excessive heat generation can affect the performance and lifespan of

devices and charging equipment.
✓ Proper heat dissipation mechanisms may be necessary to mitigate
potential risks associated with wireless charging.

4. Comparative Analysis with Wired Chargers

Methodology:

✓ Compared the performance of the wireless mobile charger with

conventional wired chargers.
✓ Analyzed factors such as charging speed, efficiency, and user experience.

Results:

✓ Wireless charging was generally slower compared to wired charging,

with an average difference in charging time of 8%.
✓ However, users preferred wireless charging for its convenience and
flexibility despite the slightly slower speed.

Interpretation:

✓ The choice between wireless and wired charging depends on individual

preferences and priorities.
✓ Wireless charging offers convenience and freedom from cables, while
wired charging may be preferred for faster charging times.

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4.1conclusion
The wireless mobile charger project has provided valuable insights into the
practicality, performance, and user acceptance of wireless charging
technology. As the technology continues to evolve, addressing challenges such
as charging efficiency, distance limitations, and heat management will be
crucial for further enhancing the adoption and usability of wireless chargers in
the future.
Strengths
1.potential for innovation
2. Transparent reporting
3. Practical relevance
4. Rigorous methodology
5. Collaborative effort
Shortcomings
1. Time consuming
2. Equipment limitations
3. External validity
4. Bias risks
5. Lack of long- term analysis
4.3Recommedation
Based on the findings and analysis conducted in this project, several
recommendations are proposed to enhance the effectiveness, usability, and
acceptance of wireless mobile chargers:
Some of the recommendations are:
1. Optimize charging efficiency
2. Expand charging distance
3. Enhance heat management
4. Improve user experience
5. Educate consumers
6. Collaborate with standards organizations
7. Invest in research

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4.4references

1. Hughes electrical and electronic tenth edition, revised by John

Hiley, Kieth Browin and Ian Mckenzie Smith
2. Internet

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 TABLE OF CONTENTS
DECLARATION ......................................................................................................................................... 2
DEDICATION ............................................................................................................................................ 3
ABSTRACT ................................................................................................................................................ 4
BACKGROUND OF THE STUDY ................................................................................................................. 5
statement of problem ............................................................................................................................. 5
MAIN OBJECTIVE ............................................................................................................................. 6
SPECIFIC OBJECTIVE ........................................................................................................................ 6
1.5Organisation of the study .......................................................................................................... 8
1.5.2Block diagram.......................................................................................................................... 9
Literature review................................................................................................................................... 10
2.1Theoretical framework ............................................................................................................ 11
2.2Review of previous studies ...................................................................................................... 15
RESEARCH METHODOLOGY .................................................................................................................. 20
3.2 Data collection methods ......................................................................................................... 22
1. Data Cleaning: .......................................................................................................................... 22
2. Descriptive Statistics: ............................................................................................................... 22
Current amplifier .......................................................................................................................... 23
Transmitter coil ............................................................................................................................ 23
Receiver coil.................................................................................................................................. 24
Rectifier......................................................................................................................................... 24
LC oscillator circuit ....................................................................................................................... 24
Voltage regulator ......................................................................................................................... 25
3. Qualitative Analysis:................................................................................................................. 25
4. Interpretation and Reporting: ................................................................................................. 25
5. Inferential Statistics: ................................................................................................................ 25
6. Regression Analysis: ................................................................................................................. 25
7. Time Series Analysis: ................................................................................................................ 26
8. Factor Analysis:......................................................................................................................... 26
4.1DATA ANALYSIS ................................................................................................................................ 26
1. Charging Efficiency Analysis ...................................................................................................... 26
Methodology:................................................................................................................................ 26
results:........................................................................................................................................... 26
Interpretation: .............................................................................................................................. 27
2.Charging Distance Analysis ........................................................................................................ 27
Methodology:................................................................................................................................ 27

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Results: .......................................................................................................................................... 27
Interpretation: .............................................................................................................................. 27
3. Heat Generation Analysis .......................................................................................................... 27
Methodology:................................................................................................................................ 27
Results: .......................................................................................................................................... 28
Interpretation: .............................................................................................................................. 28
4. Comparative Analysis with Wired Chargers .............................................................................. 28
Methodology:................................................................................................................................ 28
Results: .......................................................................................................................................... 28
Interpretation: .............................................................................................................................. 28
4.4references ................................................................................................................................ 30

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