Wireless Power Transfer Through Coil

Project and Seminar Material For Electrical Electronics Engineering EEE

Abstract

As power requirements for portable devices increase, consumers are looking for easy-to-use charging solutions that can be deployed in a wide array of environments such as home, office, automobiles, airports, schools and more. Wireless charging uses an electromagnetic field to transfer energy between two objects. This is usually done with a charging station. Energy is sent through an inductive coupling to an electrical device, which can then use that energy to charge batteries or run the device.

Chapter One

1.0 Introduction

1.1 Background of the Project

Inductive power transfer (also known as wireless power transfer) uses an electromagnetic field to transfer energy between two objects. This is usually done with a charging station. Energy is sent through an inductive coupling to an electrical device, which can then use that energy to charge batteries or run the device.

This device use an induction coil to create an alternating electromagnetic field from within a charging base, and a second induction coil in the portable device takes power from the electromagnetic field and converts it back into electric current to charge the battery. The two induction coils in proximity combine to form an electrical transformer. Greater distances between sender and receiver coils can be achieved when the inductive charging system uses resonant inductive coupling. Recent improvements to this resonant system include using a movable transmission coil (i.e. mounted on an elevating platform or arm) and the use of other materials for the receiver coil made of silver plated copper or sometimes aluminium to minimize weight and decrease resistance due to the skin effect.

1.2 Problem Statement

The invention of this device brought solution to problem seen in the wired mobile charger and introduce the following advantages [K. Oguri, 2000].

Protected connections – No corrosion when the electronics are all enclosed, away from water or oxygen in the atmosphere. Less risk of electrical faults such as short circuit due to insulation failure, especially where connections are made or broken frequently.
Low infection risk – For embedded medical devices, transmission of power via a magnetic field passing through the skin avoids the infection risks associated with wires penetrating the skin.
Durability – Without the need to constantly plug and unplug the device, there is significantly less wear and tear on the socket of the device and the attaching cable.
Increased convenience and aesthetic quality – No need for cables

1.3 Objective of the Project

The objective of this project is to design a wireless power transmission system using inductive coupling is to charge a low power device using wireless power transmission. This is done using charging a resonant coil from AC and then transmitting subsequent power to the resistive load. The project is meant to charge a low power device quickly and efficiently by inductive coupling without the help of wires.

1.4 Limitation of the Project

Slower when using as charging device – Due to the lower efficiency, devices take longer to charge when supplied power is the same amount.
More expensive – Inductive charging also requires drive electronics and coils in both device and charger, increasing the complexity and cost of manufacturing.
Inconvenience – When a mobile device is connected to a cable, it can be freely moved around and operated while charging. In most implementations of inductive charging, the mobile device must be left on a pad to charge, and thus can’t be moved around or easily operated while charging.
Incompatibility – Unlike (for example) a MicroUSB charging connector, there are no universal standards for inductive charging, thus necessitating various different chargers for different devices.Newer approaches reduce transfer losses through the use of ultra thin coils, higher frequencies, and optimized drive electronics. This results in more efficient and compact chargers and receivers, facilitating their integration into mobile devices or batteries with minimal changes required. These technologies provide charging times comparable to wired approaches, and they are rapidly finding their way into mobile devices.
Distance constraint: Field strengths have to be under safety levels
Initial cost is high
In RIC, tuning is difficult
High frequency signals must be the supply Air ionization technique is not feasible

1.5 Applications of the Project

Near-field energy transfer
Electric automobile charging Static and moving
Consumer electronics
Industrial purposes Harsh environment Far-field energy transfer
Solar Power Satellites
Energy to remote areas
Can broadcast energy

1.6 Scope of the Project

Wireless charger using inductor (coil), is one of the effective ways to transfer power between points without the use of conventional wire system. Wireless power transmission is effective in areas where wire system is unreachable or impossible. The power is transferred using inductive coupling, resonant induction or electromagnetic wave transmission depending on whether its short range, mid-range or high range.

In this project, the wireless power transfer works mainly on the principle of inductive coupling. With this inductive coupling idea, we are trying to transfer power wirelessly to charge low power devices, such as mobile phones, cameras, wireless mouse etc.

1.7 Methodology

To achieve the aim and objectives of this work, the following are the steps involved:

Study of the previous work on the project so as to improve it efficiency.
Draw a block diagram.
Test for continuity of components and devices,
Design was carried out.
Studying of various component used in circuit.
Construct the circuit.
Finally, the whole device was cased and final test was carried out.

1.8 Project Work Organisation

The various stages involved in the development of this project have been properly put into five chapters to enhance comprehensive and concise reading. In this project thesis, the project is organized sequentially as follows:

Chapter one of this work is on the introduction to this study. In this chapter, the background, significance, objective, limitation, application and scope of this study were discussed.
Chapter two is on literature review of this study. In this chapter, all the literature pertaining to this work was reviewed.
Chapter three is on design methodology. In this chapter all the method involved during the design and construction were discussed.
Chapter four is on testing analysis. All testing that result accurate functionality was analyzed.
Chapter five is on conclusion, recommendation and references.

Chapter Five

Conclusion and Recommendation

5.1 Conclusion

From this Wireless power transmission mobile charger circuit using inductive coupling experiment, we conclude that wireless charging through inductive coupling is a better way for future energy transmission systems, that is wireless electricity, because with this technology we can transfer power wirelessly to charge electronic equipment, vehicles, etc.

5.2 Recommendation

In the implementation of this project what has proved most difficulties is the selection of the right value of components some were using two diode (the maraine value), in order to have a perfect full wave rectification, we made use of four diodes and the and a functional portable battery is been designed and constructed.

Due to the possibility of this, it has surely put smiles on the face of most people like some motorist who has long been finding it difficult charging there own batteries at their homes and at their convenient time.