Wireless Charging Proposal

TAMIM ALKHONAINIUBONG UDOSSIENNADEEM QANDEEL

Wireless Power Charging System

Advisor:Dr. Yao

Committee:Dr. PetzoldDr. Glazos

OUTLINEo BACKGROUNDo PROBLEM STATEMENTo GOALS o REQUIREMENTS/ SPECIFICATIONSo PROJECT CHANGESo ACCOMPLISHMENTSo TESTING/ RESULTSo PROBLEMSo TIMELINEo BUDGETo CONCLUSIONo REFERENCES

BACKGROUND

Transmission of electrical power without the need of conducting wires.

Applications of wireless power systems could extend to higher power applications, like; electric vehicles.

Increase in demand for wireless power mobile charging devices.

A widespread interest in finding new applications in consumer products.

PROBLEM STATEMENT

The aim of the project is to produce a demonstration of wireless power system for charging a mobile phone and illustrate how magnetic coupling can be used to transfer energy wirelessly.

GOALS Illustrate how inductive power transfer work. Transferring sufficient power for charging a mobile phone based

on the Qi standard. Wireless power demonstrator system to charge multiple mobile

phones. Analyzing and improving power efficiency levels.

Wall outlet

Transformer Oscillator AC/DC

Rectifier

Regulators

Sensors

Switches Microcontroller

Bluetooth Communication

Module

LCD

Coils

Coils

Interface

Coupling

Phone

Transmitter

Receiver

High AC V/Low f

Low AC V/Low f

High f

Low AC V 3 V

7 V

5 V

7 V each

AC/DC

Rectifier

Regulators

System Block Diagram

Transmitter

Receiver

SYSTEM REQUIREMENTS

A transmitter base station that supplies wireless power to Qi phones.

A receiver that allows phones without Qi to be charged. Charge a phone wirelessly from a small distance of few

millimeter, possibly extending it to 1 cm or 2 cm on the long run. Charge the phone efficiently within a reasonable amount of time. Charge multiple phones on the long term. Ability to form communication between device and station. Displaying informative information to users on a screen.

SYSTEM SPECIFICATIONS

Parameter Symbol ValueOuter diameter do 43+-0.5mmInner diameter di 20.5+-0.5mmThickness dc 2.1+-0.5mmNumber of Turns per Layer

N 10

Number of Layers

– 2

A1 Primary Coil Design

SYSTEM SPECIFICATIONS

Receiver coils

Shielding of Power Transmitter Design A1

The alignment aid in this case would be a helped by the disc shaped magnet in the center of the coil. This magnet would align with a similar positioned magnet in the secondary coil.

Shielding must extend at least 2mm beyond the outer diameter of the primary coil and have a thickness of at least 0.5mm. A distance, ds = 1mm is need between the shielding and primary coil. The shield most comprise of a material chosen from a definite list of materials given in the Qi design specification.

SYSTEM SPECIFICATIONS

• The inductance of the primary coil, Lp along with the shielding and magnet is 24μH and the value of the series capacitor, Cp = 100nF.

• An input voltage of about 20V is required to the half bridge inverter.

Power Transmitter A1 design

PROJECT CHANGES

Alternative to Bluetooth for communication. Generating PWM from microcontroller. Charge only 2 phones rather than a bigger number. Change in circuit design. Use resonant frequency coupling.

ACCOMPLISHMENTS Generating a PWM signal with high frequency. Detecting objects with weight sensor. Showing informative messages on LCD. Charging light indicator. Receiver charging circuit. Transmitter charging circuit.

(Schematic)

• Phone type: iPhone 4s• Charging Voltage: 5 V• Required Current: 1 A• Required power: 5 W• Voltage Regulator (LM7805C) is used

to have an output of 5 V

(Results)

Receiver Unit Simulation TESTING/ RESULTS

TESTING/ RESULTS

Voltage Regulator (LM7805C) is used to have an output of 5 V.

Input using function generator. Vpp = 7 V Frequency = 110 KHz wave type: sine

Output readings: Voltage = 4.9 V Current = 0.7 A

Add pictures of breadboard, multimeter, function generator, and phone when it is being charged.

Receiver Unit Implementation

TESTING/ RESULTS

Input: function generator Time to be fully charged=

Input: coils (magnetic induction) Time to be fully charged =

Receiver unit

PROBLEMS

LCD buttons PWM 4 output Receiver circuit Transmitter circuit

FUTURE WORK Goals for the first semester include:

Design and Build the transmitter base station Design and build power system Design and Build the receiver Test one charging unit

Goals for the second semester include: Modify the design Bluetooth communication LCD Output

SCHEDULE

GANNT CHART

Task Start DateDuration (Days) End Date

Research 1/12/2015 34 2/15/2015Proposal 1/20/2015 31 2/20/2015Shopping 3/15/2015 15 4/1/2015Design &

Simulation 2/28/2015 5 3/5/2015Parts Testing 3/3/2015 7 3/10/2015

Transmitter Testing ????? ???? ????Receiver Testing 3/20/2015 30 4/19/2015Arduino Testing 3/23/2015 23 4/15/2015Progress Report 4/21/2015 14 5/5/2015Hardware Demo 4/27/2015 4 5/1/2015

Communication 9/15/2015 3010/15/201

5

Evaluation 10/20/2015 510/25/201

5

Improvements 10/25/2015 2111/15/201

5Final Hardware

Demo 12/7/2015 312/10/201

5

Final Report 11/20/2015 2612/16/201

5

BUDGETitem Number of units Price per unit

Sensors 3 $ 4.00

Transmitter Coils 3 $ 10.00

Receiver Coils 1 $ 8.00

Shipping   $ 30.00

Budget (2nd semester) Total cost is $ 77.00

item Number of units

Price per unit

LCD Display Board

1 $ 20.00

Transmitter Coils

1 $ 10.00

Receiver Coils 1 $ 8.00

Arduino 1 $ 30.00

Bluetooth Module

1 $ 35.00

Sensor 1 $ 4.00

USB breakout 1 $ 10.00

Shipping   $ 30.00

Budget (1st semester)Total cost is $ 147.00

CONCLUSIONS

What we hope to achieve in this project is a wireless charging system, that is convenient in it is operation, efficient in power transfer, smart in communication and data transfer.In this presentation, we highlighted four sections; power system, charging system, the control and communication system. Using the concept of induced coupling in strict adherence to the Qi Standard we should be able to successfully design a functional wireless power transmitter.

REFERENCES

1) The Qi interface specification, System Description Wireless Power Transfer Volume I: Low Power Part 1: Interface Definition, http://www.wirelesspowerconsortium.com/blog/11/qi-specification-available-for-download

2) Power By Proxy, Wireless Charging , http://powerbyproxi.com/wireless-charging/

3) Inductive Power Transfer, http://www.instructables.com 4) Engaged Primed: how wireless and inductive charging works,

http://www.engadget.com/2011/06/24/engadget-primed-how-wireless-and-inductive-charging-works/