5
www.ijemr.net ISSN (ONLINE): 2250-0758, ISSN (PRINT): 2394-6962 263 Copyright © 2016. Vandana Publications. All Rights Reserved. Volume-6, Issue-2, March-April 2016 International Journal of Engineering and Management Research Page Number: 263-267 Cost Effective Automatic Wireless Charging Abhishek Gupta 1 , Avadesh Sharma 2 , Amit Kr. Sharma 3 , Vishal Sukhwal 4 , Ravi Gurjar 5 , Anshuman Sahu 6 1,2 Senior Lecturer, Department of Electrical Engineering, SKIT, Jaipur, Rajasthan, INDIA 3,4,5,6 Pursuing B.Tech.-8 th Semester, SKIT, Jaipur, Rajasthan, INDIA ABSTRACT Mobile phone has become an important part in our today’s life. We are operating everything through mobile phones. Their charging imposes a big issue to users because they have to charge their phones daily or even multiple times per day. In this paper we present the concept of cost effective wireless charging which improves the power management in mobile phones. The main objective of this paper is to develop a concept of transferring power without use of any wires. With wireless power, efficiency is the more significant parameter. A large part of the energy sent out by the generating plant must arrive at the receiver or receivers to make the system economical. The most common form of wireless power transmission is carried out using direct induction followed by resonant magnetic induction. This concept is called as Resonance Inductive Coupling (RIC). In this paper, a wireless power transfer system is designed with automatic phone detection, time & proximity settings. The 16×2 LCD displays the status with time & proximity settings. Keywords---- PIC, PWM Modulator, IR, RIC, Interfacings. I. INTRODUCTION Wireless Power Technology [1] is emerging as a practical solution for providing energy for devices at remote distances. This paper will focus on the technology of inductively coupled [2] wireless power transfer (WPT). This provides a safe, efficient, and convenient method of transferring power to remote static devices, or recharging portable devices like smartphones. This revolves around the principle of Resonant Inductive Coupling (RIC) [3] which can be applied to acquire maximum transfer of power contactless, thereby facilitating the individual to charge his electronic equipment efficiently. It was also reported that magnetically coupled resonance WPT has several valuable advantages, such as efficient midrange power transfer, non-radiative, and nearly Omni-directional. It is certain that these properties will help to improve the performance of current wireless power transfer systems. The experiment is based on the transmission of a non-radiative energy from transmitter coil to the receiver coil using Resonant Inductive Coupling. The resonant inductive coupling technique is the principle method employed in short and mid-range WPT systems [4]. This paper implies wireless transmission of power using RF waves. A suitable charging circuitry is demonstrated which can capture high frequency signal and convert it into DC signal. II. TECHNOLOGY 2.1 Inductive Coupling Two devices are said to be mutually inductively coupled or magnetically coupled when they are configured such that change in current though one wire induces a voltage across the ends of the other wire by electromagnetic induction. This is due to the mutual inductance. Faraday’s laws of electromagnetic induction specifies the cause of induced EMF. Figure 1: Inductive Coupling 2.2 Resonance Inductive Coupling (RIC) RIC is the combination of both inductive coupling and resonance [5]. Using the concept of resonance it makes the two objects to interact each other very strongly.

Cost Effective Automatic Wireless Charging - IJEMR · Cost Effective Automatic Wireless Charging . Abhishek Gupta. 1, ... mobile phones. ... increased by using microwaves for wireless

  • Upload
    trantu

  • View
    215

  • Download
    0

Embed Size (px)

Citation preview

www.ijemr.net ISSN (ONLINE): 2250-0758, ISSN (PRINT): 2394-6962

263 Copyright © 2016. Vandana Publications. All Rights Reserved.

Volume-6, Issue-2, March-April 2016

International Journal of Engineering and Management Research

Page Number: 263-267

Cost Effective Automatic Wireless Charging

Abhishek Gupta1, Avadesh Sharma2, Amit Kr. Sharma3, Vishal Sukhwal4, Ravi Gurjar5, Anshuman Sahu6 1,2Senior Lecturer, Department of Electrical Engineering, SKIT, Jaipur, Rajasthan, INDIA

3,4,5,6Pursuing B.Tech.-8th

Semester, SKIT, Jaipur, Rajasthan, INDIA

ABSTRACT Mobile phone has become an important part in our today’s life. We are operating everything through mobile phones. Their charging imposes a big issue to users because they have to charge their phones daily or even multiple times per day. In this paper we present the concept of cost effective wireless charging which improves the power management in mobile phones. The main objective of this paper is to develop a concept of transferring power without use of any wires. With wireless power, efficiency is the more significant parameter. A large part of the energy sent out by the generating plant must arrive at the receiver or receivers to make the system economical. The most common form of wireless power transmission is carried out using direct induction followed by resonant magnetic induction. This concept is called as Resonance Inductive Coupling (RIC). In this paper, a wireless power transfer system is designed with automatic phone detection, time & proximity settings. The 16×2 LCD displays the status with time & proximity settings. Keywords---- PIC, PWM Modulator, IR, RIC, Interfacings.

I. INTRODUCTION

Wireless Power Technology [1] is emerging as a practical solution for providing energy for devices at remote distances. This paper will focus on the technology of inductively coupled [2] wireless power transfer (WPT). This provides a safe, efficient, and convenient method of transferring power to remote static devices, or recharging portable devices like smartphones. This revolves around the principle of Resonant Inductive Coupling (RIC) [3] which can be applied to acquire maximum transfer of power contactless, thereby facilitating the individual to charge his electronic equipment efficiently.

It was also reported that magnetically coupled resonance WPT has several valuable advantages, such as efficient midrange power transfer, non-radiative, and nearly Omni-directional. It is certain that these properties will help

to improve the performance of current wireless power transfer systems. The experiment is based on the transmission of a non-radiative energy from transmitter coil to the receiver coil using Resonant Inductive Coupling. The resonant inductive coupling technique is the principle method employed in short and mid-range WPT systems [4]. This paper implies wireless transmission of power using RF waves. A suitable charging circuitry is demonstrated which can capture high frequency signal and convert it into DC signal.

II. TECHNOLOGY 2.1 Inductive Coupling

Two devices are said to be mutually inductively coupled or magnetically coupled when they are configured such that change in current though one wire induces a voltage across the ends of the other wire by electromagnetic induction. This is due to the mutual inductance. Faraday’s laws of electromagnetic induction specifies the cause of induced EMF.

Figure 1: Inductive Coupling 2.2 Resonance Inductive Coupling (RIC)

RIC is the combination of both inductive coupling and resonance [5]. Using the concept of resonance it makes the two objects to interact each other very strongly.

www.ijemr.net ISSN (ONLINE): 2250-0758, ISSN (PRINT): 2394-6962

264 Copyright © 2016. Vandana Publications. All Rights Reserved.

Inductance induces current in the circuit. As seen in the figure 2, the coil provides the inductance.

Figure 2: Resonant Inductive Coupling

Energy will be shifting back and forth between magnetic field surrounding the coil and electric field around the capacitor. Here the radiation loss will be negligible. 2.3 Pulse-Width Modulation (PWM)

Pulse-width modulation is a digital technique for varying the amount of power delivered to an electronic component. The simplest and most flexible PWM is generated by a microcontroller. The average value of voltage (and current) fed to the load is controlled by turning the switch between supply and load on and off at a fast pace. The longer the switch is on compared to the off periods, the higher the power supplied to the load is. The PWM switching frequency has to be much faster than what would affect the load, which is to say the device that uses the power.

The main advantage of PWM is that power loss in the switching devices is very low. When a switch is off there is practically no current, and when it is on,

there is almost no voltage drop across the switch. PWM also works well with digital controls, which, because of their on/off nature.

Duty Cycle is the ratio of ON time to total time of switch. Duty Cycle is varied to get variable output power. Maximum value of duty cycle is 1. At duty cycle of 1, output power obtained is maximum. 2.4 PIC Microcontroller

It is a 8-bit, 40 pin CMOS flash type microcontroller with following features:

• High performance RISC CPU • Up to 8K x 14 words of FLASH Program Memory, Up

to 368 x 8 bytes of Data Memory (RAM) • Two Capture, Compare, PWM modules • Wide operating voltage range: 2.0V to 5.5V • High Sink/Source Current: 25 mA • Low power consumption.

www.ijemr.net ISSN (ONLINE): 2250-0758, ISSN (PRINT): 2394-6962

265 Copyright © 2016. Vandana Publications. All Rights Reserved.

Figure 3: Circuit Diagram of the System

www.ijemr.net ISSN (ONLINE): 2250-0758, ISSN (PRINT): 2394-6962

266 Copyright © 2016. Vandana Publications. All Rights Reserved.

Figure 4: Power Supply of the System

III. ASSEMBLY & WORKING OF THE CIRCUIT

3.1 Operation

• The 230V, 50Hz power supply from socket is given to 12V, 5A step down transformer which steps down it to 12V AC. 12V AC is then given to bridge rectifier which converts it into 12V pulsating DC. 12V pulsating DC is then filtered by capacitor filters and then regulated by 7812 voltage regulator.

• 12V DC supply is used by some components like ULN2003 driver. 12V DC supply is converted into 5V DC supply by 7805 voltage regulator & then filtered by capacitor filters to remove harmonics. 5V DC supply is used by components like 16×2 LCD, PIC16F73 microcontroller, etc. The operating data of components is collected [8] & system is designed accordingly.

• The PIC16F73 microcontroller is interfaced with 16×2 LCD at port B, ULN2003 driver IC at port C, 3 IR sensors with brake pedal at port A & 4 control switches.

• PWM modulator consisting of MOSFET switches is used to on-off the 12V supply to ULN2003 IC. PWM modulator is connected to RC2 bit of microcontroller. With logic 0 on RC2 bit, it is in cut-off & with logic 1 it operates. ULN2003 IC drives the relays which are connected to the ferrite core DC transformer.

• The high frequency 12V input voltage due to PWM modulator given to step-up ferrite core transformer through relays gives high frequency (radio frequency) & high voltage output.

• The high frequency & high voltage output is given to the transmitter coil which generates an oscillating magnetic field [6].

• A voltage is induced (EMF) in receiving coil placed in the phone when receiving coil links with the changing magnetic flux =of transmitting coil. A current flows in the receiving coil when load is

connected across it. The receiving coil’s output voltage & current is rectified & regulated. Then regulated output is given to the charging pins the phone’s battery which charges it.

• More the frequency of ferrite core output voltage then more will be the distance upto which wireless power transfer can take place. High voltage is used to maximize wireless power transfer & reduce losses.

• The power transfer is maximum at resonant frequency. The two coils are tuned at the same resonant frequency & receiving coil in the phone receives the power through the magnetic field generated by the transmitting coil.

• Heat Sink is used with MOSFETS to dissipate heat generated due to high frequency switching.

3.2 Automation • The system is designed to work automatically by

using IR sensors, Proximity setting & Time setting. • When the phone is placed near the transmitter coil,

the IR sensors detect the phone & sends signal to the microcontroller which processes it & gives signal to ULN2003 driver IC which drives the relays & closes their contacts. The coding of PIC16F73 microcontroller is done for various interfacings which are present. [7]

• On closing of relay contacts, the transmitter coil is energised & generates a oscillating magnetic field which links with receiver coil & induces EMF in it. Current flows through load connected across receiver coil & charges the battery of smartphone. This sensing increases efficiency & reduces human effort.

• The 4 switches connected with the microcontroller used for controlling are:

(a) 1st switch is for ON-OFF of time & proximity control. (b) 2nd switch is for selecting mode – Time mode & Proximity mode. (c)3rd & 4th switch is for increasing & decreasing the time & proximity level.

www.ijemr.net ISSN (ONLINE): 2250-0758, ISSN (PRINT): 2394-6962

267 Copyright © 2016. Vandana Publications. All Rights Reserved.

• Time setting is employed which charges the battery only for a fixed time. On selecting time mode by 2nd

• Proximity setting is employed for setting up output power level (0% - 100%) for different types of batteries. On selecting proximity mode by 2

switch & setting up charging time helps to stop overcharging when phone is kept on charging for long time by mistake.

nd

• The 16×2 LCD displays the time & proximity settings.

switch & setting up output power level, the duty cycle of PWM modulator is varied. It helps in setting up required output current for different batteries.

• Two LED’s shows the ON-OFF status of charging. Red LED glows when no charging is taking place &

green LED glows when charging is taking place.

IV. SNAPSHOT OF THE SYSTEM

V. RESULTS

In this experiment maximum output power is 10W with 5V output voltage & 2A maximum output current. The output power (i.e. output current) can be reduced by proximity setting. On using 50% proximity setting (i.e. 0.5 as duty cycle) mobile phone charges upto 12 cm. The 3.7V mobile phone lithium-ion battery is charged successfully in this experiment.

VI. CONCLUSION

The goal of this paper was to design and implement a wireless power transfer system via magnetic resonant coupling. After analyzing the whole system step by step for optimization, a system was designed and implemented. This method of automatic charging the phone is cost effective as no wires are required for charging. Also, it provides greater convenience and ubiquity for charging of everyday devices.

VII. FUTURE SCOPE

• More research is needed in field of wireless power transfer for increasing the efficiency & decreasing cost. The distance of wireless power transfer can be increased by using microwaves for wireless power transfer [9].

• This method of charging can be used for most of the phones by setting up receiver coil unit in the phones. Reduction in the size of coil in future will certainly boost the use of wireless charging.

• Solar panels can be used instead of AC power supply to reduce dependence on supply & increase the mobility of the charger [10].

REFERENCES

[1] A. Costanzo, M. Dionigi, D. Masotti, M. Mongiardo, G. Monti, L. Tarricone, and R. Sorrentino, “Electromagnetic Energy Harvesting and Wireless Power Transmission: A Unified Approach,” Proceedings of the IEEE, vol. 102, no. 11, pp. 1692-1711, Nov. 2014. [2] N. Tesla, “Apparatus for Transmitting Electrical Energy,” US Patent Number 1,119,732, Issued in Dec. 1914. [3] A. Kurset al. “Wireless Power Transfer via Strongly Coupled Magnetic Resonances,” SCIENCE, vol. 317, pp. 83-86, July 2007. [4] Prof. Vishal V. Pande, Pooja D. Doifode, Dhanashree, S.Kamtekar, Prashant P.Shingade– “Wireless Power Transmission Using Resonance Inductive Coupling” – IJERA, ISSN : 2248-9622, Vol. 4, Issue 4( Version 9), April 2014, pp.46-50. [5] J. C. Maxwell, “A Treatise on Electricity and Magnetism, 1873 [6] Z. N. Low, R. Chinga, R. Tseng, and J. Lin, “Design and Test of a High Power High-Efficiency Loosely Coupled Planar Wireless Power Transfer System,” IEEE Trans. Ind. Electron., vol. 56, no. 5, pp. 1801-1812, May 2009. [7] Raj Kamal, “Embedded System - Architecture, Programming and Design”, Tata McGraw Hill Publisher, 2nd

[8] http://

edition, 2008.

[9] www.datasheetcatalog.com

[10] http://www.witricity.com

http://www.wirelesspowerconsortium.com