# Conical Wireless Power Transfer System Sample Assignment

Thesis on design and construction of a conical wireless power transfer system

Introduction

Motivation

There has been a serious development in the overall technology used in the maintenance of the different electronic devices like the television, phones and other integrated circuits in the modern era in the society (Wang et al. 2015). The evolution of the new and advanced electronic devices has also resulted in the use of the advanced electronic devices and also maintain of the advanced design in the building of the materials used to build the equipments (Bergsrud and Straub, 2014). The design of the equipments is made in a more advanced way and also in a more systematic way to rightly deliver the right quality of the technology for the different people in the market.

For making the various types of the wireless power transfer system, the advanced and modern designs are used for improvement of the system. Although it helps to it helps to develop the entire system of the wireless power. Moreover it also assist in creating the correct and accurate power which is necessary for the controlling and managing the electronic devices. The system uses the electromagnetic spectrum for maintaining the safety and security (Chen et al. 2018). The wireless power transfer system is designed with the well constructed components which help to managing the betterment for the economy. The market was being tried to build the ore sensitive that is compared to the technology (Wang et al. 2015).

This underlined chapter introduces the motivation for the motivation of the present work. The first section consists of the overall theoretical background of the wireless power transfer system. The second section includes the literature review (Krikidis et al, 2014). The third sections consist of the important contributions done to the present work carried out in the underlined study. The last section c consists of the present organizations that contribute to the overall thesis of the study in details.

Theoretical background

Hertz was the first person who introduced the application of the procreation of the various waves of the radio. The wireless power transfer system or the electricity is showed an accurate capacity to the transmission of the power of the electricity which observed the source of the power. It is necessary to load the electric power without the application of the various wires present in the area (Tuna et al. 2014). Thus the wireless power system is useful to the radio and the television also.

To achieve the entire efficiency of the power is very important in the wireless power system. But it is difficult to design effectively of the wireless power electricity. It is built with the high reverberation power and it is also needed the magnetic wires accordingly. As per the view of (Dai et al., 2017) the wireless power transfer system needs the power which enables the systematic design approach. It is used for the safety reason of taking the electric reverberation power in the transfer system.

The non-radiation and radiation power system is classified by two different groups in the wireless power system (Tong et al. 2016). The radiation power system is relying on the entire excitation of the wireless power transfer system by which the radiation receives the power from the high source of the electricity (Zargham and Gulak, 2015). The power of the radiation released from the original source which goes through over the magnetic waves which is far distance from the electromagnetic (Fukunari et al. 2017). On the other hand, the power transfer system of non-radiated mainly relies on the magnetic wire coupled loops.

(Source: Valenta and Durgin ,2014)

The most applications uses a high magnetic coupling structure for the achievement of the high power efficiency in the wireless power transfer system .The achievement of the high magnetic coupling structure is very much difficult as it reduces the effect of the magnetic coupling as the overall distance between the transmission system increases as it is highlighted in the above diagram. It is needed to extend the overall power transmission range of the wireless power transfer system to be more useful and also it helps in supporting the use of the different applications that requires a high amount of magnetic coupling energy to help in the increase of the efficiency of the overall system (Valenta and Durgin ,2014).

There has been use of several or numerous range of the methods to increase the overall pick up of the power efficiency in the system to help in the increasing of the efficiency of the system for the use of the different appliances or applications in the further study.

History of the wireless power transfer system

The wireless power transfer system is an useful system that is used to transmit the device or the there is active transformation of the energy with the help of different physical wires by the link that helps to establish the correct radiating system for the generation of the enough power source for the transmission of the electromagnetic field in the system.

According to Thilina et al. (2015), it helps in the correct generation of the electromagnetic field for the different system and helps in achieving the correct power for the development of the system or the applications in the future. It came in to the knowledge of the people after the year 1930. The period before 1931 witnessed no chance or opportunities for the different people to know that there is a need of the correct source of transmitting power required to generate a powerful electromagnetic field within the applications that helps in the correct utilization for the generation of power for the human beings in the society(Park et al. 2015).

In the recent era or in the current period the use of the wireless power transfer system has helped in the correct gain of the knowledge used to identify the overall need of the system to emit the correct power source for emitting the correct electromagnetic power for helping in the overall transmitting of the different types of applications used in the system (Yin et al . 2015). It helps to highlight the applications of the wireless power transfer system a d also help to identify the correct history of the system in details from the early period (Boshkovska et al. 2015).

Physics of the wireless power transfer system

The transfer system of wireless power is an efficient system that is used for the production of the different applications used for the applications needed by the human beings. The working of the wireless power transfer system depends on the overall Maxwell’s form of energy equation or law (Ding et al. 2015). It states that the various transmitters used in the system are used to transmit the different energy to the system and it helps in the form of receiving of the correct form of energy as applied in the other forms of the wireless communication system as used by the human beings in the modern era (Pan et al. 2015).

The various kinds of electromagnetic fields associate with the wireless power transfer system are embed or helps in the various device that makes use of the wireless power transfer principle for the safety use of the individuals in the society (Diekhans and De Doncker , 2015). The exposure to the strong electromagnetic fields in the wireless power transform system also helps to radiate a strong electromagnetic energy to the different types of individuals in the market (Duarte et al. 2014).

The wireless power transfer system allows that there needs to have a correct form of communication between the transmitter and the receiver in the spreading of the right energy between the two devices and it results in the correct flow of the current between the two selected devices that uses the electromagnetic form of energy omitted or generated from the wireless power transfer power system (Gunduz et al. 2014).

The working of the wireless power transfer system relies over the concept of the radiation between the far area as well as the near field techniques (Lee and Han, 2015). It helps in the correct form of radiation between the two forms and helps to maintain the correct form of electromagnetic form of energy between the different devices that uses the wireless power transfer system (Yang et al. 2015). The form of transmission techniques, the amount of power hat has been transferred within the system and the overall requirements of the proximity are very much influential in determining the nature of the radiation system used (Dai and Ludois, 2015). It can be a far field technique of radiation used by the system or a near field technique of radiation used by the system (Hu et al. 2014).

The locations of the different antenna applied for creating the wireless power transfer system is used for the transmission of the electromagnetic waves that also helps to utilize the correct power for emitting the correct radiating power of the system. It also help in the transmission of the different radiating forms of energy used in the types of oscillating frequencies and also the types of electric fields are very much dependent on each other in the performing of the applications of the systems under the principle of the wireless power transfer system. The capacitive and the magnetic coupling used in the forms of the applications used under the principle of the wireless power transfer system helps in the correct utilization of the technique to radiate the correct form of the electromagnetic energy in the necessary application using the wireless power transfer system.

The locations for the antenna are also a necessity for the correct availability of the correct form of electromagnetic radiation for the use of the different applications using the wireless power transfer systems. There is a availability of the transition region that exists in the overall region between the far and near field of the radiation field. The two differ rent fields help in the correct identification of the different location of the antennas that help to determine the correct necessity of the forms of the electromagnetic radiation in the wireless power transfer system. The narrow source of beam that is emitted from the far field transfer used in the wireless power transfer system is also known as the power beaming.

The power beaming technique that emits a narrow source of beam in the wireless power transfer system in the different far fielding techniques are used in the types of hoe applications for the use of the human beings in the form of the microwave radiation or the high power lasers for the transmission of the overall source of the radiation of over the long distances in the radiating field used in the wireless power transfer system. It helps in the correct radiation of the transmission of the energy over the long distances and it helps as a useful source of the emission of the electromagnetic field in the system.

The different types of radiating source emitting in the fielding techniques of the wireless power transfer system acts as an useful source of the emission of the power over the long and the short distances in the forms of energy. It helps in the maintenance of the correct form of source to the different human beings by the radiation of the electromagnetic field in the system.

Applications of the wireless power transfer system

The overall forms of the technology used by the wireless power transfer system have been used in the maintenance of the applications used by the types of human beings in the society. The system focuses on the use of the maximization of the different techniques used for the transfer of the power and also in the use of the magnetic coupling techniques used in the coupling system of the coil used in the wireless power transfer system.

The different types of advanced vehicles used in the forms in the places in the world uses a system of the advanced mode of the wireless power transfer system to help in the correct utilization of the techniques to help in the correct functioning of the forms of the system.

The energy transmitted from the wireless power transfer system is also used in the functioning of the advanced mode of the types of vehicles and also the different types of the latest advanced machineries used in the overall development of the energy transmitted by the receivers to help in the correct generation of the electromagnetic power used in the system.

It is also used to produce the correct form of the transmission of the energy and also the use of the energy makes it more convenient for the use of the latest technology in the vehicles and also helps to formulate the correct form of electromagnetic power in the vehicles.

Classification of Wireless power transfer system

The transfer system of wireless power is classified in three following types of radiation which available in the entire distance of the radioactive ranges. These radioactive ranges are described below:

The different types of the magnetic couples are applied for designing the short range radiation. It is used for restrict the preparatory pair wire links. Thus it helps for transmitting the accurate power to the various kinds of devices (Hu and Wang, 2015). This radiation is placed on the multiple kinds of the plants in the system. But it is limited for rotating the power to 280 mw over 1 cm.

The different types of the magnetic couples are applied for designing the medium range radiation. It is used for restrict the preparatory pair wire links. Thus it helps for transmitting the accurate power to the various kinds of devices (Ta et al. 2015). This radiation is placed on the multiple kinds of the plants in the system. But it is limited for rotating the power to 14 MHz.

The different types of the magnetic couples are applied for designing the long range radiation. Its main source is electromagnetic waves. It is used for restrict the preparatory pair wire links. Thus it helps for transmitting the accurate power to the various kinds of devices (Timotheou et al.

2015). This system covers the long range distance for the safety to the human beings.

Literature review

According to Kong et al. (2017), the wireless power system is designed in a generalized structure. Moreover, it is built in a systematic way for transmitting the radioactive waves from the various regions. This region can be the low ability region or high ability region. On the contrary Li et al. (2016), states this system is also used for providing the charge to the different vehicle, cycles, and so on to betterment use of the machineries. Due to the development of the wireless power transfer system, the different radiation is used for improving the entire technology. As per the view of MacVittie et al., (2015), it also assists to minimize the ohmioc loss in the resonators by using the Meta materials.

According to Lin et al. (2017), the success of the high magnetic paring framework is very much difficult as it reduces the effect of the magnetic coupling. The overall distance between the transmission systems maximizes as it is highlighted in the above diagram. It is needed to extend the overall power transmission range of the wireless power transfer system to be more useful and also it helps in supporting the use of the different applications that requires a high amount of magnetic coupling energy to help in the increase of the efficiency of the overall system. On the other hand, Lu et al. (2015) stated the design of the wireless power system is essential as it helps to maintain the sleekness of the entire system for transferring the power from the region in the radioactive area.

Furthermore Luo et al. (2016), states that the well structured full wave electromagnetic solver is used in the solving of the different transmission and receiving of the different waves located in the medium (Bosshard and Kolar, 2016). It helps to customize and the organization of the different objects by the use or introduction of different features like the parameterization and the scripting of the different objects. It helps in the overall formation of the different types of projects by using the General user interface principle (Samanta and Rathore, 2015). According to Nemitz et al. (2016) the different types of radiating source emitting in the fielding techniques of the wireless power transfer system acts as an useful source of the emission of the power over the long and the short distances in the forms of energy. It helps in the maintenance of the correct form of source to the different human beings by the radiation of the electromagnetic field in the system (Song, et al. 2017).

According to Perera et al. (2015) the overall distance between the two transmitters have a great effect on the efficiency encountered by the system and it has no influence on the other parameters of the system like the height of the coil, radius of the loop, radius of the system and the angle between the receiver and the transmitter in the system (Xiong et al .2015). The above results depict that the bringing of the two transmitters in close relation to each other in the different coils causes a total reduction in the overall efficiency and the separation of the two transmitter coils between each other are far away from each other by a measurement (Radziemski and Makin, 2016).

According to Shi et al. (2014), In order to study the overall effect of t he radius of the transmitter loop in the two systems of the wireless power transfer system the two transmitters are taken at a distance of 25mm and the distance between the transmitters and the loop are set at a distance of about 50 mm depending on the overall minimal value as obtained in the underlined sections of the underlined study. The overall radius of the transmitter loop is set up at a distance of about 190mm to 300mm in the system (Sikder et al. 2017). The system is useful for charging of the electronic devices or the components. It helps to maintain the accurate state of the correct procedures for extending the entire electric region from the various fields with the effective methods. Furthermore, it assists to manage and control the overall stability of the wireless power system (Neath et al. 2014).

Research objectives

The basis of the requirements used to design a sleek and a systematic design of the wireless power transfer system the underlined research objectives might be classified and deduced accordingly:

• Design of a more systematic and coupled wireless power transfer system.
• Design of a more sleek coiled system to reduce the frequency of the electromagnetic waves used in the system.
• Design a more harvesting power for the generation of more power to the overall circuit power of the system to deliver a more optimized wireless power transfer system

CHAPTER 2

Elements of wireless power transfer system

Introduction

There wireless power transfer system consists of different types of materials or elements that help in the effective transmission of the radiating energy in the fields of energy. The various kinds of elements among the field of the wireless power transfer system consist of the inductive coupling, capacitive coupling, and resonant coupling techniques (Shin et al. 2014). The magnetic coupling consists of magnetic wires which helps in the different forms of the radiation of the wires in the different field and it helps in the correct radiation of energy within the different wires and helps in the correct resonance of the different radiations of the different type of the field consisting in the different wires consisting in the different magnetic fields (Carvalho et al.

2014).

There are two different types of current passing through the different coil in the radiating field. .

The two different coils include the direct current and the alternating current (Choi et al. 2015). The two currents pass through the different coils and help in the correct coupling resonance of the two different coils in the magnetic field and create a sense of a strong electric field in the different coils passing through the different electromagnetic fields.

The different types of coils helps to increase the overall inductive coupling efficiency depends on the different types of parameters like the placement of the coil in the wireless power transfer system and also help in the coupling of the core material present in the wireless power transfer system. The different types of the transformers that are applied in the coupling efficiency in the system are the use of the correct form of iron or steel while the metal doctor coils makes use of the air in the wireless power transfer systems. It helps in the correct form of passing of the current between the two coupling wires and helps in creating a strong power that helps to increase the overall efficiency if the different types of coils used in the system.

Fig 2.1 Magnetic fields around a coil that is carrying current

There are different designs in coils which has been developed or evolved in the last era. It has helped in the passing of the magnetic field through the different types of wires and creates an electromagnetic field (Li and Mi, 2015). The different types of coils include the spiral, a helical, inverse coil which helps in the right passing or the functioning of the different magnetic fields in the electromagnetic field.

Fig: 2.2 (a) spiral coil (b) helical coil (c) inverse conical coil

(Source: Mi et al. 2016)

Parameters of coils

The different types of electromagnetic waves passing through the different coils are a type of the different electromagnetic radiation which are organized and structured in the correct way depending on the correct frequency of the different types of waves. The frequency is expressed as the amount or the number of different repletion of the different indices that occurs at the regular interval of time and it helps to radiate the correct type of electromagnetic waves at the correct schedule of time (Mi et al. 2016). The frequency is measure or expresses in terms of hertz which helps in measuring the total number of the occurrence of the cycles occurring at a regular interval of time. It helps in the correct measurement of the different types of cycles of the number of the regular intervals at that moment of time (Huang and Lau, 2014). The frequency is defined as the reciprocal of the occurrence of the time occurred at that period of time. It is expressed in the following way in the study.

F= 1/f

Inductance

It is expressed as the characteristic of the total electrical circuit that helps in the starting, opposing and the valuing of the current and has the same effect on the overall effect of the current in the electrical circuit and also effects the movement of the flow of the inertia within the different coils located in the different magnetic coils (Badr et al. 2017). It requires a lot more energy during the starting of the object in comparison to the stopping of the object.

The faraday’s law of induction in the electromotive force is the primary law of the electromagnetism that helps in the correct development of the production of the magnetic field in an electrical circuit and the effect of the development of the field of the electric region on the development of the electric flow within the circuit (Zhong et al. 2015). It is the basic or the primary operating source for the different types of the electric generators, motors and the different types of the solenoids.

The electromotive force is developed during the development of e relation between the conductor and the magnetic field that occurs within the magnetic coil. It is the difference between the differences in the charge of the potential volts which also exists in the two different points in the electrical circuit (Moon et al. 2014). The electromotive force is developed by the overall action of the electrons and the magnetic field working in case of the conductor. It helps to develop the overall process of increasing or producing the right electromotive force in case of the development of the different current generate in the circuit (Aldhaher et al. 2014).

Fig 2.3: Generation of an emf in an electrical conductor.

Self –inductance

The perfect straight conductor also contains a small amount of small inductance in the conductor which helps to produce the right electromagnetic field in the conductor and develop he right circuit within the conductor. According to Bi et al. (2016), the current changes and the magnetic field also changes within he conductor and results in the production of the relative motion between the conductor and the magnetic field and develops a phenomenon called

electromagnetic force within the semiconductor.

The principle works on the Lenz’s law which evaluates or expresses that any electromotive force produced in any circuit is always in a direction to the overall effect of the current produced in the circuit. It helps to create a current in the opposite direction of the current and it results in the creation of the negative electromotive force in the circuit (Esteban et al. 2015). The conductors have current and hence it also has a vast amount of inductance in the body of the different circuits produced as a result of the underlined law.

The different types of inductors are divided in the wireless power transfer system according to the types of the cores found in the system. It is defined as the centre of the inductor as that of the centre of the earth which is very much responsible for the transmission of the different forms of energy within the coil. The coils are of two various types. The primary coil is of soft iron and the second one is of air.

There is presence of several types of physical factors that also affects the overall function of the inductance of the coil. The different types of factors includes the measurement of the coil, the total number of the coil, the nature of the coil used and the total number of layers in the winding of the different coils present in the wireless power transfer system. The twice the number of the coils present in the wireless power transfer system also affects the nature of the electric field produced in the system and it helps in the overall production of twice the current as needed by the system to produce the desired electric field in the coil of the system.

The next factor is the diameter of the coil that also affects the functioning of the power system .There is a requirement of more electric lines of force to counter the overall electromotive force by the use of the large diameter of the coil used in the system. The overall field of the coil maximizes directly as the overall area of the coil increases with the diameter of the coil.

The last factor that affects the inductance in overall length of the coil in the wireless power transfer system. The doubling of the length of the coil in the system while keeping the total number of halves as the same also results in keeping the value of the inductance to half in the wireless power transfer system. It means the overall length of the coil depends directly on the coil present in the wireless powerless system.

The final factor that is involved is the type of the core material that is utilized in the coil of the wireless power transfer system. The inductance of the coil depends directly on the type or nature of the equipment of the core used in the wireless power transfer system.

The underlined factors have an essential role in maintaining the overall shape or the overall nature of the material used in the inductance of the coil. It helps to shape up the whole framework of the inductance system and also helps in the correct dependability of the different factors on the total inductivity of the wireless power transfer system that helps in the maintenance of the correct form of the type of the inductance that is used to depict the correct relationship between the overall structure of the inductance with the different determinants or the different forms of the factors that are present in the coil for the correct functioning of the structure obtained in the maintenance of the structure involving the design of the coil in the self inductance of the coils in the wireless power transfer system.

The factors also help to determine the nature of the inductance of the coils and also help to introduce the important aspects in the determining of the correct form of the structure of the self –inductance in the coil system of the wireless power transfer system. It also helps to inhibit the overall dependency if the different types of the factors on the overall nature of them material used in the system.

Resonance frequency and capacitance

The overall energy of the capacitor exists in the surrounding electrical fields that is proportional to the square of the overall field strength and is total proportional to the different charge plates in the electric field (Ko et al. 2015 ). The reactance of an electrical coil looks like a reactance involved in the parallel direction with the different capacitance (Chen et al .2014). The self- capacitance occurs due to the different adjacent capacitate turns through the different multi layered coils in the electric field.

Resonant circuits

It contains of any system having at least a pair complex type of conjugate poles that contains a natural frequency of the overall oscillation power in the field (Yang et al. 2015). The frequency of the system of the driving force collides with the overall natural frequency produced in the different oscillations hat result in the system being more resonated and the power of the resonated circuit becomes the maximum at that particular point (Harish et al. 2016). The phenomenon is expressed as resonance and the frequency at which the different oscillations of the frequency take place is called resonance frequency.

In the electrical system the phenomenon of resonance occurs in the different systems having one capacitor and one inductor (Ng et al .2014). The nature of the circuit under the resonance is purely resistive in nature.

The electrical resonance is broadly divided in to two categories or divisions:

• Series resonance
• Parallel resonance.

The two categories of the electrical resonance are broadly classified in details in the following:

Series resonance

The different types of circuits containing the resonance, capacitance and inductance elements contain a different type of special chartactersrtics that helps to be useful in the different type of applications as the different types of characteristics of the different frequencies have a sharp maxim mum or minimum frequency points at that particular point in the circuit(Xu et al .2014). In case of the series resonance circuits the overall condition of the resonance is very much straightforward and is also characterstiesd by a number of zero phases and minimum impedance in the different electrical circuits (Ho et al .2014).

Quality factor is determined as the overall measurement of the overall loss occurred in the circuit (Kim et al .2016). The different types of reactive components include or contain the different inductors and capacitors that are often expressed by the figure of merit expressed as Q.

Fig 2.4: Series RLC circuit connected to a voltage source V

Parallel resonance

The different types of the parallel resonance circuit contain the tank circuit that occurs due to the storage of the overall energy in the different inductors and the capacitors of the concerned circuit (Riehl et al. 2015). In the ideal case the overall capacitor absorbs the overall energy during one half life cycle of the overall power curves at the same speed or rate in which it is released by

theinductor.

Fig 2.5 :Parallel RLC circuit connected to a voltage source V.

Equivalent circuit

The different electromagnetic resonance coupling contains the different types of LC resonance and help in the overall transferring of the power with the different electromagnetic coupling waves (Niyato et al. 2016). The electric coupling and the magnetic coupling are expressed as the mutual capacitance and the inductance. The overall power in the circuit is transferred by the use of the magnetic coupling wire (Lee et al. 2014).

Fig 2.6: Relevant Circuit of Power Transfer System.

(Source: Lee et al. 2014)

Ohmic resistance

The total ohmic resistance for an N-turn circular loop antenna with the loop radius a and b is expressed in the following equation:

R = N.a/b

(Source: Colak et al., 2015)

Conclusion

In this chapter the reader has used the different types of modeling method to describe the different types of the different inductance coils and try to depict the relationship between the self inductance methods used in the different types of designs used in the coils and the overall

inductance among two different coils in the study (Colak et al .2015).

Chapter 3

Parametric study of the wireless power transfer systems

The underlined study focuses on the two different models of the wireless power transfer systems using the overall electromagnetic program EMPRO (Na et al. 2015). The foremost model is the single transmitter receiver model (Costanzo et al .21015). The underlined study focuses on the overall turns in the coil, height of the coil, radius of the loop, radius of the coil and the overall angle between the receiver and the transmitter in the study.

Fig 3.1 Structure of single transmitter single receiver

The second model is the two transmitter receiver where there is the study of the effect of the four different parameters and also the overall distance between the loop and the transmitter coils, radius of the transmitter coils, distance between the two transmitter oils and the overall angle between the receiver and the transmitter in the coil (Zeng and Zhnag ,2015).

Fig 3.2 Structure of two transmitter single receiver

Electromagnetic professional program

It is a three dimensional structural full wave electromagnetic solver used in the solving of the different transmission and receiving of the different waves located in the medium (Bosshard and Kolar, 2016). It helps to customize and the organization of the different objects by the use or introduction of different features like the parameterization and the scripting of the different objects. It helps in the overall formation of the different types of projects by using the General user interface principle (Samanta and Rathore, 2015). The program consists of the following features and it helps in the following advantage or benefits in the following areas:

• Parameterized solid modelling structure.
• It also helps in the formation of the modern 3dimensional design environment.
• It helps in the creation of the different choices in the flexibility of the full wave of the different 3 dimensional simulative technologies FEM, FDTD and Eigen mode.

FEM simulation method

It is a process which is used to calculate the overall three dimensional structure of the electromagnetic field inside a structure that is based on the overall fine method used in the underlined process or study. According to Zhu et al. (2016), it helps to provide the critical analysis of the simulation process and the implementation of the EMPRO method in the underlined process that helps to detect the overall S- parameters used in the computation of the simulation in the magnetic and electric fields(Musavi and Eberele, 2014).

Finite Element method

It focuses on the overall action of dividing the overall space of the elements into several different small regions or places that helps to represent or express the field in each of the element present by the different use of the local function (Tang et al. 2018). The implementation style used by the underlined method uses the tetrahedral elements to help in the proper modification or identification of the different circuits in the node.

Size of the Mesh against the accuracy

There is an overall trade off between the accuracy level and the size of the mesh of the total amount of the different available computing resources available by the use of the Finite element method (Atya et al. 2017). The accuracy of the solution is dependent on the total availability or the size of the different elements of the mesh in the model (Fu et al. 2014). The small size of the different elements present in the mesh is not so much accurate as the mesh elements that are very much large or present in bulk quantities.

The tetrahedron elements has to occupy or capture a small part of the field that is adequate enough with the different interpolated values from the different types of nodes present in the field(Barman et al. 2015). The generation of a field solution with a large amount of the presence of the different types of the elements requires a large amount of the computing memory and power available in the field (Lee and Han, 2015). It is very much required to fine the accurate mount of solution that is available for the generation of the correct amount of the available computing power and memory to generate the field solution for the mesh and generate the desired and accurate field solution for the electric field.

The overall production of the optimal mesh requires an FEM type of simulator that is used to produce a mesh which is very much critical defined or simplified in the different types of the available regions (Mi et al. 2016). It exhibits a solution that is based on the coarse mesh and helps in generating the new solution based on the overall availability of the mesh structure available in the field.

Parametric study of the single transmitter server

An in depth analysis of the parametric study of the single transmitter server has been conducted to explore the overall difference in the various essential parameters involved in the overall design of the single transmitted server in a detailed way.

Height of the coil

The height of the coil is depicted in a better or in detailed way by analytically conducting an experiment that helps to inhibit the different values of the height of the coil by the use of the single transmitter server.

Result of S21 parameter at H=20 cm and efficiency 75.69% for single transmitter single receiver.

At H=10 cm, from previous equation L=36.03 μH and from simulation resonant

Frequency equal 8.021 MHz as shown in and the capacitance from equation is expressed as the following table.

 N H(cm) R(cm) L( µH) F(Mhz) C( pF) Ƞ 8 22 40 38.038618 9.0213 9.64332197 76.31% 8 20 40 39.689254 8.8153 9.72998352 72.26% 8 18 40 41.493873 8.5701 10.9269671 68.45% 8 16 40 43.475079 8.2510 10.3540476 64.62% 8 14 40 45.660122 7.0221 10.51401484 58.64% 8 10 40 48.082168 5.6426 11.20528866 54.64% 8 8 40 50.781988 5.2001 12.2502814 50.42%

Fig: Parametric results depicting the various values for H by using the single transmitter single receiver.

(Source: Mi et al., 2016)

It indicates the value of the inductance is decreased with the overall increase in the height of the coil and it also helps to depict that the values of the different inductance are contrarily corresponding to the values of the height of the coil.

Amount of turns in the coil of the system

It is also an important parameter or mode of the overall measurement of the single transmitter single receiver.

Fig: Result of S21 parameter at N=6 cm and efficiency 79.7% for single transmitter single receiver

(Source: Mi et al. 2016)

 N H(cm) R(cm) L( µ H) F(Mhz ) C(pf) Ƞ 10 30 40 63.6222 6.1632 12. 3110798 70.89% 9 30 40 49.6543 7.6832 11.2345678 74.68% 8 30 40 36. 5823 8.5432 11.6543782 78.88% 7 30 40 26.5432 9.6345 10.9876543 77.68% 6 30 40 16.4563 10.688 8.8976543 79.50%

Fig: Parametric results with the various results for N for the single transmitter receiver

It is clearly depicted from the above results in the table that the total number of turns in the coil has a large effect on the number of the capacitance, inductance, resonant frequency and the total efficiency of the single transmitter server.

The radius of the loop also exerts a significant influence on the efficiency of the single transmitter of the server and it has no influence on the other parameters or the determinants like the inductance, capacitance, and resonance of the circuit as it affect the different fields of the coil and not on the various determinants of the coils.

 N H(cm) R(cm) rLoop(mm) L( µ H) F(Hz) C(pf) Ƞ 6 10 20 230 38.87655 8.6821 10.65078 76.84% 6 10 20 240 38.87655 6.9890 10.87654 72.63% 6 10 20 220 38.87655 6.8765 10.98765 68.53% 6 10 20 210 38.87655 6.6756 10.87654 64.63% 6 10 20 190 38.87655 6.4327 10.98132 62.52% 6 10 20 180 38.87655 6.5678 10.87653 56.56% 6 10 20 130 38.87655 6.9876 10.87564 37.65% 6 10 20 100 38.87655 7.8765 10.54378 10.67%

Fig: Parametric results with different values of the radius of the coil r for a single transmitter receiver

(Source: (Mi et al. 2016)

The radius of the coil inhibits a great importance on the capacitance, reverberation density, inductance and the effectiveness of the transmitter of the server.

 N H(cm) R(cm) Rloop(cm) L(μ H) F(MHz) C (pF) Ƞ 6 15 38 26.545002 08 55.098 5.6180 14.580018 04 84.78% 6 15 36 25.217751 98 51.37813 6.1890 13.6543210 82.56% 6 15 34 23.890501 88 47.69608 6.3456 12.7865432 80.67% 6 15 32 22.563251 75 44.056 6.8954 11.5643210 78.65% 6 15 30 21.236001 65 40.46562 6.5643 10.9876543 81.65% 6 15 28 19.908751 55 36.92740 7.9870 10.8765432 76.65% 6 15 26 18.581501 44 33.44875 6.8641 9.87654321 77.98%

Table 3.4 Parametric results with different values of R for single transmitter single receiver.

Optimum coil for single transmitter receiver

The optimum results obtained from the efficiency at 84.65% where N =6, H= 15 cm, r=28 cm and R=40 cm but the disadvantage of the results is that it is of a huge size. In the use of the practical implementation the different types of dimensions used have an efficiency of 80.26% for

N= 6, H= 12cm, r= 25 cm and R =30cm.

 N H(cm) R(cm) r(loop) L( μ H) C(pF) F(MHz) Ƞ 6 15 28 26 36.65333 13.43567 7.8975 87.89% 6 15 28 25 36.65333 13.67890 7.8753 86.87% 6 15 28 25 35.56333 12.76548 6.6789 85.72% 6 15 28 26 35.57333 12.78954 6.8765 82.65% 6 15 28 25 34.56744 11.87653 6.7864 81.76% 6 15 28 26 32.56543 12.87542 7.3564 80.78% 6 15 28 25 32.45676 11.89765 6.8761 80.98%

Table: Results of parametric study with different values for single transmitter single receiver

Angle between the receiver and the transmitter

The effect of the angle between the receiver and the transmitter can be known by the use of the following table.

Table: Efficiency with different angle (Ɵ) for single transmitter single receiver.

Parametric study of two single transmitter receivers

The above results on the underlined table has shown that there has been a problem of the overall coverage area in the entire system that have resulted in the efficiency drop in cases when the concerned receiver is moved by an angle and hence it uses the two transmitter receiver to encounter the following problem in the study. The different variables in the system are the distance between the transmitters and their loop (dl) the radius of the transmitter loop(r) and distance between two transmitters (ds) in the system.

Distance between two transmitters

The overall distance between the two transmitters have a great effect on the efficiency encountered by the system and it has no influence on the other parameters of the machine liker the height of the coil, the loop radious, radius of the system and the angle between the receiver and the transmitter in the system. The above results depict that the bringing of the two transmitters in close relation to each other in the different coils causes a total minimization of the overall efficiency and the separation of the two transmitter coils between each other are far away from each other by a measurement of a total ds= 25mm.

It helps in the total change in the overall efficiency observed in the system and also helps to increase the overall efficiency of the system in a right manner in the two systems in the coils of the wireless power transfer system.

N H(cm) R(cm) F(MHz) R(trans) dl ds Ƞ

6 14 30 8.6781 250mm 60mm 4mm 43.65%

6 14 30 8.9872 250mm 60mm 4mm 46.87%

6 14 30 8.6540 250mm 60mm 4mm 54.78%

6 14 30 8.2137 250mm 60mm 4mm 56.98%

6 14 30 8.0987 250mm 60mm 4mm 50.78%

6 14 30 8.5731 250mm 60mm 4mm 43.78%

Table: Different distance between two transmitters (ds).

Distance between the transmitters and the loop

In order to study the overall difference between the loop and the different transmitters of the models used in the different coils of the wireless power transfer system , the setting up of the dl values starting from the range between dl=10mm to dl=110mm. It depicts that the overall distance between the different loop and the transmitters also has a minimizing effect on the overall efficiency of the system.

Table: Different distance between two transmitters and their loop (dl) for two transmitter single receiver coil.

In order to study the overall effect of t he radius of the transmitter loop in the two systems of the wireless power transfer system the two transmitters are taken at a distance of 25mm and the distance between the transmitters and the loop are set at a distance of about 50 mm depending on the overall minimal value as obtained in the underlined sections of the underlined study. The overall radius of the transmitter loop is set up at a distance of about 190mm to 300mm in the system.

Table: Different radius of the transmitter loop (r) andȠ for two transmitter single receiver system.

Optimum result of the two transmitters single receiver systems

It has been underlined from the following sections that the best efficiency rate for the system is 65.56% which is obtained as N= 5cm, H=150mm, r=300mm, dl=50mm and ds= 25mm. The further development has been made in the parametric study by the use of the optimum efficiency level at an amount of 65.46% obtained at r=280mm, dl=60mm and ds =30mm.

 N H(cm) R(cm) F(MH z) r(trans) dl ds Ƞ 5 15 30 8.6541 280mm 60mm 30mm 67.85% 5 15 30 8.6754 280mm 60mm 30mm 64.45% 5 15 30 8.6431 280mm 60mm 30mm 67.98% 5 15 30 8.0987 280mm 60mm 30mm 61.65% 5 15 30 8.5431 280mm 60mm 30mm 63.78%

Table: Optimization system results with different values for two transmitter single receiver system.

It is depicted from the above table that the overall efficiency of the different transmitters of the different types of the single receiver have a effect on the decrease of the value of the angle from

65.65% to 42.65% as the overall angle of the system has been increased from a range of 0 to 40 degree and increase of the single transmitter model in the wireless power transfer system from an amount of 85 to 30 % as the overall angle has been increased to an o to 40 degrees. The above conclusions helps in analyzing that the efficiency for the mentioned two transmitters single receiver system reduce to about 25% and it drops to 50% for the single transmitter single receiver system for the mentioned increment in the preferred angle system.

Table: Efficiency with different angle (Ɵ) for two transmitter and single receiver system.

Experimental results

In the following chapter, the experiments are carried out to examine the different results in chapter 3 by the correct implementation of the different wireless power transfer models in an experimental way and the comparison with the results obtained in the simulation model.

The two different models used in the experiment are studied in a thorough way to complete the investigation in a successful way. The first model applied in the analysis which is the single transformer single receiver and the second model used in the following experiment is the two transmitters single model in the wireless power transfer system.

In the following experiment there has been an use of the copper wire with a total diameter of 2.80mm and has been wounded around a cylinder which is woody in nature. The total dimension of the coil are N=6, H=170mm and R=360mm as been depicted with the use of the following figure. The signal generator used in the experiment is of the range from 1 to 12 MHz to help in the correct generation of the signal that has been used for the transmitter and the use of the digital oscilloscope is used to calculate the accurate efficiency and measure the received signal from the use of this model.

Single transmitter single receiver experimental results

In the underlined section, there has been use of the two coils in the designing of the wireless power transfer system. The two coils used in the following experiment are one for the use of the receiver and the other for the use of the receiver. The comparison among the acceptor and the transformer used are between 2 meter and the radius of the loops=250 mm as depicted in the underlined figure.

The signal generator used in the experiment of the model has been set up at a voltage amplitude of 20V and the overall frequency of the has been set up to maximum point so that it helps in the successful achievement of the required power transfer at the resonant frequency.It has been found that the frequency at the 10 MHz and is measured at the received voltage at the underlined receiver used in the following experiment.

In the next section the calculation of the efficiency is done at the different angles a shown in the previous figure which also depicts that the increase in the overall angle will result in the decrease of the efficiency of the simulation results.

 Ɵ 0 5 10 20 25 30 35 40 Ƞ 75.68% 74.87% 67.98% 65.32% 45.67% 43.78% 30.78% 20.98%

Table 4.1 Experimental results of efficiency at different angles (Ɵ) for first model.

Two transmitter single receiver experimental results

In this section of the study, there has been the use of three coils one for receiver and two for transmitter with an overall distance between the length of 2 meter and the different receiver coils are of dl = 60 mm, ds=20mm and r = 280 mm. The signal generator frequency is used at an voltage of 20 V which uses the sin wave signal to correctly transmit the signal that has been needed by the resonance frequency of 10 MHz and with the calculated frequency the efficiency has been calculated and it is given as 64.01% at 2 meter distance.

The resonance frequency used for the first model is very much similar to the second model as the two different types of coils are same in terms of wire length, number of turns and the same diameter.

As depicted in the first model, there has been a calculation of the overall efficiency of the two transmitters single receiver model at the different angles which also shows effect and decreases the overall efficiency with the overall increase in the corresponding angle.

 Ɵ 0 15 20 25 35 40 45 Ƞ 63.86% 47.56% 34.68% 31.78% 28.98% 39.87% 33.87%

Table 4.2 : Experimental result of efficiency at different angles (Ɵ) for second model.

Difference between experimental and simulation results

In the following section, there has been strict comparison between the results of the two different model used in the study. The two types of models used are single transmitter single receiver and the two transmitters single receiver of the wireless power transfer system.

Single transmitter single receiver results of the model

It has been found that different simulation results are very much varied from the experimental results as a result of the total imperfection obtained in the overall implementation of the two different coils that has the similar parameters used in the simulation as a result of the ohmic losses in the different conducting coils of the wireless power transfer system.

The highest efficiency at Ɵ=0 in the different results obtained in the simulation experiment is 85.36% as compared to the experimental results of 75.68%. It is about 10 % lower than the different results obtained in the simulation experiments. The resonant frequency in the overall simulation results is 9 MHz and si about 1 MHz than the results obtained in the experimental; results.

 Ɵ) Ƞ(sim) Ƞ(exp) 0 85.38% 75.68% 10 82.68% 73.98% 15 80.89% 65.88% 20 76.56% 62.76% 25 70.98% 54.76% 30 45.76% 37.88% 35 32.65% 16.56%

Table 4.3: Simulation and experimental results of efficiency with different angles (Ɵ) for the first model.

Two transmitters two receiver results of the model comparison results

The second model also follows the same results as in cases of the results obtained in the resonant frequency in the first model. The experimental results are different from the simulation results due to the imperfection in the coils with the similar parameters used in the first model in the above experiment. The highest efficiency at Ɵ=0 in the different simulation results is 65.48% but in the experimental results is 60.78%, which accounts for more than 5 % lower in the simulation results . The resonant frequency in the overall simulation results is 9 MHz and is about 1 MHz than the results obtained in the experimental results in the first model.

The overall efficiency with the angle increment at the overall experimental results of the first model has dropped to about 56% while it also has reduced to 38% in the second model. It is analyzed from the above conclusions that the second model has helped in the depiction of far better conclusion as differentiate to the first model used in the evaluation of the study.

 Ɵ Ƞ(sim) Ƞ(exp) 0 65.45% 63.76% 5 62.78% 56.78% 10 54.76% 50.87% 20 52.87% 48.97% 25 43.78% 40.76% 30 40.68% 38.96%

Table 4.4 : Simulation and experimental results of efficiency with different angles (Ɵ) for the second model.

Conclusions and future work

Conclusion

In the following thesis, the emphasis is given on the designing of a wireless power transfer system at a distance of two meters with the most efficiency. The parametric study for the single transmitter receiver has been conducted to examine the radius of the coil, height of the coil, number of the turns in the coil and the overall angle obtained among the transformer and the acceptor. It has helped to develop the overall efficiency from 76% to 86%.

After the successful conduction of the parametric study carried out on the single transmitter receiver of a wireless power transfer system the experiment have also been conducted on the parametric study on the two transmitters single receiver coli of two wireless power transfer system(Chen et al. 2016). The stud has been carried out on the radius of the coil, height of the coil, number of turns in the coil, radius of the transmitter loop and the angle between the transmitter and the receiver which has also increased the overall efficiency at angle Ɵ= 30 from 40 to 45%.

The different types of simulation results have also been verified with the help of the experimental results which has helped to increase the overall efficiency of more than 15% lower than the simulation results (Ahn and Gindovanlo, 2016). There is overall difference in the reflection and the empirical consequence due to the overall imperfection of producing the different types of coils in the wireless power transfer system.

The two single transmitter receiver models have a more wide coverage area field in comparison to the single transmitter receiver in the coils of the wireless power transfer system. It has been demonstrated by the different analysis and its results by taking in to account the overall efficiency of the angle between the transmitter and receiver of the different types of coils in the wireless power transfer system.

Future work

Based on the above limitations and the final conclusions drawn from the above work, the following research issues and the aspects would help in providing a more natural and progressive scenario to the completed work in the underlined thesis:

The maximum use of the helical wire in the wireless power transfer system to improve the overall efficiency of the two used models in the underlined study.

To provide an in depth analysis of the effect of the misaligned axis between the receiver and transmitter of the two models in the wireless power transfer system.

The repeated use of the parametric study of investigation considering the two transmitter single receiver coil without relying too much on the effect of the result obtained from the first model used in the wireless power transfer system.

The consideration of the more uses of the more than two transmitter receiver coils rather than the use of the single receiver in the wireless power transfer system

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