Dynamic Wireless Charging of Electric Vehicles

The use of fossil fuel has led to environmental problems such as air pollution and climate change. The use of electric vehicles (EVs) is regarded as one of the better solutions for reducing the consumption of fossil fuels compared to traditional internal combustion engine vehicles. This is obviously

Project Title

Dynamic Wireless Charging of Electric Vehicles

Project Area of Specialization

Electrical/Electronic Engineering

Project Summary

The use of fossil fuel has led to environmental problems such as air pollution and climate change. The use of electric vehicles (EVs) is regarded as one of the better solutions for reducing the consumption of fossil fuels compared to traditional internal combustion engine vehicles. This is obviously with the proviso that the electrical energy itself is sourced from green and renewable sources, although the use of EVs (and also electric scooters and motor bicycles) in cities can help reduce urban and street pollution wherever the electricity is sourced. However, the EV has not yet been widely accepted by the consumer due to the limitations in current battery technology and grid connection. This affects the range and recharge times.
The power density of current batteries is low, which means the weight of the onboard batteries which are necessary to supply sufficient power is heavy, and the cost of the batteries is high. At the same time, the charging period is long because the charging current has to be limited to increase battery life and efficiency; and for safety reasons. Also, the current from domestic supplies is restricted. Under these conditions, one solution is to charge when driving rather than charging when stationary. This could reduce the amount of battery storage required on a vehicle. This would have to be wireless and automatic. In reality, there would always be a need for on-board storage since it is unrealistic to install power pick-up in all but major road routes. Therefore a combination of energy storage with stationary and moving (on-line) charging or energy sourcing is required. Both of these can be done by hardwire connection (plug-in for stationary and cable contact for on-line such as used by trains and trolleybuses) by wireless presents a more elegant and safer option since there is no heavy-duty contacts and bare terminals to deal with it is the solution that allows the uninterrupted supplied energy to electric vehicles and long endurance mileage, small carrying capacity of on-board batteries and flexible charging methods.
The wireless power transfer can be achieved through different techniques depending on their efficiency and maximum range of transfer.We used MRPT(magnetic resonance power transfer) technique which provides maximum efficiency with optimal distance range. the new method of coil design is used to increase the efficiency and the compensation circuit is implemented to achieve resonance .

Project Objectives

The main objectives for WPT include efficient and cost effective power transmission with minimum amount of losses and to maximize the surface area that receives power output. As the project is designed for dynamic power transmission i.e. for vehicles in motion so a coil of optimum length and measurement must be so designed so that power outreach becomes sufficient. With an estimated power output of 385 W , our main aim is to reach minimum battery size as well.

Project Implementation Method

The alternating current utility power is first rectified and boosted to DC with high-power factor. The DC power is converted to high frequency AC through Zero Voltage Switching (ZVS) which then resonate in primary compensation network and primary coil. The secondary coil receives the high frequency AC power through mutual inductance. The secondary compensation network together with a secondary coil is required to be tuned to have same resonant frequency, in order to maximize transfer efficiency.AC power is then rectified to DC and DC is filtered to get available to charger battery pack.

Fig : Radiative wireless charging system for EV

Experimental setup will be briefly describing how things will be 
   Designing of circuit for achieving high frequency AC
•    Simple bridge rectifier will convert AC supply into DC.
•    Buck convertor to transform high DC into low value DC.
•    Resonant Oscillator (by using technique of ZVS).
•    Receiving coil with high frequency rectification.

  Compensation Network (CN)
 The purpose of CN is to make coupling between two windings maximum as this network will provide the highest resonance frequency and constant current output. The LCC compensation technique is employed in each transmitter coil and receiver coil. the input of each compensation network of the coil is connected in parallel to common resonant inverter through switch To turn off the coils which are not contributing in mutual induction with receiver coil. 

Fig : Compensation Network [18]

  Coil structure
At the transmission side the unipolar(Q) and bipolar(DD) coil is arranged in series to decrease power pulsation phenomenon and power null phenomenon and DD coil is overlapped with Q coil with ferrite (core all having same size to have uniform and better response to the mutual inductance).
                        
Fig : Coils Structure
   Circuit Delivering Power to Vehicle Battery
 As the voltage is induced into secondary now to deliver it to battery again rectifier will be used which will transform AC to DC in addition a filtering component will be also added to make pure DC without any ripples enter battery.Both constant current and constant voltage will be switched as per need by the load system with the help of following circuit

Benefits of the Project

Dynamic wireless power transfer holds a lot of benefits not only in the automobile industry but also in bullet trains , escalators, wheelchairs and miniature mall and golf course carts. Mainly focusing on less to no fuel consumption we aim to introduce a cost efficient mechanism using no fuel and more wireless power consumption,uninterrupted supply and infinite milage to the vehicle.

Technical Details of Final Deliverable

The 384 W prototype using 85kHz operation frequency is constructed. The output voltage is expected to be stable and mutual inductance between the adjacent transmitters to be negligible with output power pulsation within 2% The DWPT would be able to sustain various loads and energy transfer to moving receiver coil with expected efficiency of 90.37%.

Final Deliverable of the Project

HW/SW integrated system

Core Industry

Energy

Other Industries

Transportation , Telecommunication

Core Technology

Others

Other Technologies

Internet of Things (IoT), Clean Tech

Sustainable Development Goals

Affordable and Clean Energy, Industry, Innovation and Infrastructure, Sustainable Cities and Communities

Required Resources

If you need this project, please contact me on contact@adikhanofficial.com