Charging electric vehicles can be done through various methods like Level 1, Level 2, and DC fast charging. Level 1 uses a standard 120V outlet while Level 2 uses a 240V outlet, providing faster charging. DC fast charging uses direct current to charge over 80 miles of range in 30 minutes. Wireless charging systems allow charging through induction coils in static parking spots or while driving on special roadways. Battery swapping provides an alternative to charging by exchanging depleted batteries for fully charged ones. Vehicle-to-grid technology enables electric vehicles to export stored energy back to the power grid. Battery management systems monitor battery health and safety through functions like temperature regulation, voltage balancing between cells, and protection from overcharging.

1. Charging Infrastructure

2. Method of charging
1) Level 1: 120-volt, alternating current (AC) power.
charging adds about 4 miles of electric range per hour of charging.
2) Level 2: 240 volt Alternating current (AC) power
charging adds about 10 to 20 miles of electric range per hour of charging.

3. DC Fast Charging (DCFC):
1) Converts AC electricity to direct current (DC) and delivers charge to the vehicle
at high power, typically 50 kilowatts (kW) or greater.
2) More than 80 miles of range in about 30 minutes of charging, depending on
battery size and power level

4. Conductive charging

5. Wireless charging

6. Working principle
• Basic principle of wireless charging is same as transformer working principle.
• In wireless charging there are transmitter and receiver.
• 220V 50Hz AC supply is converted into High frequency alternating current and
this high frequency AC is supplied to transmitter coil.
• It creates alternating magnetic field that cuts the receiver coil and causes the
production of AC power output in receiver coil.

7. Cont…
• But the important thing for efficient wireless charging is to maintain the resonance
frequency between transmitter and receiver.
• To maintain the resonant frequencies, compensation networks are added at both
sides.
• Then finally, this AC power at receiver side rectified to DC and fed to the battery
through Battery Management System (BMS).

8. Static Wireless Charging
• As the name indicates, the vehicle gets charged when it remains static.
• So here we could simply park the EV at the parking spot or in garage which is
incorporated with WCS.
• Transmitter is fitted underneath the ground and receiver is arranged in vehicle’s
underneath.
• To charge the vehicle align the transmitter and receiver and leave it for charging.

9. Static Wireless charging
The charging time depends on the
1) AC supply power level
2) Distance between the transmitter & receiver
and their pad sizes.
This SWCS is best to build in areas where EV is
being parked for a certain time interval

10. Dynamic Wireless Charging System (DWCS):
• As the name indicates here vehicle get charged while in motion.
• The power transfers over the air from a stationary transmitter to the receiver coil in a
moving vehicle.
• By using DWCS
• EV's travelling range could be improved with the continuous charging of its battery while
driving on roadways and highways.
• It reduces the need for large energy storage which further reduce the weight of the
vehicle.
• It reduces time of charging.

11. Dynamic charging

12. Pros & Cons
• Pros
• Environment-Friendly
• No need of wire
• More convenient
• Quieter
• Cons
• Expensive
• Lack of Power and Reduced
Range
• Lack of Charging Stations

13. Battery Swapping
• Battery swapping is a new technology that allows electric vehicle (EV)
owners to swap out their dead or dying batteries for fully charged ones
in a matter of minutes.
• The EV battery swap process is simple
• A robotic arm then removes the depleted battery from the vehicle and
replaced it with a fully charged one.

14. Benefits of battery swapping
1) It eliminates range anxiety
2) Swappable battery electric car is much faster than traditional charging
methods like plugging into an outlet or using a public charging station.
3) Battery swapping is a more efficient use of resources, as it allows for
the reuse of batteries rather than discarding them after a single use

15. • There are currently two main methods of battery swapping:
• With the automated method
batteries are swapped out using a robotic arm,
• The manual method requires
the driver to remove the depleted battery from the vehicle and then
install the fully charged one.

16. Drawbacks
Challenges in battery swapping
1) Firstly, the cost of setting up a battery-swapping station is significant.
2) Finally, some EV manufacturers are hesitant to support battery swapping due to
concerns about potential damage to their vehicles’ batteries.

17. Vehicle to Grid (V2G)
• Vehicle-to-grid, or V2G, technology is smart charging tech that allows car
batteries to give back to the power grid. In essence, it treats these high-capacity
batteries as not only tools to power EVs but backup storage cells for the electrical
grid.
• In simple terms, vehicle to grid enables EVs to export their unused battery
capacity back to the grid to fill gaps in renewable energy generation or provide
support during times of peak demand.

18. Benefit of V2G
• V1G is currently the cheaper and more common option for EV
implementation. In contrast to V2G, which is two-directional
• In addition to improving grid stability, EV owners can also generate revenue from
their exported electricity, a factor that can significantly lower ownership costs over
a vehicle’s lifetime.
• On an environmental level, V2G lowers carbon emissions by helping EVs utilize
higher volumes of renewable energy

19. Drawbacks of V2G
• With more frequent charging and discharging, V2G can impact an EV battery’s
lifespan.
• The conversion process of V2G also yields a loss of energy
• V2G functionality requires specialized hardware – primarily in the form of a bi-
directional inverter – in addition to accompanying software.
• V2G integration carries a higher cost for manufacturers

20. Charger Function
• EV charging involves supply of direct current (DC) to the battery pack. As
electricity distribution systems supply alternate current (AC) power, a converter is
required to provide DC power to the battery. Conductive charging can be AC or
DC.
• The design utilizes a rectifier circuit for converting input AC voltage to high-
voltage DC output, and it also has an electromagnetic interference (EMI) filter to
eliminate high-frequency noise from the input power source

21. Power factor

22. Cont
• Beer is active power (kW)—the useful power, or the liquid beer, is the energy that
is doing work. This is the part you want.
• Foam is reactive power (kVAR)—the foam is wasted power or lost power. It’s the
energy being produced that isn't doing any work, such as the production of heat or
vibration.
• The mug is apparent power (kVA)—the mug is the demand power, or the power
being delivered by the utility

23. Cont.

24. Boost convertor for power factor correction
• For improving power factor active power factor correction is necessary.
• Good option available is BOOST POWER FACTOR CORRECTION CIRCUIT.
• It is also known as PFC convertor. PFC convertor nothing but advanced electronic
circuit which make use of some MOFSETS OR IGBT device and improve the
power quality and eliminate harmonics in supply lines
• These PFC Convertor are used with individual power supply may be small or big
in size

25. Cont…
• Other way of improving the power factor is by adding power bank of
capacitor to supply lines
• The number of capacitor in parallel to the load lines are connected. It get
disconnected automatically by switching circuit to maintain the power
factor as decided by the user.
• Preferably the capacitor bank to improve the power factor should near the
load

26. There are two main causes of poor power factor
•Displacement: This occurs when a circuit’s voltage and current waves are out of
phase, usually due to the presence of reactive elements such as inductors or
capacitors
•Distortion: Defined as the alteration of the wave’s original shape, this is usually
caused by nonlinear circuits, such as rectifiers. These nonlinear waves have a lot of
harmonic content, which distorts the voltage in the grid.
•d.

27. Cont..
• Passive power factor correction (PFC): Improves PF by filtering out harmonics
using passive filters. This is typically used in low-power applications, but is not
enough at high power.
• Active power factor correction (PFC): Uses a switching converter to modulate the
distorted wave in order to shape it into a sine wave.
• The only harmonics present in the new signal are at the switching frequency, so
they are easily filtered out. This is considered the best PFC method, but adds
complexity to the design.

28. Battery Management System
• The BMS monitors and manages a battery pack in order to protect it from
damage, prolong its life, and keep the battery operating within its safety
limits.
• These functions are key to efficiency, reliability, and safety.
• A battery management system allows users to monitor individual cells within a
battery pack.

29. Cont…
• As cells work together to release energy to the load, it is crucial to maintain
stability throughout the whole pack.
• BMS monitors and regulates internal operational parameters, i.e. temperature,
voltage and current during charging and discharging of the battery

30. BMS TOPOLOGIES
• 3.1 Centralized
• One single unit of controller circuit require to controller hole BMS
• 3.2 Distributed:
• In distributed type of BMS, each cell required their own control unit
• 3.3 Modular:
• Modular type of BMS, required certain number of controlling units. Each
controller unit is connected to certain number of cells for controlling the circuits.

31. BMS BLOCK DIAGRAM

32. A BMS monitors
• The state of the battery such as:
• Voltage – Total voltage, voltages of individual cells, minimum and maximum cell
voltage, or voltage of periodic taps.
• Temperature –Average temperature, coolant intake temperature, coolant output
temperature, or temperature of individual cells.
• State of charge – Indicate the charge level of the battery.

33. Cont.
• State of health – Shows the remaining capacity of the battery as % of the original
capacity.
• State of safety – the battery is operating under safe mode or not.
• State of power-
• Short circuit protection
• Over current protection
• Overcharging protection
• Fault in connected device

34. CELL BALANCING
• Normally two types of cell balancing are used in BMS.
• Passive cell balancing
In Passive cell balancing, the bypass resistors are used to discharge the excess voltage and
equalize with other cells.
• Active cell balancing
In the active cell balancing the excess charge of one cell transferred to another cell which
has a low charge to equalize them. It uses charge storing capacitors and inductors.

35. Computation & Communication
• Computation of BMS need to be very efficient and accurate. system has to
perform many operations such as data collection, data processing, data analysis
and communication other part of system.
• The BMS has bi – direction type of communications in two different mode of
communication such as Internal communications and external communications.
BMS communication Provide information about health, state of charge along with
much more details for service and maintenance

36. Benefits of using BMS
• Ensure reliable battery operations
• Continuous battery health monitoring to avoid explosion
• Increases the life span of the battery
• Indicates battery level