# PPT_CHAPTER_8
# CHARGERS

#### Slide_1: Battery Charger
A battery charger or recharger is a device used for transferring energy into a secondary cell or rechargeable battery by driving electrical current into it.
* Electric vehicles are equipped with a finite size battery which discharges when driving a certain 8range.
* The chargers used to charge the batteries could be mounted in houses, offices, or in public places.

#### Slide_2:
**AC Charging (Alternating Current)**
* The electric charges flow changes its direction periodically.
* AC is the most commonly used and most preferred electric power for household equipment, office, and buildings, etc.

**DC Charging (Direct Current)**
* The flow of current indirect current does not change periodically. The current flows in a single direction in a steady voltage.
* The major use of DC is to supply power for electrical devices and also to charge batteries. For example, mobile phone batteries, flashlights and electric vehicles.

#### Slide_3: Charging Infrastructure
1. Home Charging
The home private chargers are usually used with a single-phase 230V/15A plug that can produce up to a capacity of about 2.5KW of power.

#### Slide_3.1: Charging Infrastructure(Cont)
2. Public Charging
For charging outside the home premises, EV standards recommends that the electric power needs to be billed and payment needs to be collected.
source:https://upload.wikimedia.org/wikipedia/commons/9/93/Nissan_LEAF_got_thirsty.jpg

#### Slide_4: Charger Working
Charging System Power Flow

#### Slide_5:
**On-Board Chargers and Charging Stations**
source:https://www.researchgate.net/profile/Sebastien_Jacques/publication/316304577/figure/fig1/AS:581657933893632@1515689466152/Typical-EV-on-board-battery-charger-topology-based-on-a-totem-pole-PFC-Soft-start.png

#### Slide_6:
**AC-to-DC**
A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.

source: https://www.electronics-tutorials.ws/wp-content/uploads/2018/05/diode-diode18.gif

source: https://www.youtube.com/watch?v=ACpoRVF4yx0

#### Slide_7:
**DC-to-DC**
source: https://www.youtube.com/watch?v=vwJYIorz_Aw

#### Slide_8: Types of EV Charging Stations
* AC charging Station

* DC charging Station

#### Slide_9: Battery Charging Strategy
* Constant Voltage method
Constant current chargers vary the voltage they apply to the battery to maintain a constant current flow, switching off when the voltage reaches the level of a full charge.

* Constant Current method
Constant current chargers vary the voltage they apply to the battery to maintain a constant current flow, switching off when the voltage reaches the level of a full charge. This design is usually used for nickel-cadmium and nickel-metal hydride cells or batteries.

#### Slide_9.1: Battery Charging Strategy(Cont)
* Constant Current-Constant Voltage method (CC-CV)
CC-CV charging is a usual method to battery charging where the charger applies a constant current until the battery reaches a predefined voltage potential, at which point voltage is kept constant and the current continues to decrease until maximum charging is achieved.
source:https://3.bp.blogspot.com/hhS5OkEyLz0/V0dxDYYBv7I/AAAAAAAAAlE/qrBmDp6rX3E9dBWndDpUMLjSl1hGJXeTQCKgB/s1600/B.png

#### Slide_10: Charging Time
The time required to completely charge a battery pack of a vehicle/system. The time depends on your electric car’s charging point and battery power.

**Factors That Impact Charging Time**
* The type of charger you are using.
* How empty the battery is.
* How long you have been driving.
* The max charging rate of your vehicle and the charger you are using.
* Ambient temperature.
* Charger type.
* Vehicle’s battery size.
* Vehicle’s battery depletion.
* Time of day.

#### Slide_10: Charging Time Calculations

**How to calculate charging time**
1. First calculate your load power (P ) , by multiplying the voltage (U in volts) by the current (I, in amps). You get a value in watts.
P = U x I
For example: 16 A x 230 V = 3,680 W
2. Divide the load power by 1,000 for a value in kilowatts.
For example: 3,680 W = 3.7 kilowatts
3. Divide the power of your battery (also in kW) by the figure obtained to get the charging time.
For example: 24 kW/ 3.7 kW= 6.5 hours