ELECTRIC VEHICLE TWO AND THREE WHEELER CHARGER

EV charging equipment or EV battery chargers, fall into three main categories ranging from 110 V systems up to over 400 V systems. Most EVs come with an onboard “Level 1” charger as a standard feature. The Level 1 charging unit will typically plug into the standard household outlet using 110 V, and offers about 3.3 kW of power to the vehicle. Next is the Level 2 charger which typically offers about 6.6 kW of power and requires 220–240 V. The Level 2 charging unit must be professionally installed but can charge an EV in about half the time of the Level 1 charger. Finally, Level 3 charging units use very high voltage, typically about 480 V but can charge an EV battery in about 10 min. Due to the high voltage and current of the Level 3 chargers, they are not likely to make their way into private homes as a means of charging EVs, but will more likely be used in public charging stations.

EV chargers are classified into three categories: Level 1, Level 2 and direct current (DC) fast charging. One distinction between these three levels is the input voltage, Level 1 uses 110/120 volts, Level 2 uses 208/240 volts and DC fast chargers use between 200 and 600 volts.

DIFFERENT LEVELS OF CHARGING

It is well known that in India and most of the other countries in the world, the electric power supply voltage (AC) is standard 230 V per phase (400 V—line to line) with a frequency of 50 Hz. But in certain countries like the United States, Canada, South Korea, Japan, etc. the supply voltage is 120 V per phase with a frequency of 60 Hz. The voltage and frequency difference in certain parts of the world allows the manufacturers of the EVCS to manufacture them according to the grid requirements of the respective country. There are 4 levels of charging EVs from EVCS viz. Level 1, Level 2, DC Charging and Superchargers. The brief details on different levels of charging are as follows:

Level 1 (on-board charger):

It is applicable only for countries with 120 V, 60 Hz grid systems. The maximum current capacity is 12 A/ 15 A per phase and has a power level from 1.44 to 1.92 kW. It does not apply to India as the nominal voltage range of the Indian grid is 220 to 240 V (a.c., r.m.s) with a frequency of 50 Hz. Charging time is nearly 20 hours. The advantages of Level 1 chargers are low capital cost, low impact on peak demand charges, and the disadvantage is slow charging.

Level 2 (on-board charger):

This type of charging has a voltage of 240 V per phase with a current capacity of 80 A (maximum) and power levels ranging from 19.2 to 22 kW. India is currently using this level of charging and it is considered as slow or normal charging and used in home charging and few as public charging. Charging time is nearly 8 hours. The advantages of Level 2 chargers are faster charging time, and more energy-efficient compared to level 1 chargers, and the disadvantages are costlier than Level 1 chargers, and high impact on peak demand charges.

DC Charging (off-board charger):

This type of charging is through DC voltage ranging from 50 V to 1500 V DC and maximum current capacity ranges from 80 A to 400 A or higher. The power level shall be in the range of 48 to 400 kW or higher. This type of charger is also called DC Fast Chargers (DCFC) and is generally preferred to be used as a public charging station. The charging time is approximately 0.5 hours. This depends upon the battery capacity and its state of charge (SOC) for a given charge power level. The advantages are high charging power, faster charging compared to Level 1 and 2 chargers, and the disadvantages are more expensive, increase load peaks, complexity of standards, additional safety and security requirements, and can cause problems when EVs are operated in cold weather conditions.

Superchargers (off-board charger):

They are also called TESLA superchargers as it applies only to TESLA EV’s manufactured by the company TESLA. The charger is having both versions of voltage levels 120 V, 240 V, or 400 V or higher. Power capacity ranges from 120 kW and up to a level of 250 kW. Superchargers are also called DCFC. The charging time is approximately 0.33 hours. This depends upon the battery capacity and its SOC for a given charge power level. The advantage is the extreme FC (xFC), and the disadvantages are unique design (not common), and only for TESLA EVs.

Level 1 and Level 2 type of charging is only AC power transfer whereas DC charger and superchargers are only DC-based as it is a fast charger having less time to charge the batteries present in EV’s. Sometimes DC charging is called Level 3 chargers and Tesla Superchargers as Level 4.27 And by going up the levels, we can observe the decrease in charging time by an increase in current capacity.