AC Charging Vs DC Charging | Which One is Better?

AC Charging Vs DC Charging

Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. There are two-types of electric charge: positive and negative (commonly carried by protons and electrons respectively)

Here we are going to discuss AC charging Vs DC charging in this tutorial.

DC Charging

Fast chargers for electric vehicles make use of DC charging; they convert the power before it enters the vehicle. After conversion, the power goes directly into the car battery, bypassing the car’s converter.

A DC installation requires a lot of power from the grid (around 125 A). This makes its costs (production, installation and operation) quite high, resulting in higher tariffs for charging. However, as it usually allows for much faster charging, it is the preferred charging method to quickly recharge during long-distance trips (for cars that support DC charging). This type of chargers is mostly found along highways, rather than at home or business locations.

AC Charging

This is the most common charging method for electric vehicles with a plug. When plugging an electric vehicle into a normal charge point, the power gets converted inside the vehicle, then moves into the car battery. Charging speeds depend on the output power of the chargepoint as well as the convertor’s capabilities to convert the power to DC.

The required power for AC chargers ranges between 16A (3.7 kWh) and 63A (43 kWh).

This charging method is most suitable for parking spots where the car will stay parked for 20 minutes or longer. Due to its lower costs (production, installation and operation) these are the more commonly found chargers. Also, due to these lower costs it is usually much cheaper to charge at AC chargers, making them more popular for general day to day charging.

Why is DC current is used for charging not AC?

AC cannot be stored in batteries because AC changes their polarity up to 50 (When frequency = 50 Hz) or 60 (When frequency = 60 Hz) times in a second. Therefore the battery terminals keep changing Positive (+ve) becomes Negative (-Ve) and vice versa, but the battery cannot change their terminals with the same speed so that’s why we can’t store AC in Batteries.

Also when we connect a battery with AC Supply, then It will charge during positive half cycle and discharge during negative half cycle, because the Positive (+ve) half cycle cancel the Negative (-Ve) half cycle, so the average voltage or current in a complete cycle is Zero. So there is no chance to store AC in the Batteries.