EV Charging Station Types: AC vs. DC

This article explores the different types of electric vehicle (EV) charging stations, focusing on both AC and DC charging. We’ll delve into the characteristics of each type and highlight the key distinctions between them.

AC Charging Stations

AC charging stations deliver alternating current (AC) power to the vehicle’s on-board charger, which then converts it to direct current (DC) to charge the battery. Here’s a breakdown of the AC charging categories:

Image Courtesy: Littelfuse, Inc.

AC charging stations are categorized into the following sub-types:

• AC Level 1: This is the most basic type, using a standard wall socket to deliver AC power to the vehicle’s on-board charger.

  • It includes two modes: Mode 1 and Mode 2. Both use a 120V AC single-phase input.
  • Mode 1: Delivers 250V AC single-phase (16A max) or 480V AC three-phase (16A max).
  • Mode 2: Delivers 250V AC single-phase (32A max) or 480V AC three-phase (32A max).

• AC Level 2: This type is more powerful and delivers AC power from a dedicated electrical supply directly to the vehicle’s on-board charger.

  • It’s permanently connected to the AC supply and includes safety features like a control pilot and shock protection.
  • Input is typically 208 to 240V single-phase AC. Mode 3 falls under this category.
  • Mode 3: Delivers 250V AC single-phase (32A) or 480V AC three-phase (32A).

As seen in the image above, AC charging stations often incorporate overload protection and ESD suppression. Modern stations often use wireless communication, such as NFC, for user access via NFC cards, and communicate with network servers using protocols like OCPP.

DC Charging Stations

DC charging stations, also known as fast chargers, bypass the vehicle’s on-board charger and deliver direct current (DC) power directly to the battery. This allows for much faster charging speeds.

Image Courtesy: Littelfuse, Inc.

Key characteristics of DC charging stations:

• Deliver DC power directly to the battery, bypassing the vehicle’s on-board charger.
• Input: 380V-600V AC, three-phase.
• Output: DC. Mode 4 falls under this category.

For a more detailed visual representation, refer to EV charging level diagrams (AC level-1, level-2, level-3 and DC type).

EV charging stations are designed to provide efficiency, safety, and reliability for users.

EV Charging Station Manufacturers

Some of the key manufacturers in the EV charging station market include:

ABB, Ample, Blink, BP, ChargePoint, Daimler Mercedes Benz, Eaton, Efacec, EVgo, EVBox, G2Mobility, Hyundai, Pacific Gas and Electric, Phihong, Renault, RWE, Schneider Electric, Shell, Siemens, Webasto, and others.