Electrification is coming. As countries improve laws and regulations prohibiting internal combustion engines, the debate over whether electric cars are more environmentally friendly than internal combustion engines will become irrelevant. Here’s what you need to know about pure battery electric vehicles.
AC and DC
Let’s start with charging. Electric vehicles can be set by AC slow charging (AC) or DC fast charging (DC). But with either AC or DC charging, the battery input and output are DC. The question is where AC can be converted to DC, either at the charging station or in the car’s converter. Home outlets are AC, but charging stations can be AC or DC. All-electric cars, even hybrids, have a converter called an onboard charger. It converts AC to DC and then charges the battery.
The main difference between AC charging and DC charging for electric vehicles is the charging speed. The converter in a charging station is more prominent in converting AC power faster than an onboard charger. This is similar to mobile devices, such as smartphones, where the charging head can restore AC power.
Charging mode
Next, let’s talk about charging modes. According to the International Electrotechnical Commission (IEC), the IEC 61851 standard specifies four electric vehicle charging modes – modes 1-4.
Mode 1 is the simplest, without any safety devices between the tram and the charging point. We strongly recommend not to charge this way because if the power consumption exceeds the protection limit, the circuit breaker may trip or, worse, a fire may start due to non-compliance with the Electrical Installation Condition Report requirements. Therefore, many countries are ordered to prohibit this mode.
Mode 2 also refers to charging through a household electrical outlet like Mode 1, but it has a control and safety device called an in-cable control and protection device. Plug-in hybrids are typically charged using Mode 2. It supports over-current and over-temperature protection compared to Mode 1. However, the charging capacity is limited to the maximum rating of the outlet, which is 3.7 kW, depending on the country and region.
Mode 3 uses a dedicated charger, often called a charging station (also known as an EV on-board charger), permanently connected to the grid with control and protection features. Charging power is higher than Mode 2, up from 3.7 kW to 43 kW.
In mode 4, the AC to DC conversion occurs at the charging station, which means that this is the only mode that involves DC charging. As mentioned earlier, it has a much higher power output of over 150 kW. There are two prominent charging standards in this mode – CHAdeMO and CCS.
Charging port type
Image from: SETEC POWER
For AC charging, note Type 1 (SAE J1772) and Type 2. Japanese EVs, such as the Nissan Leaf, use Type 1, but most EVs sold in Malaysia (including the Porsche Taycan (and all European plug-in hybrids)) use Type 2. There is also GB/T, but this is unique to China and Tesla’s proprietary connector that supports both AC and DC charging.
DC charging supports CHAdeMO and CCS (Combine Charging System). The latter is an enhanced version of Type 1 and Type 2 ports (CCS Combo 1 and CCS Combo 2) with two additional ports.
On the other hand, CHAdeMO (short for CHArge de MOve) is the official Japanese standard. Unlike CCS, it does not share parts with AC connectors and requires an additional dedicated interface for CHAdeMO. However, CHAdeMO may lose the market because almost all other electric vehicle manufacturers have agreed to the CCS standard.
Single-phase and three-phase
You may have also heard the term “single-phase and three-phase power supplies”. In the simplest terms, without going into the details of a sine wave with peaks and valleys, a three-phase power supply provides a more consistent and stable power source better suited to higher loads. It increases the system’s power density, increasing the charging capacity up to 22 kW (Mode 3). However, electric vehicles will need to be able to accept 22 kW to take advantage of fast charging. If you are unsure weather your property has a single phase or a three phase supply, get an electrical installation condition report done for the property it will help you understand the nature of electrical supply at your property.
Summarize
In summary, there are two types of charging – AC and DC. the four modes (modes 1-4) specified in the IEC 61851 standard further distinguish between AC and DC settings. For AC slow charging, you only need to know about two charging ports – Type 1 and Type 2. DC fast charging supports CHAdeMO and CCS (CCS 1 and CCS 2), essentially enhanced versions of Type 1 and Type 2 ports.