Electric Vehicles, Electrified in Safety Testing

Figure 1. Infographic illustrates car ecosystems and the key components in a car powered by gasoline and electric. Photo credit: afdc.energy.gov and fuelfreedom.org

Looking Inside Ecosystem

As stated earlier, there are many electronics take part in an EV ecosystem. The primary components forming the electric cars including the battery, the motor controller, and inverters. Outside the car, the charging station is equally important. The charging guns are the main interface refueling from charging stations to the batteries that keep the car going.

Most of the driver care the most is the charging time, as this quick refueling behavior inherited from gasoline cars. The dangerous high voltage electricity is the solution. Charging voltages ranging from 230V AC to 400 V AC with a maximum current of 16A to 63A. Direct Current power source delivers higher voltage from 300 to 500 V DC with maximum current up to 350A. With many electrical components interconnect, the safety standards should also be scrutinized.

Safety Standards in Electric Vehicle Ecosystem

There are many safety testing standards applied in the electric vehicle ecosystem. Below are some of the key testing areas and the associated standards for the reader’s references.

• UL2231-1&2 Standard on Safety for Personnel Protection Systems for Electric Vehicle (EV) Supply Circuits: General Requirements. This standard is set to reduce the risk of electrical shock to user from accessible parts, from charging vehicle.
• As the driver is in contact with their car every day. To ensure personal safety, each part needs to pass critical electrical safety tests. Car parts such as the powering system, charging system, cables, and connectors, charging stations, etc. need testing. ISO 6469-1~3 is one of the main standards that govern the protection of persons inside and outside the vehicle from electric shocks. Basic tests performs are the electric withstanding test, insulation resistance test, and potential equalization tests. A similar standard found in China is GB/T 18381.2~3 and ECE R100 in the European Union (EU) regions.
• Electrical charging station separates into three types. Direct Current (DC) charger for fast charging. Alternate Current (AC) charger for standard charging. And the integrated (AC and DC) for more versatile needs in various designed vehicles. IEC 61851 electric vehicle conductive charging system and UL 2202 Standard for Electric Vehicle (EV) Charging System Equipment are the most common standard for charging stations.

Different countries have different standards, and every EV car designed and the electrical component used are also different. Customer needs to get a professional safety testing consultation on this when they are making the procurements.

What and How it Measures

Every standard mentioned is important. A poorly performed test may result in personal danger. One of the strict quality tests performed in the electrical charging connector uses EEC's SE 7441 series. Performing tests includes AC/DC Hipotrs, insulation resistance, and ground bond, etc. Further, as there are many testing points in a connector, bundling up with the 7006 matrix scanner into an automatic testing system optimizes both quality and efficiency. Figure 2 is an illustration on testing system for EV car connectors. Depending on customers’ testing needs, every test requires different systems to meet specific tasks demand. For example, in the charging station, it is often needed a stable and reliable output AC power source generating 30-150kVA output.

Figure 2. EEC automatic testing system for testing EV car connectors, providing efficient, reliable testing and quality results. This system combines SE 7440 series with 7006 matrix scanners.

As the demand for electric vehicles grows rapidly. At the same time, it is still in their early booming stage. Numerous of recent accidents and safety concerns make a pause on consumer purchase willingness. The safety design and complete safety testing of the electric vehicle become a major challenge for the growth of this industry. EEC has been a leader in safety and power testing for over 40 years. It has developed the most suitable safety testing know-how, including charging stations, internal electrical components, and cables, etc. together with the world-class car manufacturers. Electric vehicles will become the mainstream in the nearest future. We look forward to take part of this transition by making a safer world with safety testing.