Whether at home or at a public facility, electric vehicle (EV) charging station installations are poised to offer the same convenience and accessibility as conventional vehicle fueling stations. While the popularity of EVs creates opportunities for OEMs building charging stations, the infrastructure is a tough environment for power supplies. When installed close to a high-power AC main, power supplies may be susceptible to input voltage line transients caused by lightning or other sources of load instability. For this reason, power supplies in EV charging stations require added protection.
The severity of transients can vary, and some devices have different reliability and availability requirements. Therefore, the International Electrotechnical Commission (IEC) established four overvoltage categories (OVC), also known as installation categories. Among them, OVC III applies to equipment in fixed installations such as machinery hardwired to the AC supply. EV charging stations are included in this category, and their power supplies must meet OVC III requirements.
AC-DC Power Supply Essentials for EV Charging Stations
When it's time to select a power supply for your EV charging station, you can create your own power supply or choose an off-the-shelf standard supply. The advantages of an off-the-shelf solution include:
- OVC III compliance. OVC-compliant power supplies with a working voltage up to 300V (nominal) must tolerate up to 4,000V AC transients.
- EMC compliance. Signals from nearby equipment can affect EV charger performance, so power supplies must prevent interference.
- Minimal no load power consumption. Less energy losses during no-load conditions improves efficiency.
- Power density and compact size. Power supplies with higher power density offer excellent efficiency while saving internal space for better heat dissipation.
Look for OVC-III Compliance and EMC Protection
Daburn Electronics' Polytron PFEV family AC-DC power supplies are well-suited for auxiliary converters in outdoor EV battery charging stations and other OVC-III fixed-installation applications. The series comes in versions ranging from 20 to 150 watts and meets OVC III requirements. The modules accept a wide 90-305V AC universal input range and offer various outputs. No-load power consumption is <0.1W. The units also operate over an ambient temperature range of -40 to +85°C for outdoor use — even in extreme weather.
PFEV AC-DC power modules comply with EMC standards without external components or filters and — thanks to their built-in coreless transformer and compact, low on-resistance MOSFET — boast an exceptionally high power density and 90 percent efficiency.
Additional features and advantages include:
- Isolation Class II
- I/O isolation: 4,300V AC
- 5,000-meter altitude
- Meets UL/IEC/EN 62368-1, IEC/EN 61558-1, IEC/EN 61558-2-16 and IEC/EN 60335-1
When selecting a power supply for EV charging station installations, keep in mind the challenges posed by input voltage line transients and other forms of interference. Our AC-DC power supplies offer a variety of protective features and meet OVC-III requirements for fixed-installation applications, as well as EMC standards, in a compact, efficient module.
For more information about PFEV AC-DC power supplies for EV charging applications, visit our product page.