Fast EV Charging

As fast charging and battery technologies continue to evolve and improve in the near future, experts anticipate the charging time to drop even further. - Narendra Badve

As e-mobility increasingly becomes part of daily life, there is a growing need for more efficient charging solutions. Fast electric vehicle (EV) charging stations equipped with powerful DC chargers are currently the answer. DC EV chargers are an attractive choice because they allow much faster charging than the standard AC EV ones that many EV owners have at home. Today, a DC charger with 150 kW, can put a 200 km charge on an EV in around just 15 minutes. As fast charging and battery technologies continue to evolve and improve in the near future, experts anticipate the charging time to drop even further.

The Fast Charging Market

Some key driving forces are shaping and advancing the EV charging market today. One is stricter government regulation of CO2 emissions. The target to achieve zero emissions by 2050 in most major cities worldwide relies in part on greater EV usage and better fast charging infrastructure. Certainly, the high pollution index in cities, detrimental to inhabitants’ health and quality of life, is a motivation to reach this target. Zero or low emission mobility can help stem the prevalence of air pollution related health problems, such as cardiovascular disease and asthma.

The good news: by 2025 over 100 new EVs are set to launch on the market. This step in the direction of improved urban air quality adds pressure to develop and implement the charging infrastructure required to accommodate additional EVs on the road. Finally, as battery manufacturers optimise their cost structures and economies of scale, EV battery costs are decreasing. The result: electric vehicles have never been more attractive to purchase.

DC EV charging designs

Infineon’s expertise, customers’ benefits

With a one-stop shop of high-quality components and solutions, and complete application and technology know-how, Infineon enables its customers to overcome all fast EV charging design challenges. The company’s broad portfolio covers power ranges from kilowatt to megawatt, and includes power semiconductors, microcontrollers, gate drivers and authentication solutions.

The full spectrum of complete EV charger solutions

As a market leader in power electronics, Infineon helps to bring energy-efficient DC fast charging designs to life. Its CoolMOS and CoolSiC MOSFETs are ideal in a wide range of DC EV fast charging designs. Their advantages include high frequency operation, high power density and reduced switching losses, allow you to reach high levels of efficiency in any battery charging system.

Fast DC charger architecture

Typically, a high-power DC charger design converts an incoming 3-phase AC supply, using an AC-DC and DC-DC convertor, to the DC voltage the vehicle being charged requires. A channel for data transfer is also included to provide information about the vehicle and the battery’s charging status. Vehicle information and owner data are covered by one final element: a secure data channel for billing purposes.

The three primary concerns in DC fast charger architecture are how to minimize the cooling effort, deliver high power density, and reduce overall system size. High power density requires forced air cooling, a standard today. However, next generation charging solutions are exploring the potential of liquid cooling solutions. Compact designs must consider higher switching speeds, in the range of 32 to 100 kHz, to reduce the size of magnetic components.

Chargers from 50 kW to 350 kW

Currently, public charging stations provide power of up to 150 kW in a single installation. In a charging park, a medium voltage transformer from 10 kV to 30 kV is a key component. It uses high-power chargers with up to 350 kW output power each. In this arrangement, all chargers can provide full power simultaneously by using non-isolated topology in each charger.

When choosing the ideal power semiconductor, it is important to know the charger’s power level. Ultimately, the selection of suitable devices depends on this factor. Chargers in a power range above 50 kW are commonly built using Infineon’s IGBTs and CoolSiC MOSFETs and diode power modules, such as CoolSiC Easy Module, IGBT EconoPACK and the IGBT EconoDUAL family. With subunits from 50 kW to 100 kW, chargers with power ranges higher than 100 kW are built by stacking the subunits.

Infineon’s high-quality portfolio of power switches seamlessly works with the Rectifier Diode module. All switches need a driver and all drivers need to be controlled. That is why we also offer the best-fit EiceDRIVER as well as XMC and AURIX microcontrollers for fast EV charging designs.