CES 2018: Continental automates charging of EVs, makes them a mobile power bank
Continental will demonstrate at the Consumer Electronics Show (CES) from January 9 to 12 in Las Vegas two new battery charging systems. Designed for convenience, Continental’s automatic wireless charging system transfers charging power inductively, which would mean that a cable is no longer necessary. This system is accompanied by a new Continental micronavigation solution that allows the vehicle to be positioned precisely over the ground-based charging pad.
The second system from Continental, AllCharge, is designed to use any charging point, whatever the charging rate, type of current, or voltage level. AllCharge also allows the EV to double as a mobile power bank capable of supplying AC power off-board without the need for additional equipment. In this role, the vehicle can reportedly be used to provide power for a range of scenarios, from tailgate parties to powering tradesmen’s equipment on construction sites.
“Continental offers an unrivaled range of charging technologies developed on the basis of our extensive cross-divisional know-how,” said Brian McKay, Director of Powertrain Technology & Innovation Continental North America. “The innovative technologies we are showcasing at CES will make charging an electric vehicle simpler, more convenient, and more efficient. This means that the widely discussed issue of range anxiety will soon become largely irrelevant. Additionally, to bring additional features to the consumer, our AllCharge system gives electric vehicles the added utility to serve as a mobile energy source.”
Inductive charging involves transferring charging power wirelessly from a ground-based charging pad to a receiver pad on the underside of the vehicle. Since it is important to locate the vehicle precisely over the ground pad, Continental has developed a micronavigation solution that uses a magnetic location system to position the vehicle up to 10 times more accurately than a conventional parking assistant could, according to the company. Intelligent magnetic field sensors integrated in the ground pad receive signals from the EV and respond by sending sensor data to the vehicle via the vehicle’s existing wireless communication interface. The location system, which operates in the long-range frequency band, is capable of precisely detecting the ground pad even when it is covered by a layer of snow or leaves. Charging then takes place fully automatically. Continuous safety monitoring is performed throughout the charging process.
Cable-based charging involves the conversion of alternating current (AC) from the grid into direct current (DC) that is used to charge the battery. AC/DC conversion takes place either in the charging station itself (DC charging) or on-board the vehicle (AC charging) with the aid of an on-board charger (OBC). The high setup costs for DC charging stations mean that AC charging stations are currently the most widespread type for everyday use. At the same time, however, growing demand for higher charging rates requires ever larger and more expensive on-board chargers. With the AllCharge system, Continental’s engineers adopted a new approach: Instead of including more charging technology into the car, they turned the electric powertrain itself into a “charger.” This meant adapting the electric motor and the inverter (which is used for converting between DC and AC power) to enable them to support the task of charging, as well. The only extra component involved in this system is a DC/DC converter, which ensures that power always flows to the battery at the optimal voltage level. In the case of AC charging, the current flows from the charging station via the electric motor to the inverter, where it is converted into DC current before being supplied to the battery. In the case of DC charging, the current flows directly through the DC/DC converter to the battery.
The company says that AllCharge therefore serves as a kind of universal pass key that enables drivers to use any cable-based charging station. Also, since AC charging is no longer affected by the limitations of an on-board charger, if appropriate AC infrastructure is available, AllCharge can charge the battery at a rate of up to 43 kW, providing up to 31 mi (50 km) of driving range in just ten minutes of charging time. At the same time, with the new Continental system, it is also possible to use 400-V DC fast-charging stations, which can supply up to 94 mi (151 km) of driving range from ten minutes of charging time. For the same charging duration, premium vehicles with a very large battery can even add up to 190 mi (306 km) to their driving range by connecting to an 800-V DC charging station. This brings the charging time closer to the time it takes to refuel a conventional vehicle. Production start is planned for 2022.
Due to the high capacity of their batteries, EVs can double as a power bank. Typically, before an EV with on-board charger can be used in this way, it would first have to be fitted with a power inverter (to convert the DC current into AC current), at a cost of several thousand euros. In contrast, the AllCharge system already comes with pre-integrated bidirectional capability. In addition, the AC current can be supplied with no upper output limit. The bi-directional capability of the AllCharge system allows the EV to be used as a power source not only in the private sphere but also for tradesmen or mobile service providers, where it offers genuine added utility with the potential to open up new business models. Looking further ahead, this functionality will also make it possible to use electric vehicles as grid-integrated mobile energy stores, enabling them to play a part in the transition to renewable energy.
Watch a video about the technology here: http://videoportal.continental-corporation.com/innovation-technology/quickly-and-easily-recharging-electric-cars.