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Today, there are many signs that electromobility will assert itself during the next ten years, including in Germany. In coming to such an assessment, we must not be deceived by the current situation in Germany, as a look at other coun-tries or other parts of the world shows. For example, in Norway, approximately a third of newly registered vehicles are electric – thanks to massive state support. In the Neth-erlands, the corresponding value is still as high as ten per-cent. The other western industrialized nations have barely started, with a share of one percent, and with Germany bringing up the rear at 0.7 percent.

CHINA AND ASIA IN THE FAST LANEBy contrast, the level of activity in Asia and the breathtak-ing speed of the changes taking place there are highly im-pressive. In 2016, 500,000 electric vehicles were registered in China, of which 115,000 were buses. In the field of

electromobility, China wants to present itself as a driver of innovation and world leader. In effect, Asia is characterized by increasing levels of urbanization and, according to UN forecasts, the number of megacities worldwide with more than 10 million inhabitants will grow from 28 in 2015 to 41 in 2030. Most of these will be located in Asia, China and India. The desire for mobility in these countries will not de-cline; at the same time, however, the cities cannot put up with even more vehicle-generated air pollution.Another aspect of electromobility is taxi drones for person-al transport and developments in this field make such solu-tions a realistic vision for the future. The state transport authorities in Dubai (RTA) want to launch regular test op-eration of autonomous air taxis in the fourth quarter of 2017. Interestingly, the German start-up E-Volo has been awarded the contract for this ahead of its Chinese com-petitor. Promoters of an initiative in Switzerland are

E-Mobility Ready for the Mass Market?Trends, Progress and ExperiencesIt has long been impossible to consider electromobility as a separate entity. Instead, it needs to be considered in the con-text of future megatrends. Continuing urbanization, the expansion of renewable energies, automated driving and new business models such as car sharing and shared vehicles will, in the near future, fundamentally change the way we travel. This was the conclusion that could be drawn from the many presentations and discussions on the 4th Vector E-Mobility Engineering Day in Stuttgart on April 27th of this year. Alongside many numbers and facts, it became clear just how suit-able for daily use e-mobility has become. This is demonstrated, in particular, by urban transport companies which are introducing electric bus fleets together with the associated supply networks. However, there is a need for further clarifi-cation at the levels of charging infrastructure, standardization and cyber security.

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all conceivable requirements. These include not only pricing, cost optimization and billing processes but also, and most importantly, the consideration of intelligent grid function-alities. How much energy is currently available and under what conditions? Should the vehicle be charged immedi-ately at the highest possible charging capacity or is it bet-ter to wait for a more economical time? The next version, which is planned for the end of 2018, will include further features, for example inductive charging systems with ra-dio interface, energy feedback into the supply grid and the temporary emergency supply of households, as well as pan-tograph charging with wireless broadband communication.

SUPPORT FOR INDUCTIVE CHARGINGInductive, wireless charging has the potential to signifi-cantly increase the comfort and convenience of electromo-bility. Charging operations start simply without the need to laboriously connect a cable. Alongside ISO/IEC 15118, which covers the field of communication, ISO 61980 defines the infrastructure requirements and ISO 19363 the vehicle-side prerequisites. Despite this, technological challenges per-sist. These range from real-time wireless broadband com-munication through the detailed positioning of the vehicle and the identification of the ideal coil frequency and the geometry and location of the coils, and on to the detection of foreign bodies or living beings in the area of the coil.As yet there is almost no detailed experience to allow us to answer these questions. As a result, it is hard for standard-ization boards to define binding specifications. The STILLE

hoping to set up air corridors for taxi drones above the country’s freeways. Although projects such as this may not be representative of the general situation, they clearly show how far changes to mobility in other countries have come and what direction the trend here in Germany may take in the longer term.

THE COUNTRY NEEDS FAST CHARGING SYSTEMSFurther reductions in battery costs, together with technical innovations such as a 48V drive that is significantly more efficient than the current high-voltage systems, promise to bring about further improvements at the level of vehicle range. Despite this, it is clear that electromobility cannot take hold in the mass market unless there is a nationwide charging infrastructure. In particular, a dense network of charging columns with fast-charging capabilities will cer-tainly be part of the solution. That is why many different vehicle and infrastructure manufacturers are joining forces as part of CharIN e.V. This internationally active associa-tion is driving forward the large-scale implementation of the Combined Charging System (CCS) that supports both AC and DC charging. CCS is being constantly further devel-oped, for example in order to provide higher charging ca-pacities. Starting at a level of 50 kW, the next aim is to achieve 150 kW and, finally, the level of 350 kW. In the quest for standardization, vehicle-to-grid communication as per ISO/IEC 15118 is a central issue. The standard regulates the establishment of bidirectional high-level communication and permits intelligent charging that is intended to cover

Figure 1: Discussions between leading experts from industry and science concerning forward-looking trends, key technologies and current research results in the field of electromobility at the 4th Vector E-Mobility Engineering Day 2017.

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use of the charging infrastructure, the Dutch infrastructure manufacturer Heliox developed charging stations with du-al-connection for the depot. Thanks to a special DC switch mechanism, a bus can connect to the system even while the bus next to it is still being charged.Even though cable-based charging was originally planned for the depot, pantographs are now also being used here. On the one hand, problems were caused by cable breakag-es due to buses driving over trailing cables. On the other, the bus drivers in the depot frequently forgot to connect the charging cable since, as a result of their driving experi-ence, they were used to charging at the press of a button. This meant buses were often left immobile. The uniform operating concept should now ensure that this can no lon-ger happen.

project, which is supported by the German Federal Ministry for Economic Affairs and Energy (BMWi), has the aim of constructing, measuring and evaluating the systems and technologies that are to be agreed on in the standard and making the results available to the various boards. The companies that are taking part in STILLE have an interna-tional presence and most of them actively contribute to standardization. The vehicle manufacturers’ and infra-structure providers’ aim for Germany is to bring an interop-erable infrastructure for inductive charging to the market in 2020.

ELECTRIC BUSES AS FORERUNNERSWhile general progress in the field of electromobility de-pends on many constraints and circumstances and pro-ceeds with the corresponding caution, the decision-makers in niche sectors such as urban transport can act more flex-ibly and swiftly. These are, practically speaking, closed “eco-systems” because the vehicles are all equipped identically with regard to charging technology. Vehicles, batteries and charging systems can therefore be optimally harmonized for the intended area of use. In the case of electric buses, it is necessary to choose be-tween charging the vehicles in the depot (depot charging) and opportunity charging via a pantograph. While over-night depot charging is less spectacular, fast charging at selected stops, such as terminals or interchanges, is worthy of closer examination. When extended, the pantograph on the roof contacts a charging rail in the charging system and charges as much energy as possible in just a short time.A number of urban transport companies in European cities are already running buses of this sort in test operation. The spectrum ranges from two buses in Copenhagen through to a fleet of 43 buses in Eindhoven. Solutions offering 300, 450 or 600 kW are possible for fast charging systems oper-ating at voltages of 600 to 800 V. The 600-kW system achieves an impressive charging current of 1000 A. The sys-tems comply with the ISO/IEC 15118 standard and support both CCS and pantograph charging.The fact that each of these projects faces its own specific challenges means that operators and manufacturers have been able to collect a wide range of different experiences. Eight 18-m articulated buses are on the road in Cologne. Here, the manufacturer has, for the first time, developed charging systems that transform the 10-kV grid supply voltage into the required 800/600 V DC voltage in a single step. In this way, it has been possible to reduce losses by approximately five percent.

EINDHOVEN THE PIONEERThose responsible for the large-scale project in Eindhoven have been able to gather considerable experience. To en-sure that sufficient energy is available for all 43 buses at all times, fast charging equipment has also been installed in the depot. Depending on the situation, low- or high-capac-ity charging is possible here. To permit the uninterrupted

Figure 2: The Vector VC36PLC-24 control unit provides an interface for standardized communication between electrically powered vehi-cles and the charging infrastructure. It is particularly suitable for small series and supports DIN SPEC 70121 and ISO/IEC 15118.

CHARGING CONTROL UNITS AND CYBER SECURITYVehicle and infrastructure manufactures as well as service providers who typically only produce or supply small series do not generally want to have to get to grips with all the details of standardization, charging communications and electronics development themselves. Despite this, they still need to meet the high standards of the automotive indus-try. For them, the best option is to make use of existing solutions with the corresponding embedded software.Vector Informatik has already developed charging control units with CCS type 2 plugs that are ready for series pro-duction and are suitable for urban buses, postal and logis-tics companies and similar users of small pools of electric commercial vehicles. Vector’s charging control unit (Figure 2) supports DIN SPEC 70121 and ISO/IEC 15118. The control pilot signal corresponds to IEC standard 61851. The tried-and-tested Qualcomm QCA7005 chip is used for powerline communication (PLC). For backend communication, the control unit uses a bidirectional HTTPS-based connection. Consequently, the ECU makes use of proven protocols and technologies to ensure the secure transfer of sensitive data. Because both the hardware and the MICROSAR.V2G

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CONCLUSIONSo far, electromobility has played a fairly subdued role in the public consciousness. Despite this, the participants and experts at the Vector E-Mobility Engineering Day all agreed that this situation is the equivalent of the calm before the storm. It is only a question of time before the final technical obstacles are overcome. Standardization work for the nec-essary technological extensions for vehicles and infrastruc-ture is proceeding at full speed.Even small series manufacturers are now able to call on proven technical embedded solutions and existing control units. We shall therefore just have to wait and see how long it takes before we in Germany can look up from our electric cars and see the first autonomous air taxis driving over-head, or whether we will have to travel to Asia to see such a sight.

More information on the E-Mobility solution from Vectorwww.vector.com/e-mobility

Figure 3: The MICROSAR.V2G embedded basic software for smart charging communication in accordance with DIN SPEC 70121 and ISO/IEC 15118.

software (Figure 3) come from Vector Informatik, it is easy to meet customer-specific requirements.Another very important topic in connection with electro-mobility is cyber security, for example during billing pro-cesses at public charging installations. A great deal of spe-cialist knowledge and experience is needed in order to mas-ter the details of establishing secure connections using TLS or the secure exchange of certificate data – in particular the secret private key. That is why it makes sense to opt for external solutions when dealing with embedded systems for charging in accordance with ISO/IEC 15118. Vector In-formatik’s security concept is based, among other things, on a hardware security module (HSM) that optimally pro-tects control units against external access. In contrast to a software-based security concept with secure hardware ex-tension (SHE), this HSM approach permits asymmetric en-cryption. This means that neither party makes use of per-manently installed keys but that both negotiate new keys at runtime on every transaction. This vastly improves secu-rity.

Author Dipl.-Ing. Dirk Großmann is Senior Manager at Vector Informatik, responsible, among other things, for developing the Vector E-Mobility solution.

Translation of a German publication in emobilitytec 03/2017 (August 2017).