Resources

Towards the next generation of electric vehicles

19 Jun 2019

Electric vehicles (EVs) have made huge strides in reliability and durability since they were first introduced, and sales figures from across Europe show they’re more popular than ever before. Yet some drivers are still wary of moving from a vehicle powered by fossil fuel to an EV because of “range anxiety” – fear that the car’s battery could run out of charge, and that the existing network of charging stations is not sufficient to allay this concern.

Manufacturers and policymakers both know that assuaging this fear is an integral element to making EVs ever more common on our roads, thereby contributing to lower carbon emissions and tackling climate change. Enhancing the charging infrastructure is just one part of this approach; indeed, enabling motorists to connect their vehicles to the grid at home, and to accelerate the home charging process, are significant aspects of the overall effort to make driving EVs as seamless as possible.

Constant striving for technological advances is also gradually eroding scepticism. For example, the EU project Drivemode aims to develop a highly efficient and compact modular drivetrain for EVs that deploys the vehicle’s battery energy more effectively and optimises the drivetrain design to create a more integrated system, delivering stronger performance and reliability.

The pioneering project brings together the various components of the EV – motor, gearbox and inverter – into a single frame. This model can be adapted and fitted in all types of mass-produced electric and hybrid cars, from high-performance to light duty vehicles and everything in between.

Alexander Smirnov, a research scientist at VTT in Finland, which leads the consortium, explains that one of the major goals of the research is to make the drivetrain as compact as possible. “By reducing the weight, we can increase the running distance of the vehicle, and the way that we have attacked that problem in the project is that we are augmenting the speed of the electric motor. So by increasing the speed we can proportionately decrease the size of the e-motor”, he says.

This is achieved by the deployment of a high-voltage (600-900V) battery that bring the engine’s weight down by reducing the amount of copper needed. The drivetrain therefore augments by 50 per cent the maximum operating speed, leading to a 30 per cent increase in torque but reducing by half motor losses and charging times. It’s the kind of performance reassurance that many motorists keen to switch to EVs have been waiting for.

Jens Muller, manager at German company Semikron, which is working on the inverter, explains that the project has innovated through the refinement of high-performance materials: “We have silicon carbide as an electronic material for the switches, then we have copper for better thermal performance, silicon nitrite ceramics, but also very high performance thermal pastes, any by combining all of those and also design for high thermal performance we get this high power”.

Michael Burghart, senior project leader of AVL, a German company specialised in developing and testing electric drivetrains, adds: “Not only do the supplier and invertor of e-machines have to show over and over again that this drive will be the future, one of the main concerns is to use the resources of the planet in the best possible way. Therefore, it is always a headache to decide whether to use rare earth materials or whether to go with squirrel-cage rotor solutions.”

The Drivemode project has now reached a critical point. The consortium has devised a way of integrating a high-speed gearbox (reaching 97 per cent efficiency around nominal points), a high-speed motor (75 kW, 100 Nm, more than 20,000 rpm) and a silicon carbide inverter (20 kHz switching, 140A rms current) into a high-performance and cost-effective drivetrain module. These main elements are merged with a high-voltage battery, controls and a cooling unit to establish a solid foundation for the next generation of EVs, from buses to racing cars.

Major auto manufacturers such as Audi, Volkswagen and Jaguar have showed interest in the project. The inverter, motor and gearbox will be tested separately, says Alexander Smirnov, and then the components will be assembled into the single frame, to provide the final product of the project. By 2020, “this frame, or this single unit, will be tested by itself, and finally demonstrated in the special demonstration vehicle” he concludes.

A first opportunity to present and review the results of the tests will come at the Coiltech conference in Pordenone, in the north of Italy, where motors and transformer producers from 46 nations will gather in September 2019.

By Margherita Sforza

Photo credits: Michael Mroczek

19 June 2019

On the way to spur uptake of electric and hybrid mobility

4 Jun 2019

DRIVEMODE is a project aimed at developing a distributed and integrated drivetrain module (IDM), scalable to all types of mass produced electric and hybrid cars, from light and C & D passenger vehicles, to high performance and light duty vehicles.

The project partners have reached a critical point in their research; they have devised a way of integrating a high-speed gearbox (reaching 97% efficiency around nominal points), high-speed motor (75 kW, 100 Nm, more than 20,000 rpm) and SiC inverter (20 kHz switching, 140A rms current) into efficient and cost-effective drivetrain modules for distributed drive. The integrated module’s main advantages come from reduced use of materials, simplified OEM installation and optimal synergy between components. In addition the distributed drivetrain concept opens the doors for a single design to serve a variety of vehicles, with improved layout flexibility, control and functionalities.

DRIVEMODE partners met in Nuremberg and Brussels in May 2019 to share the results of each component’s design features and to take the project to the next level – manufacturing. The aim here is to achieve 30% increase in specific torque and power, 50% increase in e-motor speed, high voltage (800 V) for material reduction and fast charging and 50% reduction in losses.

To share knowledge and obtain expert insights, DRIVEMODE partners organise joint events and workshops with similar GV-04 projects (ModulED and ReFreeDrive).

Learn more about DRIVEMODE integrated drivetrain module and its components by visiting the resources openly available on the project website.

Electric cars: current trends make for a shocking change

7 May 2019

Electric cars are rapidly moving from the periphery of the automotive sector in the European Union to the mainstream. The sales figures alone across Europe do not necessarily justify such a bold claim, given that within the overall market, fully-electric vehicles (known as BEVs, or battery-electric vehicles) account for around 1.7 per cent of all passenger vehicles sold. But as the EU looks towards a carbon-neutral future based on green energy and zero emissions, BEVs are undoubtedly integral to the debate around Europe’s automotive future.

While that figure of 1.7 per cent may appear irrelevant, the 21,000 BEVs sold across the EU in January 2019 represent a year-on-year increase of 67 per cent, according to a report by CleanTechnica.com. Fully-electric vehicles are also surging ahead of plug-in hybrids in popularity, with figures from the same month showing that BEVs now account for almost two-thirds of all plug-in vehicles sold in the EU.

With various national incentive schemes promoting the acquisition of zero-emissions vehicles, consumers can make informed choices about the economic advantages of going all-electric. However, support from the EU, through an integrated policy framework across transport, the environment, infrastructure and regional policy, will be essential if electric vehicles are to continue their impressive growth in the market.

Giuseppe Fabri from the Department of Industrial and Information and Engineering and Economics at the University of L’Aquila in Italy, says that the future of passenger transport is inevitably fully electric: “The trend is to design fully electric cars, no longer hybrids that are still tied to fossil fuels. Many car manufacturers are thinking of producing cars in the next five-seven years that are fully electric.”

“But the main problem today is the charging infrastructure, because if you want to go today between Rome and Milan with an electric car it’s not possible. You have to stop after 300 km to recharge the car.” He adds: “In parallel with research, we need to invest in infrastructure and create fast charging systems in cities, as Norway and the Scandinavian countries are doing today.”

In fact, a study by Transport & Environment points out the disparity between northern and western Europe, where charging infrastructure is more sophisticated and more widely available than in southern and eastern Europe.

A pan-European network of charging points for BEVs is taking shape, with around five vehicles on the road for every public charging station, but the study also suggests that only five per cent of vehicle charging takes place at such points, with most charging happening privately, in people’s homes or workplaces.

The urgent need to address the dangers and consequences of climate change is a principal driver of change and innovation in the electric vehicle sector. The EU has set an ambitious target to reduce CO₂ emissions from transport by 60 per cent by 2050 compared to 1990 levels. The regulatory framework at European level is designed to ensure a progressive, steady and predictable transition towards a future in which electric vehicles predominate.

EU member states are reinforcing this trend with their own policies: Sweden, the Netherlands, Ireland, France and Denmark have all pledged to ban sales of new petrol- and diesel-powered vehicles by 2030, and in France all cars powered by internal combustion engines will be banned from the roads by 2040. Regions and cities across Europe are also taking initiatives where they have the power to do so, with Brussels itself introducing rules banning diesel-powered cars from circulating after 2030.

Car manufacturers are investing in developing new electric cars, but the EU is supporting this innovation, funding 165 related projects since 2009. More recently, the European Green Vehicles Initiative is tackling the challenge of decarbonisation of road transport, and contributing to the transition to greener road transport, while boosting the competitiveness of the European economy.

Ultimately, electric cars are going to be successful if they appeal to the consumer from a visual and performance point of view. And manufacturers are only going to develop such a broad range of vehicles if they know these vehicles have the technical reliability to deliver.

In this context, the EU project DriveMode is developing the next-generation of electric drivetrains to suit different types of electric and hybrid cars. Jens Müller, research and development manager of Semikron, is part of the consortium. He told us that through the kind of technological innovation being pioneered by the project, manufacturers will have more options at their disposal to respond to consumers’ varying expectations, fostering choice in the e-vehicle market by widening the technical possibilities as much as possible.

The company is very active in the Chinese market, Mr Müller said. “We have a comparable project that is running in 50,000 units, mainly light buses in China, and we think that the European and also non-European markets will strongly benefit from technologies such as the one developed under DriveMode”.

Furthermore, Lucie Beaumel, of the European Green Vehicle Association, explains that “currently, EU research projects are not only contributing to develop prototypes, but also to improving the techniques of electric car and plug-in hybrid production, so the effect of innovation is multiplied.” Researchers and representatives from the car manufacturers will gather in Brussels in December 2019 at a conference organised by the Association to discuss innovations ways to shape European policy on improving road transport.

By Margherita Sforza

Photo credits: MikesPhotos on Pixabay

7 May 2019

Pushing design and manufacturing of electric and hybrid drivetrains to the next level

22 Oct 2018

These range from light and C & D passenger vehicles to high performance and light duty vehicles. With modularity and scalability being the core concepts behind this innovative project, DRIVEMODE will change the paradigm in electric and hybrid mobility and spur the market uptake of a compact frame composed of a high-speed gearbox, high-speed motor and SiC inverter. This integrated set-up will be mass produced with ease and will be deemed useful in different market segments.

The innovation partners gathered together for a two-day technical meeting in Ljubljana on mid-June 2018. They discussed about the project’s early achievements and fixed the module’s configuration while accounting for the most efficient combination of the components. Plenary sessions were distributed evenly with closed sessions dedicated to specific issues tackled by a few of DRIVEMODE’s technical partners.

The research output on the preliminary design of the drivetrain module were presented by Chalmers and all partners. They highlighted the optimal modularity for the system to fit different car classes. Two design concepts of the electrical motor (Permanent Magnet Synchronous machine and Inductions Asynchronous machine), two transmission concepts and two gear ratios (14.1:1 and 15.9:1) have been examined with the goal of finding the optimal configuration that meets the expected impacts in terms of energy efficiency, compactness and novelty of the module. All components will be joined together with a cooling unit to form a compact frame.

The DRIVEMODE concept will be tested and validated using a demonstration vehicle that will run on a flat road with a top speed of up to 180km/h.

To foster knowledge sharing, the project is already implementing joint activities together with like-minded GV-04 projects, to raise the different stakeholder communities’ awareness about DRIVEMODE’s innovative aspects.

The meeting has been crucial to set the pathway in identifying the components’ configuration, which will ensure DRIVEMODE in meeting the expected impacts and objectives.