Demand for electrified drives will grow rapidly in the years to come. Even though the euphoria surrounding purely electric vehicles is currently somewhat muted, experts expect hybrid and electric vehicles to increase their global market share from the current level of 4 percent to approximately 20 percent by 2025. Particular focus will be on the burgeoning Chinese automotive market, where an annual volume of 34 million units is forecast for 2025 – more than a quarter of worldwide vehicle sales. Continental, a technological leader in the field of electric mobility, has now developed a new electric drive tailor-made for the Chinese market, and it features an innovative concept –
The electric motor, transmission, and power electronics are combined in a single unit, saving many components. The compact and cost-effective system is scalable and covers all performance levels in the range of roughly 60 to 120 kW. As a result, it can be used in a wide range of vehicles, from plugin hybrids to powerful electric vehicles. Depending on the intended purpose, the drive is available in two motor variants: an asynchronous machine (ASM) and a permanent-magnet synchronous machine (PSM). The new drive system will be displayed to the general public at IAA 2015. “Continental has proved its comprehensive expertise in electrified drives by means of numerous innovations, starting with its first series-production hybrid system in Europe in 2003.
“We have a profound understanding of the different technologies, and can therefore offer the right solution for every vehicle segment and every market. And when we say ‘right,’ we mean a tailor-made technical solution that is suitable for the market and affordable,” comments Dr. Bernd Mahr, Head of the Hybrid Electric Vehicle (HEV) Business Unit, which is part of the Continental Powertrain Division. “Thanks to its compact packaging, our new electric drive is not only lighter, but also more powerful than comparable concepts. This makes it fun to drive, which is an important factor in the acceptance of electric mobility. A favorable cost level adds to the benefits. This is why we are convinced that this electric drive is precisely the right concept for the Chinese market, and will make a significant contribution to the ongoing expansion of electric mobility.”
Basic design from Germany, development and production in China
Continental’s many years of experience in the development and series production of electric final drives have been incorporated in the new drive concept. The basic design was created at the locations in Berlin and Nuremberg (Headquarters of the HEV Business Unit). During the process, the Continental engineers incorporated and built upon many detailed solutions from other concepts. The integration of the transmission and power electronics means that many components such as connectors, cables, and hydraulic connections, could be omitted. Considerable cost savings were achieved as a result, while the weight of the drive was reduced by approximately 15 percent. The specific customer applications are developed at Continental in China, where the new motor is also produced with Chinese suppliers.
Full range: innovative solutions for every motor type
Hybrid and electric vehicles predominantly use three-phase machines. With these machines, the stator generates a rotating magnetic field that sets in motion the rotor. In terms of the method of construction, a distinction is made between asynchronous machines (ASM) and two types of synchronous machines: permanent-magnet synchronous machines (PSM), which have magnets on their rotors, and externally excited synchronous machines (SM), on which the rotor carries electromagnets in the form of excitation winding that is not magnetized until a flow of current is applied.
Which technology is used depends on the application. For example, an asynchronous machine generally serves as a simple belt-driven starter generator. However, if only a small installation space is available and high output is required, the permanent-magnet synchronous machine is the favorite. In the case of the direct-drive motor, all three technologies can in principle be used and make the most of their advantages. For example, the asynchronous machine is suited primarily to smaller electric vehicles due to its simple design. The compact and powerful permanent-magnet synchronous machine is preferred for use in sports and large electric vehicles, as well as in plug-in hybrids. Alternatively, the particularly energy-efficient synchronous machine technology is a good solution for this vehicle segment. It enables control of the rotor magnetization, which can minimize energy losses. Continental is a technological leader in this sophisticated motor concept.”With the new, compact electric drive, we now have innovative solutions in our portfolio for all three motor technologies and can offer competitive tailor-made electrification for every vehicle type and every market,” explains Mahr. “Customers can assemble the best technology and output in accordance with the modular principle. The modular structure of the machine means that only the rotor and length vary depending on requirements.”