Continental is one of the top five Tier One suppliers in the automotive industry with annual sales of €30.5bn. It invests €1.6bn annually on investigating future trends and technologies and has developed a technology roadmap for integrated powertrain systems.
Franz Lacher, Director of Strategy and Technology, Powertrain Division, says “electrification is necessary to achieve CO2 goals in the future,” adding that more development in energy storage solutions and infrastructure will be required, posing significant technical and economic challenges, particularly on a cost/capacity basis for batteries. But, he continued, “OEMs want to earn money so they must drive down the cost. We know that a consumer will not buy an EV if it costs over €10,000 more than conventional technology.”
Lacher sees the future of powertrain in two main phases, the first being to make the combustion engine more efficient and the second, the ‘roadmap to e-mobility’. “The EU is very demanding,” he says. “75g/km CO2 is already being discussed for 2025.” By 2020, Lacher expects the propulsion split to be 42% gasoline port injected, 27% gasoline direct injection (including boosted and unboosted in both cases) 20% diesel, 8% mild, full and plug-in hybrids and 3% EV (including range extenders).
Neither gasoline nor diesel technology has come close to realising its full potential in reducing CO2 emissions yet, Lacher says. Gasoline engines can be improved by downsizing and improvements in thermal management (12%), two-stage valve lift (5%), cam phasing, direct injection and DCT (5%), stop/start (5%) and the addition of hybrid drives (5%), giving a total potential improvement of 32%.
The diesel roadmap comprises blanket use of common rail (20%), downsizing and compression ratio reduction with further optimisation (10%), stop/start and DCT (4%), improved NOx aftertreatment (4%) and the addition of hybrid electric drives (6%) making a total of 44%.
Lacher sees battery costs dropping by nearly 60% within the next ten years, something that could make a substantial difference to the viability and acceptance of EVs in particular. But he also believes combustion engines will remain the most cost effective solution for the next 20 years and that alternative fuels may one day replace fossil fuels, extending the viability of combustion engines.
The key to developing tomorrow’s powertrain, Lacher says, is “overall system integration and optimisation.” Today the driver takes most of the decisions as to how much engine torque to use and power to apply; in the future, an integrated powertrain system will take more control. “The system will decide what is the best energy source and the best method for deploying it.” Integrated power management systems will in turn be more fully integrated with chassis and safety systems and interior systems to produce a fully integrated energy management system. But, warns Lacher, “I expect a 200kg penalty for this.”
Continental’s contribution to electrification of road vehicles includes the externally excited synchronous motor. Renault already uses the motor and Continental claims to be the only manufacturer mass-producing the technology. Its advantages compared to permanent magnet solutions are lower cost, the absence of expensive rare earth metals and improved electrical efficiency at high revs. The lack of magnets means that when the external circuit is open (switched off), the motor cannot generate electrical energy on the overrun, which Continental believes to be safer.
A prototype has been developed in-house and includes a second generation power electronics including DC/DC converter, which is 30% smaller than the first generation. A new on-board charger is also under development. Designed for EVs and plug-in hybrids, the charger produces 10kW and can charge the prototype EV with its 18 kW/hr battery in under 2.5 hours.
Continental is also developing an HMI-based on a 12.3-inch LCD for EVs, giving full details of battery state and range as well as a satnav-based system for finding the nearest charging station. The powertrain division has also developed the Accelerator Force Feedback Pedap (AFFP), claimed to be the world’s first mass-produced active accelerator pedal. The haptic feedback is programmable and it is possible to vary the force according to remaining battery charge.
Another electronic system expected to make production by around 2016 is the Filling Assistant, a smart phone app which works in conjunction with a piezo-based transmitted integrated into the tyre valve (second generation will be attached to the inner sidewall of the tyre). Filling Assistant acknowledges EU legislation which now makes it illegal to drive with tyres under inflated by 20% or 150kpa and alerts the driver if pressure in either of the tyres is low. The phone displays the pressure status when being filled and the car horn hoots when the tyre is at the correct pressure.
