Friedrichshafen / Klettwitz (Germany). When it comes to hybridization, automotive manufacturers are primarily concerned with being able to flexibly adapt hybrid versions to the shifting sands of market requirements. And while electromobility is gaining traction, ZF estimates that at least 70 percent of all new passenger cars in 2030 will still have an internal combustion engine. To comply with stringent CO2 thresholds in the future, a substantial number of these vehicles will likely have an electric motor alongside the internal combustion engine. By the end of the next decade, the hybrid drive is predicted to be a fixture in modern cityscapes, either as a modest electrically driven model with 48 volts or as a high-volt model with electric ranges of up to 100 kilometers.
To support this important transition, ZF designed the new generation of its 8-speed automatic transmission as a modular construction system for hybrid transmissions. The basic transmission, which is mechanically identical, can be used with a maximum power between 24 and 160 kilowatts by swapping various electric motors and the corresponding power electronics for hybrid drives – or, depending on market demands, entirely without electric components. With the exception of the accumulator, all electric and electronic components are fully integrated into the transmission housing in order to keep the installation effort in the automotive manufacturer‘s assembly factory to an absolute minimum.
“Nobody can predict the exact market share of hybrid electric vehicles in 2025,“ explains Stephan von Schuckmann, Head of the Car Powertrain Technology division at ZF. “The modular construction system of the new 8-speed automatic transmission helps afford our customers a kind of insurance against market fluctuations.“
Worldwide Application Underway
The new hybrid transmissions from ZF are slated to come to market in 2022 as part of the first volume production vehicles from BMW, followed by other automotive manufacturers. European production at the Saarbrücken, Germany, location will start gradually. In China and the United States, ZF also plans to quickly gear up for production of the new generation 8HP. “The CO2 thresholds will become stricter in all large markets over the next decade,“ predicts von Schuckmann. “The newest generation of the 8-speed automatic transmission can significantly contribute to reducing vehicle emissions that have an impact on the climate.“
ZF relies on a high Real Net Output Ratio for manufacturing hybrid versions of the new transmission system. Accordingly, the electric motors for the 48-volt and high-volt transmission models are both manufactured at ZF plants. The power electronics, which constitute a high share of the total costs, especially for plug-in hybrid transmissions, were also developed entirely in-house. “We aligned ourselves early on with the scenario of a world with more electric drives,“ says von Schuckmann. “This has allowed us to help secure jobs for our employees as shifts in the market occur.“