Energy management systems (EMS) control the entire flow of energy in the electrified commercial vehicle. With a new EMS software solution, ZF says it provides another attractive proposal for the commercial vehicle market.
Now taking a central role in the electric or electrified driveline, the ZF EMS can control all auxiliary units such as air compressors, steering pumps and thermal management as well as coordinating the energy requirements of the driveline.
ZF says this integrated approach can help make electrically driven commercial vehicles more efficient: Energy consumption per kilometre can be reduced, resulting in a corresponding increase in range as well as a potentially positive influence on the battery’s service life. In addition, there are further advantages for maintenance, diagnosis and reduced battery costs. ZF offers the EMS as an add-on to commercial vehicle electric drive systems already in volume production.
The ZF EMS coordinates the correct start-up and availability and interaction of all components in the vehicle relevant for the flow of energy. This ranges from the battery’s state of charge to the electric drive and all auxiliary units such as the compressor, DC/DC converter and heating.
“Only such an integrative approach makes it possible to further increase the efficiency of electric vehicles,” explains Winfried Gründler, who is responsible for E-Mobility in ZF‘s Commercial Vehicle Technology Division. “This illustrates the strategic importance that software expertise has for our Group strategy: Next Generation Mobility. In this context, by utilising other recognised ZF functions such as ePreVision, we can make the system even more powerful.”
Thanks to the predictive ePreVision function, the software takes the topographical profile of the route into account to coordinate the energy requirements of the consumables. For example, during predictable, long downhill runs, the compressor can operate on recuperated electrical energy.
The EMS can also take over charging management at the depot where there are also advantages to predictive functions: If a vehicle is routed via a long downhill run in the first trip after leaving the depot, the batteries are not fully charged – as this recuperation phase has been predicted and taken into consideration.
Should the charging state of the battery decrease during a long journey, the EMS can lower the energy requirement priority of the auxiliary units to extend the range, according to ZF. Since the EMS continuously checks the functional status of all consumables, it also simplifies diagnostics.
“With our system, we are targeting bus and truck manufacturers unable to develop their own EMS or want to use them differently,” says Gründler. “Fleet owners such as transport authorities also benefit when only one partner assumes overall responsibility for the energy management of a vehicle. Overall, ZF’s EMS supports a faster launch to market of highly efficient all-electric commercial vehicles.”
ZF says manufacturers also benefit from reduced functional integration efforts. Its EMS uses the electric drive control unit and no additional control units are required. ZF software controls the units via CAN bus interfaces. The interaction of the drive and energy management software is perfectly aligned, the company concludes.