EDITORIAL
Caught out Cold Dear Reader, I still remember pretty well that, on the way to getting a driving licence, warming up the engine in the driving school was a pretty key thing. The dutiful driving teacher went beyond the task of just conveying the traffic rules and mutual consideration and also stressed the need to handle technical equipment carefully. The advice he gave as a rule of thumb was the need to keep the engine at under 2500 rpm for at least 15 min and not to slam the accelerator pedal to the floor. An oil temperature of 80 °C was the minimum requirement to accommodate high loads. Those with just a water temperature indicator in the car were advised to be more patient when on the road – particularly in winter. This was how the key principles of how to handle a combustion engine properly were explained. One main advantage of electric drives is that the average driver need not worry too much about these tips. Things can get rather challenging, however, when you have both drive systems combined in a single plug-in hybrid. I took such a vehicle for a spin recently: a large SUV. With system performance just under 300 kW it feels sporty, even for a vehicle weighing in at over 2 t. I paid little attention to this as my journey began in a tranquil village and led me along small rural and main roads. I clocked up 21.8 km up to the next motorway slip road. And with a fully charged battery on board, all the way was electric powered.
without any preconditioning – and not well timed for the start of a motorway without any speed limit. What now, when a non-technophile vehicle owner trusts too much in the safety of this drive concept to have bothered to ensure warm-up driving for a considerable time? In this case, predictive operating strategies can certainly help detect the ongoing tribological risk when route guidance is activated and start up the combustion engine at an early stage during minor load requirements. Another completely different aspect is the high level of pollutant emissions when a similar scenario is played out under RDE conditions. Here, we need to rethink the way vehicle homologation is performed. The cover story of this issue is dedicated to this very topic. Happy reading! Best wishes,
Dipl.-Journ. (FH) Martin Westerhoff Deputy Editor in Chief
It became interesting on the acceleration lane. The high load requirement is why the combustion engine had to kick in for the first time during the journey. A cold start after driving for more than 15 min,
MTZ worldwide 06|2017
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