The Bright Spark Reports from rome
At the start of the 2020/21 ABB FIA Formula E World Championship season, we revealed our all-new ZF powertrain for use in the M7Electro. But how exactly does this ZF powertrain work? And just how well did it perform on the streets of Rome? There’s only one way to answer this question… cue our resident Bright Spark!
The Bright Spark says…
The ZF powertrain works by transforming DC voltage into AC voltage which brings the motor to life and, depending on the voltage, we accelerate or decelerate the electric motor with high dynamic response. The torque and the wheel speed are changed accordingly via a gear ratio between motor and wheels. For example, Gear ratio 10 means that a torque from the electric motor of 100Nm results in a torque of 1000Nm on the wheels.
This year’s powertrain was designed using the lessons learnt from our powertrain in Season 5. We lost a lot of weight on the package. We implemented new software functionalities too, and all these changes brought us more efficiency. The system has been thermally unlimited so far, and we reduced the losses wherever we could. It is a continuous improvement process.
Coming in to Rome, we were aware the track was very bumpy, that can cause the car tyres to leave the ground completely when at speed. For us it was crucial that the interaction between the driving strategy and the machine control worked well.
When the tyres return to the track after a period in the air there is immediate deceleration, which means that our current controller has to work hard to be able to compensate these dynamic changes. This can cause an issue if not controlled properly – and from which some of our competitors suffered at the weekend. We also knew that Rome’s new layout is a very fast circuit – so we adjusted our derating parameters to ensure that we could provide the top speed required on the cars.
In a race everything has to fit together: the control, the setup, energy management, calibration and also the driver’s condition and self-confidence. We are delighted that in Rome the powertrain worked very well, with the new functions working well on both cars.
Mahindra Racing had been waiting for a podium for two years and this weekend’s success was a big achievement for the whole team.