Formula E heads to Mexico for the fourth round of the season with Bird and Virgin leading the championships, a new driver in the field. We preview what to look out for in Mexico.
Argentina last season there were 23 gear changes per lap. A gear change takes roughly 0.05 seconds, so over the course of one lap the car spends 1.15 seconds out of gear, with no power being delivered to the wheels under acceleration, and no regen braking when slowing the car down. Eliminate the need for gear changes, and you could save yourself a valuable amount of time.
That´s valuable information sir, thanks!RicME85 wrote:Season 1 all teams had 5 gears.
Season 2 the powertrains were opened up.
NEXTEV and DS Virgin have dual motor, single gear.
Mahindra and Venturi have 4 gears.
Renault have 2 gears.
ABT have 3 gears.
Andretti is using the season 1 powertrain as they had issues with the one they developed for season 2.
Thanks!Tim.Wright wrote:I have a basic knowledge of electric motor fundamentals - so I will have a crack at answering.
It all comes from the way the torque is created in the motor. The torque is more or less proportional to the current in the windings (via the motor torque constant in Nm/Amp) and the current is more or less proportional to voltage applied to the windings. However, of the voltage which arrives from the power supply, not all of it makes its way across the windings because of the back emf of the motor. The back emf is a voltage which is proportional to rotor speed via the back emf constant in V/RPM and subtracts from the supply voltage.
So as the RPM increase, the back emf increases until it completely cancels out the supply voltage and you get zero current therefore zero torque. At the other end of the scale, at zero RPM, you have zero back emf and theoretically the full motor voltage and therefore torque is available.
So the theoretical torque/speed curve is a downward sloping line that starts at the peak torque (coming from having 100% of the supply voltage creating current) down to a point of zero torque at the speed which corresponds to the speed at which the back emf equals the supply voltage.
In practice there is a limit to the maximum current the motor can support which comes down to the thermal capacity of the windings. For this reason the theoretical peak torque can't be reached because the required current would be so high that the stator will weld itself to itself.
So what you see in the end (nicely demonstrated in the tesla plot) is a constant torque (corresponding to the winding rated current) which then drops off at high speed as the emf starts cancelling out your winding voltage.
The FIA Formula E Championship has opened up a tendering process for new chassis and batteries in readiness for season five of the series, which will begin in the autumn of 2018.
Applicants will be made known and presented for selection at the next FIA World Motorsport Council Meeting in June.
Motorsport.com believes that both Renault and DS Citroen could consider tendering for the battery deal to supply the grid from season five onward.
The objective for the new battery tender is for drivers to complete the current race distance without changing cars.
“We will have a look at the tender because of course it might be very interesting for a manufacturer like DS to work on this and to be the supplier for all the teams,” DS Citroen’s Xavier Mestelan told Motorsport.com.
“But we haven’t taken a decision currently on this point. I think the main focus on the future [for the championship] will be on the battery side. It is very interesting for OEM’s to improve the technology for the road car and the race car.”
Williams Advanced Engineering, who currently supply the entire grid with the battery, are developing their award winning product for seasons three and four, and are believed to be working on a tender to continue in to season five and beyond.
“Along with maintaining the batteries during the season we are continually developing and evaluating options to improve and enhance the batteries going forwards,” Paul McNamara, Technical Director of Williams Advanced Engineering, told Motorsport.com.
“We will be working these into the batteries for season three and four. The key areas that have been in focus for us have been the cooling system, the robustness of the cell mountings in the modules to maintain a very low resistance with the high vibration loads that the batteries see and the control system as we learn how the system behaves.
"The cells themselves will also require development to enable to deliver 250kw and the integration of the cells within the overall mechanical, thermal and electrical package will be key.”
From a chassis perspective, the original Formula E car, designated the Spark-Renault SRT_01E, was designed and built by Spark Racing Technologies alongside Dallara back in 2013/14.
The car was designed with a basic architecture in mind, and has so far served its purpose as a package for teams to develop their own powertrains in season two after an initial first ‘spec season’ in 2014/15.
Energy target 54kW for season five
Initial outlooks on introducing fast-track re-generation aspects such as a four-wheel drive accommodated chassis and the introduction of torque vectoring – a method of differing the amount of power going to each wheel - is likely to be held back until after season five in 2018/19.
That is the season when the championship could target moving to one car per driver, instead of utilising the current two.
“We could work on a lot of [technical] points like they did on the WEC but don’t forget that this series is a start-up,” Mestelan told Motorsport.com.
“Before we increase all the aspects of the technology like a 4WD car, bigger battery, more re-gen technology, we must not forget we must be sure that the series will increase in media coverage.
"Nobody will spend a fortune in this series if we do not have ‘cash back’ in media coverage. So we must build the series step by step.”
It is to encourage experimental development something unseen today in F1.mzso wrote:Maybe they should in the direction of an actual battery manufacturer. None of the ones mentioned are...
Why on earth would you do that? No matter what super nano capacitors you they can only reach the capacity of common li-ion batteries. In theory at least. There are no supercapacitors in with that sort energy density so far.autogyro wrote:It is to encourage experimental development something unseen today in F1.mzso wrote:Maybe they should in the direction of an actual battery manufacturer. None of the ones mentioned are...
If I was involved again I would use graphene/metal capacitors rather than batteries anyway.
Capacitors work better in F1 also.
Unfortunately it will be regulations that set development as usual these days.
Fine if you are in to model aeroplanes but no use if you want to build race cars.
He was a Red Bull junior, and then... The internet has enough hearsay to suggest unflattering things were said or implied about the way Red Bull treats junior drivers. Being a Red Bull junior doesn't guarantee anything either, and the emergence of Max Verstappen and Carlos Sainz Jr was rather unfortunate for Frijns in particular.Starscreamer wrote:Again Robin Frijns got points in a old car =D>
Why doesn't have this guy a place in the Formula 1
Frijns may not have used a phrase 'treat like a dog' but it's not a hearsay that he has badmouthed the program for years. Also he was never a Red Bull junior and Verstappen and Sainz Jr. have absolutely nothing to do with it. Antonio Felix da Costa, who was sensational in the second half of 2012 FR3.5 season - the season Frijns won, was the front runner until Kvyat came out of nowhere and snatched the STR seat under his nose the next year. Max only joined the program in the middle of 2014. Sainz Jr. had been there or thereabouts for years but wasn't convincing enough. Without the unexpected vacancy created by Vettel's move he wouldn't have gotten the seat. At least not before this year.Fulcrum wrote:He was a Red Bull junior, and then... The internet has enough hearsay to suggest unflattering things were said or implied about the way Red Bull treats junior drivers. Being a Red Bull junior doesn't guarantee anything either, and the emergence of Max Verstappen and Carlos Sainz Jr was rather unfortunate for Frijns in particular.
