2014-2020 Formula One 1.6l V6 turbo engine formula

[Moose]

Monotonically just means always increasing so you could still satisfy that condition using Wayne's method (so long as the spec ecu allowed for it). However I remember a couple years ago (2012/2011?) Red Bull were in trouble for their (I think) pedal maps. From memory their maps satisfied the strict definition of monotonically but the FIA still weren't happy with it.

If the FIA hadn't meant for you to be able to stick weird curves in here they would have said linearly, not monotonically.

[Vortex37]

Re: Traction control.

The traction control systems that we currently see on road cars, and those that were used in the past on F1 cars, are generally closed loop systems. As rightly pointed out, those would be illegal, according to the rules, that we have access to, on the FIA website. I don't even see why we would need such a system with the current PUs. When traction control is mentioned in the context of 2014/15 racing, it has to be something different. The MGU-K is almost certainly a switched reluctance motor, or one of the multiple variations thereof. These require a control circuit which looks at motor speed, voltage and current. This application note from TI, will give enough clues about how to control motor speed. Section 2.1. Or this one from Freescale. All that's needed, is to control the ramp up motor speed, and do a velocity calculation for initial acceleration. The reverse works for deceleration. The same techniques can be applied in generator mode. Motor - Generator control functions are outside the main spec ECU.

[gruntguru]

Still won't amount to traction control if the driveshaft torque is monitored and has a fixed relationship to throttle position.

[CBeck113]

The only way I see to implement a sort of traction control, and I'm pretty sure that this is where certain teams have their avantage, is through the controll of the MGU-K and, more specifically, the brake-by-wire. Yes, the torque is being monitored, but there is also no specification on how the brake balance has to be controlled. By manipulating the balance of the MGU-K vs. the brakes, and by giving the MGU-K a start-up ramp (fixed to the axle speed), you have created a traction control. Yes, this can be monitored, but the regulation of the braking torque from the MGU-K is allowed, so it seems to me that this is the gap for a TC system.

[R_Redding]

Re: Traction control.
The MGU-K is almost certainly a switched reluctance motor

They are almost certainly not..

It takes 6 cables to drive a SRM in an asymmetric bridge converter , each winding being individually driven and seperate... in neither star or delta.

As every photo so far shows MGUKs an Hs being driven by 3 wires , they will be high performance BLDC motors driven in star or delta (Star is usual) by a three leg H bridge. This configuration also has a big advantage when the MGUK-H is generating as the switching modules will provide the synchronous rectification needed.
Rob

[Abarth]

Monotonically just means always increasing so you could still satisfy that condition using Wayne's method (so long as the spec ecu allowed for it). However I remember a couple years ago (2012/2011?) Red Bull were in trouble for their (I think) pedal maps. From memory their maps satisfied the strict definition of monotonically but the FIA still weren't happy with it.

If the FIA hadn't meant for you to be able to stick weird curves in here they would have said linearly, not monotonically.

No. Linear is ... well linear. But monotonically means only that the torque of the engine is never allowd to decrease while torque demant (gas pedal signal) is increasing.
http://en.wikipedia.org/wiki/Monotonic_function

[Abarth]

Traction control would imply that at a given accelerator pedal position the torque would be variable (i.e. decreasing) when the wheel starts to spin.
This is NOT allowed.
In fact, this enforces it further:

5.5.5 At any given accelerator pedal position and above 4,000rpm, the driver torque demand map must not have a gradient of less than – (minus) 0.045Nm/rpm.

It means that if a wheel starts to spin and the engine speed therefore rises suddenly, the torque cannot fall much and indeed emulating a sort of traction control or rather a driving help.

[mrluke]

I dont understand how that can be possible. The engine does not make peak torque at 13,000 rpm, its probably somewhere below 10,500rpm so at some point as the engine goes through the rev range the torque must go down?

Am I missing something?

[Moose]

I dont understand how that can be possible. The engine does not make peak torque at 13,000 rpm, its probably somewhere below 10,500rpm so at some point as the engine goes through the rev range the torque must go down?

Am I missing something?

Torque demand and torque delivered don't necessarily match.

[Vortex37]

Re: Traction control.
The MGU-K is almost certainly a switched reluctance motor

They are almost certainly not..

It takes 6 cables to drive a SRM in an asymmetric bridge converter , each winding being individually driven and seperate... in neither star or delta.

As every photo so far shows MGUKs an Hs being driven by 3 wires , they will be high performance BLDC motors driven in star or delta (Star is usual) by a three leg H bridge. This configuration also has a big advantage when the MGUK-H is generating as the switching modules will provide the synchronous rectification needed.
Rob

No and yes. If you had given the full sentence quote - "or multiple variations thereof." BLDC is also from the same family(AC motors), and though it has DC in the name it is driven by AC signal( trapezoidal like waveform). Yes, I tend to agree with you that from the photos we have seen, it would possibly indicate a BLDC. Being slightly pedantic for the heck of it, a BLDC with three wires going to it, could easily be two phases driven and the third phase winding used as a sensor. In an attempt to make it easy to understand for non electrics folk, I used the example of a reluctance motor to make the general point that speed and torque control is both possible and needed for these type of motors. Won't make that mistake again. However, whilst I type this, I am looking at a PPMT variation of a reluctance motor as a KERS MGU, which is substantially more efficient than a BLDC motor type implementation.

This link might be of more general interest. Other relevant stuff in their index.

[gruntguru]

I dont understand how that can be possible. The engine does not make peak torque at 13,000 rpm, its probably somewhere below 10,500rpm so at some point as the engine goes through the rev range the torque must go down?

Am I missing something?

For any fixed throttle position there will be a torque curve with respect to rpm. At small throttle settings the torque will peak at quite low rpm and fall as rpm rises. At 100% throttle the torque peak is probably around 8,000 - 10,000 rpm.

All this rule does, is limit the rate at which the torque can fall as rpm climbs beyond the torque peak. Without this rule it would be possible to reduce torque drastically beyond a certain rpm, creating a kind of rev limiter where the throttle setting adjusts the rpm limit. By selecting the correct gear and throttle setting for say a 150 km/hr corner, the rpm limit then permits a maximum wheel speed of say 155 km/hr thus limiting the tyre slip to a desired level - ie traction control.

[OO7]

I'm not sure if the following is of help (with regards to pseudo traction control), but I found it very interesting indeed. I believe it was conducted in 2012:

Renault Sport F1 engine engineer David Lamb explains:

“There are essentially two types of pedal map. There’s a conventional one dimensional pedal map, which is basically a representation of a driver’s throttle against the pedal input that is passed across to the engine controller. You can use this to quickly change the feel of the engine to the driver, but it is slightly obsolete now; you might have found it in the sport ten years ago. Some road cars now feature a ‘sporty’ pedal map of exactly this style, with the initial engine response feeling more aggressive to give the impression of it being racier.

The challenges in Formula 1 in terms of throttle mapping are very different from what those car makers face. Since traction control is banned in Formula 1 it’s up to the driver to modulate the throttle. Getting the right amount of engine output to accelerate the car out of the corners without excessive wheel spin (too high slip ratios) is critical for ensuring good lap times while limiting tire wear. To help the drivers, the engineers try to adjust the throttle map to each driver and corner to make it easier for the driver to maximize traction.

“Now when we talk about pedal maps we talk about the torque pedal map, which is a two dimensional map against engine speed and throttle pedal position. For a given pedal position and a given engine speed, you generate an engine torque demand from the driver. It is this demand that gets fed to the engine side of the ECU to deliver the required amount of torque.”

“With driver torque pedal maps, you can have different philosophies. You can have a constant torque map, where regardless of the engine speed you receive the same torque demand for a given throttle pedal position. However, this offers no wheel spin assistance, which can be incorporated with a constant power style pedal map.

“For example, say you’re at 50% pedal on the throttle and at 15,000 RPM, you might get around 200Nm of torque. If you get a bit of wheelspin and the engine speed increases to 16,000 RPM, the torque at the wheels will be reduced as this is a constant power pedal map – power being the product of torque and engine speed. It’s not traction control as it isn’t controlling to a wheel slip target, but instead an open-loop method to try and help wheelspin control. It can be of real benefit when the tires are worn out.”

“You can have an area of constant torque on a pedal map followed by a region of ‘constant power’ decay afterwards. Your torque pedal map could therefore be a mix of this and a constant torque map, depending on the preference of your driver and your car.”

But it isn’t just in the use of the pedal that mapping is important. It is also when the driver is off-throttle that is of almost equal importance.

“The zero percent line is when the driver is completely off the pedal. It is this line that sets the amount of over-run push. This is when the engine continues to turn and produce torque, albeit still slightly negative, under braking. Getting this correct is essential as we use it to reduce rear locking under engine braking. It’s another open-loop system, this time pseudo anti-lock, so as the tires wear out the driver will tend to increase the amount of push during the course of a stint.

“The downsides are that the heat rejection to water and oil will go up, so fluid temperatures will increase, and you’ll also use more fuel to achieve this. It’s quite a pronounced effect: if you plan to use maximum push for the whole race you could end up adding another two kilos to the starting race fuel load.”

There are, of course, limitations that have been placed upon pedal maps so that a version of traction control doesn’t edge its way back into the sport and the FIA is quite strict on how teams use pedal maps, especially on launch procedure. But during the Fridays teams are working incredibly hard to make sure that they hone pedal maps for each corner and for each driver to make sure that they are happy with throttle application and power output.

[Edis]

Sorry to burst a few bubbles here but Mercedes HPP write all the engine map software for the engines, their engineers trackside control and record what map is being used at all times. It has to be that tightly controlled to allow the engines to run for 5 race weekends. With each map they know exactly how much life is being taken out of the engine per kilometer, running in overtake mode with the highest cylinder pressure would kill the engine in a couple of hundred kilometers, every bit of running is put into the damage matrix so they can have a strategy of when to use each engine.
Thats not to say that the teams cant come up with there own usage strategy and HPP will support them with their plans but at they end of the day they are leased from HPP who are fully in control and they have written all the software.
It also doesnt mean that teams dont have different maps but this will only extend to a set of works egine maps and a set of customer maps that are probably a few iterations behind used for everyone else.
The customer teams dont even have access to the HPP dyno's to write any software of their own and the engines go back to Brixworth between races so they cant be run anywhere else.

The differences between PU's are a lot less than 5hp, more like 0.5hp, the engines are earmarked for a car as they are being built and noit selected based on perfromance.

Mercedes probably have different teams working on engine optimization for its different customers. That's how it worked when McLaren was a customer, and only a few people actually knew the relative performance of the engines going to McLaren and the engines going to Mercedes.

As for the power difference between engines, remember that the accuracy high performance dynamometers like AVL's DynoExact is only +-0.1% of full scale. So if the dyno maximum rated torque is 700 Nm it can only give an accuracy of +-0.7 Nm, or 1.2 hp at 12,000 rpm.

Re: Traction control.
The MGU-K is almost certainly a switched reluctance motor

They are almost certainly not..

It takes 6 cables to drive a SRM in an asymmetric bridge converter , each winding being individually driven and seperate... in neither star or delta.

As every photo so far shows MGUKs an Hs being driven by 3 wires , they will be high performance BLDC motors driven in star or delta (Star is usual) by a three leg H bridge. This configuration also has a big advantage when the MGUK-H is generating as the switching modules will provide the synchronous rectification needed.
Rob

KERS motors were permanent magnet synchronous motors (PMSM), MGU-K is most likely of the same type. Since this is a three phase AC motor it has 3 wires.

Bosch Motorsport did offer a KERS system with a BLDC motor though, as a low cost option. That motor was something like twice the weight of their PMSM offering.

PMSM are a popular choice for production cars too, and they are often found in electric and hybrid vehicles; Chevrolet Volt, BMW i3, Mitsubishi iMIEV, Toyota Prius to mention a few. These usually operate at much lower speeds than your would find in F1, and use cheaper silicon-iron in the stator rather than the cobalt-iron alloys I suspect you find in F1.

[R_Redding]

PMSM are a popular choice for production cars too, and they are often found in electric and hybrid vehicles

If you watch the Supercar Superbuild Porsche 918 episode , they show a modern 150Hp BLDC motor being constructed for Porsche by ZF.

https://www.youtube.com/watch?v=2sKgFRMEtPM

at 18mins here..
https://youtube.googleapis.com/v/2sKgFR ... showinfo=0

I like the jig they use to attach the magnets , I have some 1" x 1" disc magnets that will quite happily remove any skin trapped between them when they snap together.

Rob

[langwadt]

Sorry to burst a few bubbles here but Mercedes HPP write all the engine map software for the engines, their engineers trackside control and record what map is being used at all times. It has to be that tightly controlled to allow the engines to run for 5 race weekends. With each map they know exactly how much life is being taken out of the engine per kilometer, running in overtake mode with the highest cylinder pressure would kill the engine in a couple of hundred kilometers, every bit of running is put into the damage matrix so they can have a strategy of when to use each engine.
Thats not to say that the teams cant come up with there own usage strategy and HPP will support them with their plans but at they end of the day they are leased from HPP who are fully in control and they have written all the software.
It also doesnt mean that teams dont have different maps but this will only extend to a set of works egine maps and a set of customer maps that are probably a few iterations behind used for everyone else.
The customer teams dont even have access to the HPP dyno's to write any software of their own and the engines go back to Brixworth between races so they cant be run anywhere else.

The differences between PU's are a lot less than 5hp, more like 0.5hp, the engines are earmarked for a car as they are being built and noit selected based on perfromance.

Mercedes probably have different teams working on engine optimization for its different customers. That's how it worked when McLaren was a customer, and only a few people actually knew the relative performance of the engines going to McLaren and the engines going to Mercedes.

As for the power difference between engines, remember that the accuracy high performance dynamometers like AVL's DynoExact is only +-0.1% of full scale. So if the dyno maximum rated torque is 700 Nm it can only give an accuracy of +-0.7 Nm, or 1.2 hp at 12,000 rpm.

Re: Traction control.
The MGU-K is almost certainly a switched reluctance motor

They are almost certainly not..

It takes 6 cables to drive a SRM in an asymmetric bridge converter , each winding being individually driven and seperate... in neither star or delta.

As every photo so far shows MGUKs an Hs being driven by 3 wires , they will be high performance BLDC motors driven in star or delta (Star is usual) by a three leg H bridge. This configuration also has a big advantage when the MGUK-H is generating as the switching modules will provide the synchronous rectification needed.
Rob

KERS motors were permanent magnet synchronous motors (PMSM), MGU-K is most likely of the same type. Since this is a three phase AC motor it has 3 wires.

Bosch Motorsport did offer a KERS system with a BLDC motor though, as a low cost option. That motor was something like twice the weight of their PMSM offering.

PMSM are a popular choice for production cars too, and they are often found in electric and hybrid vehicles; Chevrolet Volt, BMW i3, Mitsubishi iMIEV, Toyota Prius to mention a few. These usually operate at much lower speeds than your would find in F1, and use cheaper silicon-iron in the stator rather than the cobalt-iron alloys I suspect you find in F1.

BLDC and PMSM is basically the same thing. Permanent magnet rotor and a three phase stator
Generally a BLDC will be wound to have a trapezoidal bemf so it can be driven with s simpler waveform, but it's not
always the case