Rally1 hybrid cars (2022-)

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Originally Posted by 1988senna

So for the video as also mentioned that the boost lenth depend on the lenth of of stage ,The total energy have only 100KW, Is there have the boost difference for each boost by the ECU?

For 4KM stage, each boost have 130 HP,But for 40KM stage ,each boost have only 13 HP to saving more energy for the rest of the stage ??

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Man, please aducate yourself in basic physics. Your questions make no sense whatsoever.

First kW or Hp is NOT a unit of energy. It is a unit of power which is a different thing. Power is a quantity used to describe energy flow per unit of time.

The energy is described by joule or Wh (power multiplied by time). In this case the energy is 3,9 kWh which means that the battery is large enough to give the car 3,9 kW steady power for 1 hour, or 234 kW for one minute. That is of course without any recuperation, i.e. recharging by braking power.

The extra power the WRC system can deliver is 100 kW. Now divide 3,9 kWh by 100 kW and you get that the battery capacity is enough for 2,5 minutes of full boost. For city cruising on the road section it can be likely around 3x more.

But of course the recuperation adds a lot of energy. We don't know what recharging power can be used in WRC cars but a heavy braking produces much higher power than the extra boost, which means that the time spend on braking to recharge the energy is not long.

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Originally Posted by Mirek

Man, please aducate yourself in basic physics. Your questions make no sense whatsoever.

First kW or Hp is NOT a unit of energy. It is a unit of power which is a different thing. Power is a quantity used to describe energy flow per unit of time.

The energy is described by joule or Wh (power multiplied by time). In this case the energy is 3,9 kWh which means that the battery is large enough to give the car 3,9 kW steady power for 1 hour, or 234 kW for one minute. That is of course without any recuperation, i.e. recharging by braking power.

The extra power the WRC system can deliver is 100 kW. Now divide 3,9 kWh by 100 kW and you get that the battery capacity is enough for 2,5 minutes of full boost. For city cruising on the road section it can be likely around 3x more.

But of course the recuperation adds a lot of energy. We don't know what recharging power can be used in WRC cars but a heavy braking produces much higher power than the extra boost, which means that the time spend on braking to recharge the energy is not long.

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thanks for explain .I really misunderstand the kW and the kWh. if it's 80% of the total capacity always .then the really capacity is 3.12kWh right?

I see some artical said the driver can make the regen to let the battery up to 80% during the road section .so that it can be ready for next stage.but if there have not enough length road section or not enough time for regen to back to 80%.what could the driver do

and for the boost time. the 3.9kWh can boost for 2.5 minutes with 100kw .so if there have the long long straight during the stage.will the driver make the boost as long as possible or they will touch the brake to end boost to save the energy

will the team reduce the each boost power less than 100kw(90kw 80kw ) for the long stage like 40km with more long straight stage in Finland

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Originally Posted by 1988senna

thanks for explain .I really misunderstand the kW and the kWh. if it's 80% of the total capacity always .then the really capacity is 3.12kWh right?

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The battery capability goes down with energy use and back up with energy regeneration/recovery through braking.
Energy is measured in joules
Power is a rate of flow measured in Watts, 1 watt = 1 joule/second
(1kw = 1000w, 1kj = 1000j)
Capacity is useful when using time instead of maths with joules - so Kilowatt hours. As in, that battery will offer *kw for 1 hour at *kwh.

This battery:
3.9kwh rated capacity
3900wh
3900j/s for an hour
234,000j/s for a minute
14,040,000j/s for a second
14,040kj energy when full or at capacity

FIA rule of Launch Boost limit of 1000kj is known
100KW rated max power consumption of the propulsion motor
100kj/s
1000kj / 100kj/s = max 10 seconds (as seen noted in various places)
1000kj = max 7.1% battery capacity used at launch

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I see some artical said the driver can make the regen to let the battery up to 80% during the road section .so that it can be ready for next stage.but if there have not enough length road section or not enough time for regen to back to 80%.what could the driver do

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It's part of the fun. No juice, no boost. Have you got a source for that 80%? Has anybody seen the start line state of charge supposedly in the manufacturer's user guide?

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and for the boost time. the 3.9kWh can boost for 2.5 minutes with 100kw .so if there have the long long straight during the stage.will the driver make the boost as long as possible or they will touch the brake to end boost to save the energy

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There are limits set for each stage by the FIA for how much energy can be used in one boost before having to regen, the regen is also a minimum FIA set limit to recover. We don't know what they are yet to have a meaningful answer.

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will the team reduce the each boost power less than 100kw(90kw 80kw ) for the long stage like 40km with more long straight stage in Finland

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No. Energy will be recovered through braking. Have a mooch at this video https://www.youtube.com/watch?v=yhGDYDkrb8M. The torque maps and how the electric motor integrates with the engine is beyond me.

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Originally Posted by WRCStan

The battery capability goes down with energy use and back up with energy regeneration/recovery through braking.
Energy is measured in joules
Power is a rate of flow measured in Watts, 1 watt = 1 joule/second
(1kw = 1000w, 1kj = 1000j)
Capacity is useful when using time instead of maths with joules - so Kilowatt hours. As in, that battery will offer *kw for 1 hour at *kwh.

This battery:
3.9kwh rated capacity
3900wh
3900j/s for an hour
234,000j/s for a minute
14,040,000j/s for a second
14,040kj energy when full or at capacity

FIA rule of Launch Boost limit of 1000kj is known
100KW rated max power consumption of the propulsion motor
100kj/s
1000kj / 100kj/s = max 10 seconds (as seen noted in various places)
1000kj = max 7.1% battery capacity used at launch



It's part of the fun. No juice, no boost. Have you got a source for that 80%? Has anybody seen the start line state of charge supposedly in the manufacturer's user guide?



There are limits set for each stage by the FIA for how much energy can be used in one boost before having to regen, the regen is also a minimum FIA set limit to recover. We don't know what they are yet to have a meaningful answer.



No. Energy will be recovered through braking. Have a mooch at this video https://www.youtube.com/watch?v=yhGDYDkrb8M. The torque maps and how the electric motor integrates with the engine is beyond me.

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thanks for your details explain
so from my understanding the each boost power is the same 100 kw no matter what stage .but the each boost time should be decide by the FIA for different stage (like 6 seconds for short stage and
3 seconds for longer stage unless take the brake earlier ),but I believe each boost time can't be longer than 10 seconds

I guess the ‘less-aero’ rules only apply to the front of the new cars? They all seem to have picnic tables attached to the rear hatch still..

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Originally Posted by RS

I guess the ‘less-aero’ rules only apply to the front of the new cars? They all seem to have picnic tables attached to the rear hatch still..

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But the picnic tables are a complete set now as there's a bench as well.

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Originally Posted by RS

I guess the ‘less-aero’ rules only apply to the front of the new cars? They all seem to have picnic tables attached to the rear hatch still..

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No more diffuser.

and no more vents to extract air from the wheel arches (cd decks) in the rear of wheel arches

Re the regen by braking...

When a driver brakes sufficiently hard does the regen system then activate to slow the car, partially slow the car, or do the brakes & pads still do all the stopping ?

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Originally Posted by denkimi

No more diffuser.

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Sort of... I'd say the awkward rear bumpers are made along an idea like this: "Let's make the best diffuser which doesn't look too much as a diffuser."