Hybrid World Rally Cars

[Rally Power]

Just let's hope rally sport will survive it.

Aaaaaamen!

[AndyRAC]

...and I don't believe WRC is the sport to drive down the cost and make the technology more readily available and more efficient at its purpose through competition by the manufacturers. I think WEC is doing it right by allowing different concepts. Maybe the hybridisation of rally cars will have to wait quite a few more years

A few years ago I thought hybrids should be in the WRC - no longer though. Leave all the 'road relevance' type technology to the WEC: which does it so much better.

[OldF]

You forgot to say that we talk about electric car to be ecological but how do we take that electric energy? Most from carbon, gas, oil etc...

+10 That’s the key issue what is ecological or not.

Less resistance in the water means it will travel through the water rather than through that of more resistance (I.e. A human)

That doesn’t mean that all the current will go true the water. Considering water and a human body two different resistors, they are connected in parallel. Googling for some “facts”:

https://en.wikipedia.org/wiki/Electric_shock

Body resistance[edit]
The voltage necessary for electrocution depends on the current through the body and the duration of the current. Ohm's law states that the current drawn depends on the resistance of the body. The resistance of human skin varies from person to person and fluctuates between different times of day. The NIOSH states "Under dry conditions, the resistance offered by the human body may be as high as 100,000 Ohms. Wet or broken skin may drop the body's resistance to 1,000 Ohms," adding that "high-voltage electrical energy quickly breaks down human skin, reducing the human body's resistance to 500 Ohms."[15]

https://en.wikipedia.org/wiki/Water_resistance

the electrical resistivity of water (0.2 Ω·m sea water, 2 to 200 Ω·m drinking water, 18000 Ω·m deionized water at 20°C)

If a dry human body has a resistance of 100 000 ohm and the water has 2 ohm and both connected in parallel with a voltage of 600 V, the current true the water would be 300,000 A (assuming no fuse blown) and true the body 0,006 A = 6 mA (total current = 300,006 A)

If the resistance of the skin is broken and the resistance will decrease to 1000 ohm the result will be:
True water = 300 A
True body = 0,6 A = 600 mA which would be lethal.

Total current = 300,6 A

Some facts about voltage & current: true a human body.

http://sprott.physics.wisc.edu/demobook/chapter4.htm

Average Effects of Continuous ac or dc Electrical Currents on Healthy Adults

Electrical Current Biological Effect
1 mA threshold for feeling
10-20 mA voluntary let-go of circuit impossible
25 mA onset of muscular contractions
50-200 mA ventricular fibrillation or cardiac arrest

And from a Finnish web site http://www.epanorama.net/faq/sfnet.h...hkoverkko.html

Mitä erisuuruiset ihmiskehon läpi kulkevat virrat vaikuttavat? (How does different amount of current through the human body affect?)

From and above 50mA. Dangerous threshold. The current will affect the heart. If the current affects longer than 0,5 sec, it will cause a heart-stopping or ventricular fibrillation.

From 80 mA and above. Lethal.

As can been seen it’s not all about the voltage but how much current goes true the human body and also about the route true the body (true the heart or not).

Also the resistance of a human body is dependent off the voltage and it will decrease if the voltage increase. With 230 V voltage the resistance is about 11,7 kohm from hand to hand and about 1 k ohm from hand to leg. Also the durability of the shock is vital.

And don’t ever never disconnect the green-yellow wire. It’s not there for fun.

[itix]

You have to remember that they are not in fact connected in parallel unless the battery pack is submerged and some idiot breaks into the car, opens the cover, and touches both the poles (plus and minus).

That is extremely unlikely. In a real situation where the battery pack or an MGU connected to the battery pack gets shorted by water (which already is unlikely), the connection is going to be water to human to water in parallel with water only and water to body shell to water (very much preferred by electricity) and water to earth to water... So human is about the last thing the battery pack will go through.

Also the voltage over human won't be 600v or 800v or whatever, as much of the current will pass through the water.

Voltage over human would be too small to even be felt (or probably even measured). If you put a volt meter across two points in water that you have shorted with high voltage you are going to get a very small voltage (if even detectable if you have a larger amount of water) as you can in theory see the water as veeeery many resistors in series and the voltage will distribute across them. If you measure between the terminals you are going to get 800v but across two points in the water, just a few micro volt (if even that).

If you ever witness a generator overload test, you can try this if you like. It is done by lowering all three phases into the water and shorting them until the point where the generator overloads and the security systems cut in.

If you have any power plant close to you that is being commissioned, make a study visit with a volt meter and you will see!

(Oh and I knew about the 50mA lethal current... I have studied all of these things... I am not worried about the safety aspects of a hybrid rally car in water... Cost of hybrid rally car and feasibility and many other things yes, but safety aspects no).

[Rally Power]

http://www.motoring.com.au/next-suba...hybrid-100477/

Rumours about next WRX generation. The first hybrid in rallying or the definitive end of N4?

[OldF]

One thing I almost forgot about is the resistivity. Maybe it has something to do with that it’s almost 40 years since I was studying electrical engineering.

However here have been talks about the resistance of water but water, as any other conductor, water don’t have a specific total resistance but the resistance (or impedance) depend on what kind of water (the resistivity of the conductor) and how much water is in question (the length and area of the conductor). The more water the less resistance.

With a cable it’s more simply because with a cable the electricity come in (usually) from one end and go out from the other end and the resistivity, length and area of the cable is known. With water it’s more complicated because in a case of an accident the circumstance varies a lot i.e. the type of water, the length and area of the water conductor.

The resistance is:

R (ohm) = resistivity of the conductor (ohm meter) * length of conductor (m) / area of conductor (m²)

As you can see in a case of electrical accident in water it can be difficult to assess the length and area of the water conductor and also with the resistivity if the type of water is not known.

Interesting article about bath tube accidents with self-testing (crazy). Nothing to do directly with hybrid cars but however with electricity and water.

http://www.powerlogic.com.au/Attachm...iegelmeier.pdf

As said in the summary the path electric source – human in – human out – water – ground or other terminal is more dangerous than the path electric source – water - human in – human out – water – ground or other terminal.

You have to remember that they are not in fact connected in parallel unless the battery pack is submerged and some idiot breaks into the car, opens the cover, and touches both the poles (plus and minus).

That is extremely unlikely. In a real situation where the battery pack or an MGU connected to the battery pack gets shorted by water (which already is unlikely), the connection is going to be water to human to water in parallel with water only and water to body shell to water (very much preferred by electricity) and water to earth to water... So human is about the last thing the battery pack will go through.

Also the voltage over human won't be 600v or 800v or whatever, as much of the current will pass through the water. ).

The case with my example was mainly to show that how a small fraction of the total current can be lethal to a human if a human body is in parallel with any other low level resistance.

In the picture below the human is in parallel with the load of the electric system. Imaging that the dotted line is water and the minus terminal is in water, the body and the water would be in series and parallel with the load. Now the question is: What is the probability for this kind of accident to happen. Luckily the bird is safe.



http://www.allaboutcircuits.com/text...-current-path/


Btw, idiots always exists. It seems that a very common electrical accident is when some idiots are climbing on the roof of a train.

http://www.tukes.fi/tiedostot/sahko_...nunen_2013.pdf

On page 137
APPENDIX 1. Fatal electrical accidents in the Nordic Countries in 2007-201

The latest one was this New Year eve. Someone had clime on the roof on a train and had burned sot bad that even the gender couldn’t be defined at the first place. It’s said that the safe distance from a train power line (25 kV) is at least 2 meter.

Voltage over human would be too small to even be felt (or probably even measured). If you put a volt meter across two points in water that you have shorted with high voltage you are going to get a very small voltage (if even detectable if you have a larger amount of water) as you can in theory see the water as veeeery many resistors in series and the voltage will distribute across them. If you measure between the terminals you are going to get 800v but across two points in the water, just a few micro volt (if even that). )

I’m far from an expert but after reading http://electronics.stackexchange.com...-as-a-resistor this maybe it’s the wrong way to measure the voltage just to put the small probes of a volt meter in the water. Maybe what you said (voltmeter across two points) was just an expression. As I said I’m not an expert in this case but as I understand to get the true value of the voltage/current (or measuring the resistance) true the water is to have electrodes covering the whole area of the water where current/voltage is applied to the water (+ terminal of a battery or the “hot” wire of a house case) and electrodes covering the whole area of water where the current goes back to the source, i.e. path from terminal to terminal in a battery case or a path from “hot” wire to ground in a house case or vice versa. (- terminal of a battery or the ground in a house case).

(Oh and I knew about the 50mA lethal current... I have studied all of these things... I am not worried about the safety aspects of a hybrid rally car in water... Cost of hybrid rally car and feasibility and many other things yes, but safety aspects no).

I didn’t doubt that you didn’t know about that. I didn’t remember the actual value, only that’s very small. That’s why I had to search for it.

If you ever witness a generator overload test, you can try this if you like. It is done by lowering all three phases into the water and shorting them until the point where the generator overloads and the security systems cut in.

If you have any power plant close to you that is being commissioned, make a study visit with a volt meter and you will see! )

No, we didn’t do such drastic laboratory works. And I won’t try it at home by putting the three phases of our sauna heater in the water.

[itix]

One thing I almost forgot about is the resistivity. Maybe it has something to do with that it’s almost 40 years since I was studying electrical engineering.

However here have been talks about the resistance of water but water, as any other conductor, water don’t have a specific total resistance but the resistance (or impedance) depend on what kind of water (the resistivity of the conductor) and how much water is in question (the length and area of the conductor). The more water the less resistance.

With a cable it’s more simply because with a cable the electricity come in (usually) from one end and go out from the other end and the resistivity, length and area of the cable is known. With water it’s more complicated because in a case of an accident the circumstance varies a lot i.e. the type of water, the length and area of the water conductor.

The resistance is:

R (ohm) = resistivity of the conductor (ohm meter) * length of conductor (m) / area of conductor (m²)

As you can see in a case of electrical accident in water it can be difficult to assess the length and area of the water conductor and also with the resistivity if the type of water is not known.

Interesting article about bath tube accidents with self-testing (crazy). Nothing to do directly with hybrid cars but however with electricity and water.

http://www.powerlogic.com.au/Attachm...iegelmeier.pdf

As said in the summary the path electric source – human in – human out – water – ground or other terminal is more dangerous than the path electric source – water - human in – human out – water – ground or other terminal.




The case with my example was mainly to show that how a small fraction of the total current can be lethal to a human if a human body is in parallel with any other low level resistance.

In the picture below the human is in parallel with the load of the electric system. Imaging that the dotted line is water and the minus terminal is in water, the body and the water would be in series and parallel with the load. Now the question is: What is the probability for this kind of accident to happen. Luckily the bird is safe.



http://www.allaboutcircuits.com/text...-current-path/


Btw, idiots always exists. It seems that a very common electrical accident is when some idiots are climbing on the roof of a train.

http://www.tukes.fi/tiedostot/sahko_...nunen_2013.pdf

The incident with the train is fairly easy... in that case the human is the only conductor connecting the power to earth and the super high voltage (16 kv in sweden... don't know what finnish train systems run) can actually arc the air to human due to the high voltage and conduct to earth. Just a shame that railway operators have to be responsible for these idiots... let them burn I say!

In the case of the rally car, we still have to conclude that both poles have to be earthed through the water for this to work. It is true that different kind of water conduct differently... distilled fresh water is the worst conductor and salt water the best (due to the ions and free electrons etc etc). We know that we need a relatively high voltage to create any current in a human person.

This is why 12v and 24v systems can be touched and nothing happens...

We also know that voltage in a system of resistances distribute over the highest resistor with the greatest voltage and the lesser resistors with lesser voltage when in series.

We also know that the most current pass "the path of least resistance".

Below is a very simplified diagram of the situation. In reality it is endlessly more complicated but it is a simple map to help us understand what happens.



As seen in the diagram (where I have lied a bit and connected the left hand of human to the minus pole... but hey, resistors are addable in series so), the voltage over human is distributed over water 4 (I named the waters differently but in reality as it is just one big body of water so we could all have named them the same but for understanding, better like this) and then human... so it won't be many volts over human as the body of water 4, even in salt water, have resistance per meter and cable area...

Now if human really was in series with water only and was touching the minus pole, 100% of the current would pass through human... but that is not the case because there is earth, water and body shell also in parallel and they are much preferred path of the current to take so the current passing through human will be microscopic... at best.

I’m far from an expert but after reading http://electronics.stackexchange.com...-as-a-resistor this maybe it’s the wrong way to measure the voltage just to put the small probes of a volt meter in the water. Maybe what you said (voltmeter across two points) was just an expression. As I said I’m not an expert in this case but as I understand to get the true value of the voltage/current (or measuring the resistance) true the water is to have electrodes covering the whole area of the water where current/voltage is applied to the water (+ terminal of a battery or the “hot” wire of a house case) and electrodes covering the whole area of water where the current goes back to the source, i.e. path from terminal to terminal in a battery case or a path from “hot” wire to ground in a house case or vice versa. (- terminal of a battery or the ground in a house case).

You need to remember that there is no ground in a battery system of a car (other than the bodyshell which is used as a common 0 of sorts... I guess you can regard that as ground but it is important to remember that it is not the ground you stand on).

The reason why trains and all other land based electricity is dangerous is because it returns through ground (yep, that is right, the 0 cables (blue) of almost all land based equipment today, including high voltage transformers etc etc, are earthed and return the current through ground... and yet you don't get fried when you put a shovel in the ground... same thing as the rally car in the water really). When you touch any live electric bit, it always wants to return to earth... which is exactly why the bird in your chart is fine even if it were to sit on a live wire where the insulation is gone... the bird does not touch earth.

No, we didn’t do such drastic laboratory works. And I won’t try it at home by putting the three phases of our sauna heater in the water.

I don't think your fuses would survive it and you probably have an earth fault breaker as well... so go ahead Ok no probably not, unforseen things will probably happen, but theoretically you'll be fine!

Generator tests are done without fuses and other safety equipment hahahaha, but there is a safety parameter... mostly because the pahses are live and bare and not because of the water... it is very interesting to watch

[Eli]

Since we now have (Plug-in) Hybrid Rally1 Cars, would you say it was the right move or do you guys think they should've gone away with it earlier than this season?

[pantealex]

Since we now have (Plug-in) Hybrid Rally1 Cars, would you say it was the right move or do you guys think they should've gone away with it earlier than this season?

not right move, should have continued with ICE gasoline cars.

#myopinion

(I understand that world is going Green but I still like my rallying with gasoline/diesel only)

[Sergiow]

Since we now have (Plug-in) Hybrid Rally1 Cars, would you say it was the right move or do you guys think they should've gone away with it earlier than this season?

Certainly not the right move. GTWC 24h Spa 2022, on July 28-31 there will be 65 cars participating, 23 PRO teams (including Valentino Rossi which already is providing the GT show with its biggest merchandising stand ) participating GT3s from Aston Martin, Audi, Bentley, BMW, Ferrari, Lamborghini, McLaren, Mercedes-AMG and Porsche, lined up by customer teams and those with official support.

https://it.motorsport.com/gtwc-endur...26282/?nrt=209

Unlike the Hybrid Rally1 Cars, all official GT3s can be acquired by customer teams. The only big draw back with GTWC (and WEC too) is that deadening BoP which is a disgrace for all true racing. But that doesn't matter here because it is the customer model which counts and that make the GT show a gold mine for the official constructors. With a rumored price tag of 0,5 mil dollar each GT3 they are much cheaper than the current Rally1 cars and the GT3s have much more road relevancy.