Technical graphs and images

[Trex]

Here we have our petrol motor's torque and power plots.

From about 120kph and up the PHEV will go into Parallel mode from Series mode regardless because there is more power available from the petrol motor if it is directly coupled to front wheels than getting the power through the generator in Series mode. Below about 120kph, down to 65kph, if more power and is needed from the petrol motor than it can produce in Parallel mode (if already in Parallel mode) it will drop back into Series mode. You can see the effect in this video:

https://www.youtube.com/watch?v=rbOmtzFj14M

Watch center display between power gauge and speedo gauge and see how it goes from Series mode into Parallel mode at about 120kph.

Of course his foot is flat to the floor on the accelerator. :lol:

Regards Trex.

Material from MMC and GtoGarrett on youtube.

 

[anko]

Hey, what happened to the credits? :mrgreen:

I don't think dashed lines are for serial mode. They show what you would get if parallel mode would engage at lower speeds. And thereby why parallel mode doesn't engage at lower speeds: not enough grunt.

The whole idea of serial mode isto allow the engine to make more revs and generate more power and torque while doing so.

 

[Trex]

Hey, what happened to the credits? :mrgreen:

I don't think dashed lines are for serial mode. They show what you would get if parallel mode would engage at lower speeds. And thereby why parallel mode doesn't engage at lower speeds: not enough grunt.

The whole idea of serial mode isto allow the engine to make more revs and generate more power and torque while doing so.

Hey anko,

Sorry old mate I will fix up the post straight away about the credits. I knew I forgot something. :lol: :lol:

If you look hard at the bottom of the graph you can just make out the words that I wrote.

I think it has something to do with the hv battery being less then < 30%. Can you check or translate what they are trying to say. We can edit it later.

Regards Trex.

 

[Trex]

Engine differences.

Image from MMC.

Regards Trex.

 

[anko]

If you look hard at the bottom of the graph you can just make out the words that I wrote.

I think it has something to do with the hv battery being less then < 30%. Can you check or translate what they are trying to say. We can edit it later.

Regards Trex.

You are right. It says so in the graph. I did not see that first. But it doesn't change the way I look at it: in serial mode, engine RPM is independent of vehicle speed and so is (within limits) engine output in terms of power and torque.

The document is a bit confusing. First, there are two tables, which I have combined into a single picture:

If you take into account tire size and gear ratios you can translate speeds into e-motor RPMs and thus torques into kWs. What the first table tells you is that with SOC>30% the e-motors can deliver 120 kW max (as of 55 km/h).

The second table table tells you that with SOC<30% the amount of torque at 55 km/h is half of what it is at SOC>30%. This would translate into max 60 kW. This suggests that with SOC<30% no power is drawn from the battery, only from the generator.

But in the text it says that at SOC<20% support from the battery is reduced and you will have max 60 kW / 135 Nm at 65 km/h, all coming from the generator. From the text and my own experience, I think the captions for the tables are wrong. I think the first table is for SOC>20% and the second for SOC<20% (Turtle mode).

 

[Trex]

Hi anko,

Thanks for sorting that out for us. I agree it should be <20% as from the first graph on page 1 of this discussion.

I have adjusted the graph above with green and yellow lines to take into consideration what you mean about the variable output of the generator in Series mode showing max output of generator, after losses, in Series mode.

I think those blue and red dashed lines are for lowest loading of the petrol motor (or generator) in Serial mode . I notice in my Phev that at 60kph the petrol motor never seems to stop running as though the generator is not putting out enough output to charge the hv battery for ev mode later ie no start (charge) stop (ev mode) of petrol motor at 60kph.

Regards Trex.

 

[thegurio]

Fantastic work Trex, and Anko..... It gives us a real understanding of the technical side of our cars!

Keep it up and get all the technicality you need!

What I would love is a better view of a cell of the battery. If that's possible of course?

 

[Trex]

Fantastic work Trex, and Anko..... It gives us a real understanding of the technical side of our cars!

Keep it up and get all the technicality you need!

What I would love is a better view of a cell of the battery. If that's possible of course?

On my behalf thanks for the kind words.

Will see if we can come up with something on the battery cell to put in this sticky.

Regards Trex.

 

[thegurio]

Fantastic work Trex, and Anko..... It gives us a real understanding of the technical side of our cars!

Keep it up and get all the technicality you need!

What I would love is a better view of a cell of the battery. If that's possible of course?

On my behalf thanks for the kind words.

Will see if we can come up with something on the battery cell to put in this sticky.

Regards Trex.

No problems, I could only imagine the effort that went in to producing it... Thanks in advance if you can get it.

 

[Trex]

A new item,



This is something I have been working on for a while and I hope it makes sense. It is basically a combination of the previous graphs plotted at the axles. Thanks for your help with this anko.

Regards Trex.

 

[Trex]

A request from thegurio,



I think this is a cell (there are 80 of them) from the Phev's Hv battery pack. This is the only one on GS Yuasa Corp website that comes close to the specs quoted by Mitsubishi and is same colour as seen on page 1 of this discussion or sticky.

Note it says 50Ah where the Phev specs shows 40Ah but I think this is because Mitsubishi derate the battery for longevity. This battery is 50Ah 6C discharge (300 amps) derated to 40Ah 5C (200 amps). Good for long life.

Regards Trex.

Material from GS Yuasa Corp

 

[anko]

This is something I have been working on for a while and I hope it makes sense. it is basically a combination of the previous graphs plotted at the axles. Thanks for your help with this anko.

Regards Trex.

Haha. You are welcome. Just a thought: torque from front E-motor at 120 km/h is about 65-ish Nm. Torque from the engine at that speed is about 170 Nm. But when comparing front motor gear ratio with engine gear ratio, I would think the E-motor is spinning more than 3 times as fast as the engine and therefore I would expect that, at 120 km/h, the E-motor would still deliver more torque (at the wheels) than the engine could?

 

[anko]

Yesterday, on a long stretch of motorway, I emptied my battery, started logging and hit charge (this was not a warm start). I aimed at continuing that way until it stopped charging, but I ran out of runway before I reached that point. Or actually, I ended up with enough EV range to reach my destination, before it stopped charging. Then I aborted my attempt. This is the graph for the run. Guess where I reached approx. 50% SOC ....

From top to bottom:
Blue = speed (about 100 km/h)
Red= rpm (about 2670)

Red = Torque
Blue = Power

Red = Inst. fuel consumption (about 11.2 l/100 km/h until I reach half way)

 

[Titan]

Nice logging but what am I supposed to infer?

 

[davebodger]

Nice logging but what am I supposed to infer?

I think he's trying to show that fuel economy is rubbish if you charge whilst driving on the motorway.
25mpg@62mph is not good!

 

[anko]

I think he's trying to show that fuel economy is rubbish if you charge whilst driving on the motorway.
25mpg@62mph is not good!

No, that is not what he was trying to show :mrgreen: . Whatever MPG you see is not bad at all, when you take in to account that you are gaining 'free EV miles' to be spent later. And then the average MPG will drop when you spend three free miles. Let's not forget, driving in normal mode (no charge, no save) beyond EV range does exactly the same thing. Except for a shorter period of time.

What he was trying to demonstrate is that fuel consumption goes down when SOC goes up. In our car, lower fuel consumption means less efficiency. For this reason, he is advocating not to keep SOC too high, during normal driving, by use of save or charge mode.

 

[gwatpe]

Hi,
Hope this works so here goes and thanks to anko for permission.



I know anko has posted this before but I was hoping these will be placed in a sticky in the Technical discussions so it can be found easily for new members etc.

Note the sawtooth lines on the graph.

Regards Trex.

Had my PHEV down to 21%SOC today and what do you know, Aircon still working and the turtle did not appear. AUS shipped PHEV may still have a different firmware version with lower limits. Will see if I can get the turtle to appear, with some data to match.

 

[Grigou]

- Aircon : maybe it was necessary for the battery cooling (what was the outside T° when you did this observation ?), so it worked also inside the car ?
- Turtle mode : the graph shows the limit at 20 °C, doesn't it ?

 

[gwatpe]

Aircon was still working in the cabin.

OBD had the %SOC at 21%.

Car recovered some %SOC and the saw tooth pattern occurred from 28.5%SOC to 30.5%SOC, and this sort of matches up with the graph. It seems that only under some extremes of load, that the PHEV cannot keep up with the demands, and my PHEV is not any different to others. If the hill had been just a little longer, then possibly the turtle would have appeared. Have another hill to test on that is about 50% longer with a higher climb, but not quite as steep.

Will be looking at the brakes soon. Preliminary data is showing that the regen copes well with all but severe stops.

The white trace is mechanical brakes activated

The blue is current into the battery. There is some recharging with NORMAL mode as I was testing with the depleted battery.

This was a windy hilly test, with many 40kph and 50kph bends. I did not race the PHEV, as it was at night. Was just over half an hour of driving. The distance and fuel has to be halved as I am sampling 2x per second, and have yet to readjust the app for that.

The PHEV calculated an average petrol economy of 6.8L/100km and I calculated 6.6L/100km from the RAW OBD data. I am now using the Torque PRO latest versions calculated L/100km and this correlates better with the brim to brim petrol and distance travelled in other tests, with the PHEV calculated L/100km.

 

[anko]

It seems that only under some extremes of load, that the PHEV cannot keep up with the demands, and ...

Could it be that the PHEV steps up when needed? As we know normally thePHEV tries to maintain approx. 30% SOC at motorway speeds. Returning from my summer vacation, while towing my caravan into a strong headwind, the car was clearly not able to maintain this 30% SOC. The percentage plummeted to approx 21 - 22. Once there, the PHEV started to make more of an effort and managed to crawl back to 25%, when it eased off again. This resulted so to speak in a 'secondary' hysteresis cycle, which I had a feeling the PHEV could have maintained forever. It managed to do so for 2 hours anyway.