Percentage EV when running in hybrid mode.

[Trex]

I am still catching up on posts but I am now on the bottom of the first page of the technical discussion where gwatpe did his Australian road trip (it looks like he had fun).

Now at the back pages of the topic the discussions sort of went off on a tangent (seems to happen regularly here :lol: ) debating percentages of EV when running in hybrid mode.

This I wish to discuss.

Now back when I was discussing what I called the phev's virtual electric overdrive I did some calculations using the next graphs that went like this (I love copy and paste it sure saves typing):


graphs from anko

The first thing to do is get all the quantities into minutes for such a short trip of 9.16Kms.
92.75kph = 1.546 km/min
10.03Lts/h = 0.167Lts/min
Now the trip of 9.16km distance divided by our 1.546km/min = 5.925 min
If the petrol motor had run all the time on this trip at 0.167Lts/min X 5.925 min = 0.989Lts consumed
But it did not run all the time and used 15.32km/Lt so 9.16km divided by 15.32km/L = 0.598Lts for 9.16km
Now the fun bit 0.598Lts used divided by 0.989Lts if motor ran all the time = 0.605 X 100 = 60.5% of the time motor actually running!

Now I have cut the stuff out that is not applicable to this topic and just kept the calculation that shows how much the motor ran on this test using a MUTT-III

Note the "60.5% of the time motor actually running!" on the last line.

So 39.5% EV in this test.

Now for me personally I have seen that approx 40% EV figure, on trips away from the grid charge, (and not counting the grid charge) regularly on my MMCS so I totally believe the Mitsubishi test.

It still blows me away how efficient the Phev is by charging the drive battery (whenever the petrol motor runs) so it can ev later.

A 1.8 tonne 4wd with the aerodynamics of a brick getting 6.5l/100k at 92kph (with a petrol motor) as seen in this is graph is pretty bloody good. :lol:

So folks check your gauge and see if you get something similar.

Regards Trex.

 

[gwatpe]

I am predicting that a driver, who can perform a similar constant speed test in SAVE, mode, or say NORMAL mode with a depleted battery that at 80kph, the economy returned for a 20-30km test would be about 20km/L, or 5L/100km or 56 MPimpG. This would be a parallel hybrid test.

I have plotted some of my own test data in red with the data from the MMC test in blue

Would be good with the 80kph data.

My around AUS trip returning 8L/100km seems close enough to right on the money.

I have some data points for my own %EV that can be included with the data "trex" has shared.

%EV vs Speed

Others may have data that can be added to the plot?

 

[Trex]

I am predicting that a driver, who can perform a similar constant speed test in SAVE, mode, or say NORMAL mode with a depleted battery that at 80kph, the economy returned for a 20-30km test would be about 20km/L, or 5L/100km or 56 MPimpG. This would be a parallel hybrid test.

I have plotted some of my own test data in red with the data from the MMC test in blue

Would be good with the 80kph data.

My around AUS trip returning 8L/100km seems close enough to right on the money.

I have some data points for my own %EV that can be included with the data "trex" has shared.


%EV vs Speed

Others may have data that can be added to the plot?

Gday gwatpe,

Are you sure the % Ev falls that quickly like shown in your graph. I need to find a long stretch of 110kph zone to test that.

Where do you do 120kph in Australia besides NT (without losing you license) to know that its 0% Ev at 120kph. That I find very surprising. I will not be testing that. :lol: :lol:

Mine is a lot closer to 40% EV at 100kph and at 60kph on the test I did the other day the fuel computer on the reset read 10L/100k and then when it did its hybrid thing charge, ev mode etc it would be averaged out at 6.7L/100k which tells me it was worse than 50 % EV you got which makes sense because of series mode inefficiency.

But normally I am in Ev mode at 60kph and avoiding series mode and mine just sits around the approx 40% EV at the speeds I drive.

Regards Trex.

 

[gwatpe]

The 0% at 120kph is the point where all the energy from the ICE is needed to overcome the losses to move it. Has been mentioned many times on the forum, so I used it as "a given".

I would expect the graph to be somewhere the shape that comes out. More objective data would of course help.

It would help if the PHEV was able to give the actual distance and actual litres that were used to calculate the mileage that is displayed. Retro fitting my 1977 CompuCruise would give precisely this sort of data without connecting to the car computer. Now when does warranty run out?

 

[Grigou]

The 0% at 120kph is the point where all the energy from the ICE is needed to overcome the losses to move it. Has been mentioned many times on the forum, so I used it as "a given".

I would expect the graph to be somewhere the shape that comes out. More objective data would of course help.

It would help if the PHEV was able to give the actual distance and actual litres that were used to calculate the mileage that is displayed. Retro fitting my 1977 CompuCruise would give precisely this sort of data without connecting to the car computer. Now when does warranty run out?

Unfortunately I don't have any datas (still waiting my chinese ELM327 ), but when I drive at 120 kph on motorways (about 125 kph on dashboard) I can see the diagram showing alternatively EV mode and parallel mode. Not in a ratio 40/60 % of course, but perhaps 30/70% or 20/80 or so ...

Anyway, I don't understand why you say that 120 kph is the point where all the energy from the ICE is needed to overcome the losses to move it.
At this speed the drive resistance is 100 N.m and the available engine's torque in parallel mode is about 175 N.m

 

[Neverfuel]

I don't think the graph will reduce to zero at 120kph as this is the upper limit of the "sweet spot" and there is still power available from the generator to continue to charge the battery in spite of the torque requirement to overcome air resistance. Even if the battery is seemingly "depleted" - the car can still eat into its 30% saved SOC for acceleration until the turtle mode and can still supply 59.6kw (60kw after losses) to the rear motor all the way upto 170kph. This kinda means we can never be sure how much is delivered by the engine alone or a combination of the engine and drive battery, even under similar driving test conditions - the unknown variable will always be the switching methodology IMHO.

 

[Neverfuel]

Hi Trex

Welcome back - it is always good to read through your analysis.

I struggle to work out what some of the car's displays are trying to tell me sometimes and have now long since forgotten about the short and long term history graphs for example as they do not go back far enough or show enough detail to gain any accurate long term picture (for me anyway - but if anyone knows how to make best use of them, I am willing to listen). What I would like to know is whether your tests PROVE that the automatic (4 hour short term) and manual (long term between resets) figures on the %EV driving figure on the car MMCS & central display are accurate. For example - have you got an average fuel consumption figure with zero charge left and then done a brim to brim fuel check over a certain distance on a single journey. If it can be proved that the %EV figure is reliable, then by measuring total mileage divided by the number of litres added during the driven miles and subtracting the %EV miles driven, we should get a clear understanding of what the actual mpg / l/100km is on just the ICE.

Once we know our cost per month for grid charging; the rough mileage from FREE charging (either fast, solar or stolen electricity), we could convert that into the equivalent number of litres that the electricity would have bought us and instead of mpg / mpge a figure of cost per mile / litre would be a better indicator of how we use our cars - but only on a single country basis due to differing electricity / petrol costs and exchange rates.

It would be nice if we could all develop a set of calculations that would let owners compare apples with apples in each country. I am sure that between the published figures and several versions of experiments on the forum that most people are fairly confused, which means that although the information in each persons interpretation is interesting, it just makes the whole topic more fuzzy rather than clearing it up.

Thoughts please?

 

[Regulo]

I am sure that between the published figures and several versions of experiments on the forum that most people are fairly confused, which means that although the information in each persons interpretation is interesting, it just makes the whole topic more fuzzy rather than clearing it up. Thoughts please?

I was following this quite happily, then I lost it! . I agree with Trex - those of a nervous disposition should stay clear of the deeper discussions in this section. Keep calm and carry on digging, I doubt you'll ever get to the bottom of these questions without recourse to a fully equipped vehicle testing laboratory. On the public roads there are so many variables.

 

[Neverfuel]

I am sure that between the published figures and several versions of experiments on the forum that most people are fairly confused, which means that although the information in each persons interpretation is interesting, it just makes the whole topic more fuzzy rather than clearing it up. Thoughts please?

I was following this quite happily, then I lost it! . I agree with Trex - those of a nervous disposition should stay clear of the deeper discussions in this section. Keep calm and carry on digging, I doubt you'll ever get to the bottom of these questions without recourse to a fully equipped vehicle testing laboratory. On the public roads there are so many variables.

Don't be fooled Regulo - I'm following ALL the technical conversations with interest (bit confused by the PID conversation though, although I think they are doing some amazing work). Just making a point that we could probably develop a set of parameters and calculations that many more people can both understand and contribute to. I have my own way of working out my usage figures, and so have you, so has Anko, Gwatpe, Maby Trex etc. I am quite interested in establishing a benchmark that more people can contribute to, because:

A) I have a genuine interest in the technology.
B) It will be good to compare the new model against the old.
C) It can only benefit new and less engaged older members.

Only adding my twopenneth - that is what makes the forum interesting

 

[Trex]

The 0% at 120kph is the point where all the energy from the ICE is needed to overcome the losses to move it. Has been mentioned many times on the forum, so I used it as "a given".

I would expect the graph to be somewhere the shape that comes out. More objective data would of course help.

It would help if the PHEV was able to give the actual distance and actual litres that were used to calculate the mileage that is displayed. Retro fitting my 1977 CompuCruise would give precisely this sort of data without connecting to the car computer. Now when does warranty run out?

No comment on 120kph but our European PHEVers (is that a word I can use) should be able to help here.

"Now when does warranty run out?" :lol: :lol: Most people never want the warranty to run out but some of us here do so we can modify our cars. That is a classic gwatpe. :lol: :lol:

Regards Trex.

 

[Trex]

The 0% at 120kph is the point where all the energy from the ICE is needed to overcome the losses to move it. Has been mentioned many times on the forum, so I used it as "a given".

I would expect the graph to be somewhere the shape that comes out. More objective data would of course help.

It would help if the PHEV was able to give the actual distance and actual litres that were used to calculate the mileage that is displayed. Retro fitting my 1977 CompuCruise would give precisely this sort of data without connecting to the car computer. Now when does warranty run out?

Unfortunately I don't have any datas (still waiting my chinese ELM327 ), but when I drive at 120 kph on motorways (about 125 kph on dashboard) I can see the diagram showing alternatively EV mode and parallel mode. Not in a ratio 40/60 % of course, but perhaps 30/70% or 20/80 or so ...

Anyway, I don't understand why you say that 120 kph is the point where all the energy from the ICE is needed to overcome the losses to move it.
At this speed the drive resistance is 100 N.m and the available engine's torque in parallel mode is about 175 N.m

Hi Grigou been awhile


Yes a valid point about the torque and I will even bring in the image that shows it. Why. Because I love pretty pictures. :lol:


Material from anko

Plenty of excess torque to drive the generator if Mitsubishi want to do so at 120kph (bottom axis).

Regards Trex.

 

[Trex]

Hi Trex

Welcome back - it is always good to read through your analysis.

I struggle to work out what some of the car's displays are trying to tell me sometimes and have now long since forgotten about the short and long term history graphs for example as they do not go back far enough or show enough detail to gain any accurate long term picture (for me anyway - but if anyone knows how to make best use of them, I am willing to listen). What I would like to know is whether your tests PROVE that the automatic (4 hour short term) and manual (long term between resets) figures on the %EV driving figure on the car MMCS & central display are accurate. For example - have you got an average fuel consumption figure with zero charge left and then done a brim to brim fuel check over a certain distance on a single journey. If it can be proved that the %EV figure is reliable, then by measuring total mileage divided by the number of litres added during the driven miles and subtracting the %EV miles driven, we should get a clear understanding of what the actual mpg / l/100km is on just the ICE.

Once we know our cost per month for grid charging; the rough mileage from FREE charging (either fast, solar or stolen electricity), we could convert that into the equivalent number of litres that the electricity would have bought us and instead of mpg / mpge a figure of cost per mile / litre would be a better indicator of how we use our cars - but only on a single country basis due to differing electricity / petrol costs and exchange rates.

It would be nice if we could all develop a set of calculations that would let owners compare apples with apples in each country. I am sure that between the published figures and several versions of experiments on the forum that most people are fairly confused, which means that although the information in each persons interpretation is interesting, it just makes the whole topic more fuzzy rather than clearing it up.

Thoughts please?

Hi Neverfuel. Thankyou for your welcome back.

"My analysis." Most people might say "oh no not this crap again". :lol: I am a bug eyed little kid trying to understand things. :?

Now "short and long term history graphs" same I never use them anymore.

"What I would like to know is whether your tests PROVE that the automatic (4 hour short term) and manual (long term between resets) figures on the %EV driving figure on the car MMCS & central display are accurate."

Now that is a good question. I just love questions and I ask them all the time. Now as I have said in a another topic the only way I can be accurate I think is to :

1. Empty the grid charge first even if that includes highway. Takes that grid charge straight out of the question.
2. Reset either manual or auto fuel economy computer or both.
3. Take measurements from there on.

So by being careful not to start the Petrol motor up in 1. above (so the % EV will show 100% at that time ) and then when the petrol motor starts (from empty drive battery) I do 2. above so I can compare my result with what say Mitsubishi got in their result for instance. Their test was done with a empty drive battery.

"For example - have you got an average fuel consumption figure with zero charge left and then done a brim to brim fuel check over a certain distance on a single journey."

I have done one brim to brim test. It takes 3.2 L to charge the drive battery when stopped (which I posted here). I know, I am anal. :lol: But I have done a first click cutoff, on the fuel bowser, test once just to check the fuel computer. I just use the Phev's fuel computer because we all have one.

As for the rest of your post let me put it this way. I hate the grid charge. :lol: and get rid of it straight away even on the highway if I am taking measurements. But mainly for the reason I stated here in another topic:

"I find I cannot take accurate measurements while ever the grid charge is in my Phev . Again how are we ever going to compare figures if we do not have a level playing field?. I can hear you saying "ok but I will press save and then reset the fuel computer" but I found out nearly 18 months ago (never touch the save button now) even then the SOC can drift which can affect my results. Or I forgot to note my measurement before using some more of the grid charge."

and here:

"But the way I am doing it I can even compare cars that are not plug-in and even other hybrids like my old Prius.I know the grid charge has not biased my measurements but if I started to include them my fuel economy figures would look even better especially on shorter trips and that is the point of why I do not."

Note the "I forgot to note my measurement before using some more of the grid charge" and "even then the SOC can drift".

Looking back on that statement now I think if people are careful when pressing the Save button and then resetting the fuel computer and making sure the SOC does not drift we can easily compare results and I am being too bloody anal again :lol:

Sure we might have to include the maximum speed we travelled at or whether we were towing a caravan :lol: but I do not think we have to be too precise. I do NOT expect a totally lab type of comparison.

After all that I bet you regret asking your questions. :lol:

Regards Trex.

 

[Trex]

I am sure that between the published figures and several versions of experiments on the forum that most people are fairly confused, which means that although the information in each persons interpretation is interesting, it just makes the whole topic more fuzzy rather than clearing it up. Thoughts please?

I was following this quite happily, then I lost it! . I agree with Trex - those of a nervous disposition should stay clear of the deeper discussions in this section. Keep calm and carry on digging, I doubt you'll ever get to the bottom of these questions without recourse to a fully equipped vehicle testing laboratory. On the public roads there are so many variables.

Hi Regulo,

I think I might call you the "ninja techie" that downplays his powers. :lol: and I totally mean that in a good way.

But seriously I love people asking questions (I do all the time ) and I certainly do NOT know all the answers. I get sad when people give in and complain and say its all too hard and do not give the PHEV or themselves a chance.

Regards Trex.

 

[Trex]

I am sure that between the published figures and several versions of experiments on the forum that most people are fairly confused, which means that although the information in each persons interpretation is interesting, it just makes the whole topic more fuzzy rather than clearing it up. Thoughts please?

I was following this quite happily, then I lost it! . I agree with Trex - those of a nervous disposition should stay clear of the deeper discussions in this section. Keep calm and carry on digging, I doubt you'll ever get to the bottom of these questions without recourse to a fully equipped vehicle testing laboratory. On the public roads there are so many variables.

Don't be fooled Regulo - I'm following ALL the technical conversations with interest (bit confused by the PID conversation though, although I think they are doing some amazing work). Just making a point that we could probably develop a set of parameters and calculations that many more people can both understand and contribute to. I have my own way of working out my usage figures, and so have you, so has Anko, Gwatpe, Maby Trex etc. I am quite interested in establishing a benchmark that more people can contribute to, because:

A) I have a genuine interest in the technology.
B) It will be good to compare the new model against the old.
C) It can only benefit new and less engaged older members.

Only adding my twopenneth - that is what makes the forum interesting

I have enjoyed your posts Neverfuel and you have certainly made me think.

Please ask more questions if you do not understand anything I (or I have left anything unanswered) or anyone else says and yes it makes the forum interesting.

Regards Trex.

 

[Grigou]

Hi Grigou been awhile


Yes a valid point about the torque and I will even bring in the image that shows it. Why. Because I love pretty pictures. :lol:


Material from anko

Plenty of excess torque to drive the generator if Mitsubishi want to do so at 120kph (bottom axis).

Regards Trex.

... and we can add that @120 kph (~3175 RPM = 4500/170*120) the engine's power wich matches with 100 N.m is about 33 kW (if I have not made a mistake in the conversion : 3175 RPM --> 53 RPSecond --> 332 Rad/S * 100 N.m --> 33 kW). I like metric system :mrgreen:

 

[anko]

The first thing to do is get all the quantities into minutes for such a short trip of 9.16Kms.
92.75kph = 1.546 km/min
10.03Lts/h = 0.167Lts/min
Now the trip of 9.16km distance divided by our 1.546km/min = 5.925 min
If the petrol motor had run all the time on this trip at 0.167Lts/min X 5.925 min = 0.989Lts consumed
But it did not run all the time and used 15.32km/Lt so 9.16km divided by 15.32km/L = 0.598Lts for 9.16km
Now the fun bit 0.598Lts used divided by 0.989Lts if motor ran all the time = 0.605 X 100 = 60.5% of the time motor actually running!.

How about simply deciding 9.25 by 15.32 ... (average consumption per 100 km / consumption per 100 km while engine is running). That will get you there much quicker .... :mrgreen:

 

[anko]

Unfortunately I don't have any datas (still waiting my chinese ELM327 ), but when I drive at 120 kph on motorways (about 125 kph on dashboard) I can see the diagram showing alternatively EV mode and parallel mode. Not in a ratio 40/60 % of course, but perhaps 30/70% or 20/80 or so ...

At 120 km/h it might. But at 121 real km/h it will stop doing so. This is not like "somewhere around 120 km/h it reaches the point where it can no longer produce electricity for EV range". No, this is a hard switch. As if you have just changed cars.

It will change to a alternating pattern of low engine load (between 50 and 60%, IIRC) / high engine load (approx. 75%). During the periods of low engine load, power is taken from the battery and fed into both motors and the generator to eliminate E-drag (the rear motor actually produces very little torque, liker 15 Nm or so). When the SOC hits the low water mark, the engine shifts to the higher load state and the SOC is lifted again to the high water mark. And so on.

 

[anko]

The 0% at 120kph is the point where all the energy from the ICE is needed to overcome the losses to move it. Has been mentioned many times on the forum, so I used it as "a given".

This is not true. The 0% EV at 120+ km/h is per design (see my previous response as well).

It couldn't be because the engine runs out of power. As our torque curve is almost flat, power output of the engine increases almost linear with increasing RPM/ speed. But power needed to drive increases much faster with increasing speed. If the engine was giving all it had at 120, it would not be able to go any faster, other than by exhausting the battery. And that would mean we could not do 120+ km/h sustained. And we know we can ....

 

[anko]

the unknown variable will always be the switching methodology IMHO.

My Torque Pro dashboard tells me exactly what the engine output is (in terms of % of max output at that engine speed), as well as output of front and rear E-motor (in terms of kW) and the battery charge current. So, I think we can know.....

 

[anko]

Plenty of excess torque to drive the generator if Mitsubishi want to do so at 120kph (bottom axis).

Regards Trex.

I think I've mentioned this before, but I am pretty sure the engine favours to deliver 75% of it's maximum torque at any RPM. Less if the battery is not willing to access the surplus power (because of a too high SOC) but only more if driving conditions require so. So, when 75% or more of available engine power is needed for driving, charging stops.

But at 121 km/h, only about 50 - 60% of engine power is needed for driving. And still there is no charging in normal mode. Like I said, above 120 km/h, it is a different car.