Series Hybrid Mode - Racing Engine question

[PhevGeorge]

Hello everyone, I’m new and this is my first post. I have spent a lot of time reading this excellent forum, since before purchasing the car and feel that I have a pretty good understanding of the technology, so thank you all for your input creating such an informative technical reference.

Last November I purchased a 2015 UK GX4H with 26K miles, then shortly afterwards PHEV Watchdog for Android. The SOH is a little disappointing, but I understand well within the Warranty at 80.3% (based on 38Ah Battery) The car is a real pleasure to drive, seems to behave as expected, with the exception of one irritating situation:

When climbing a significant hill, even with a full SOC, at speeds above around 35 MPH, the engine kicks in when PHEV Watchdog is shows battery drain exceeding about 50KW. This I can understand as it is a heavy beast to pull up a steep hill, but very often the Engine will run between 3000 – 4300 RPM. – and I do drive with a very light throttle.
This is an awful racket and seems un-necessary, for an unloaded vehicle with just a driver to maintain 40MPH going up a hill. If it is safe and legal to increase speed to about 45MPH, then I can usually force Parallel Mode, by pressing the Charge or Save buttons which of course, quietens everything down.

So, before I contact the Mitsubishi dealer, that supplied the car, I would really like to hear from any forum members whether “they all do it?”, because I’m sure that’s what the dealer will tell me!

Thank you in anticipation

 

[AndyInOz]

Hi there,

I think the engine is running to provide more electric power to the motors to get you up the hill.

This would be considered normal.

I don't think it is possible to set parallel mode via any combination of the buttons.

Parallel mode is when the engine is directly driving the front wheels while the electric motors are also providing power.

This mode is only in use when the car is at or above a particular speed. (80 km/h IIRC)

 

[greendwarf]

Yes, this is a regular complaint but is quite normal and a function of both the technology AND the unnatural quiet of the rest of your driving. In practice it is no different to changing down in an ICE to improve performance up a gradient and probably no louder than a similar 2 litre 2 ton SUV under the same conditions. Eventually you get used to it.

 

[jaapv]

And people forget that they would have shifted down to climb a hill on a conventional car as well, which would have increased revs.

 

[ThudnBlundr]

At low speeds, the car decides on the engine revs required based on efficiency and power required. If the battery is below ~80%, any spare power will be sent to the battery anyway, so it's not as if the power is wasted. In parallel mode at higher speeds, the engine speed is tied to road speed so can only supply the power at the specific engine rpm unless it disconnects the engine and reverts to series mode.

 

[PhevGeorge]

Thank you all for your responses

So it seems that I'll just have to live with my car sounding like a "Daf Variomatic" of the 1950s, when negotiating steep hills at 40MPH. I was rather hoping that there would be someone out there with Watchdog or EVBatmon that would say their car behaves exactly the same under these circumstances.

That said, I have just returned from a trip of over 500 miles and the car is pretty impressive in every other respect!

 

[user 3575]

Thank you all for your responses

So it seems that I'll just have to live with my car sounding like a "Daf Variomatic" of the 1950s, when negotiating steep hills at 40MPH. I was rather hoping that there would be someone out there with Watchdog or EVBatmon that would say their car behaves exactly the same under these circumstances.

That said, I have just returned from a trip of over 500 miles and the car is pretty impressive in every other respect!

I totally understand were you are coming from I was the same, now i except as the norm

 

[jaapv]

Thank you all for your responses

So it seems that I'll just have to live with my car sounding like a "Daf Variomatic" of the 1950s, when negotiating steep hills at 40MPH. I was rather hoping that there would be someone out there with Watchdog or EVBatmon that would say their car behaves exactly the same under these circumstances.

That said, I have just returned from a trip of over 500 miles and the car is pretty impressive in every other respect!

Well, the difference is that the DAF would not be able to get up the hills that make your PHEV deploy full power. :lol:

 

[greendwarf]

Not even in the Dutch Alps?

 

[kpetrov]

The threshold for parallel mode is 65km/h or 41mph and yes it can be forced. Just press CHARGE and when the engine is warmed up it will connect directly to the wheels.
On series mode the vehicle decides the RPM. It shouldn't be waste since the energy is going to battery, but it sounds wasteful I agree.

 

[PhevGeorge]

Thanks Kpetrov for confirming what I thought was true about forcing parallel mode, but I hadn't realised that the engine needed to be up to temperature.

The purpose of my post was to find out if my PHEV is performing properly, as it is fairly new to me. So if there is anyone out there with PHEV Watchdog that could confirm whether it is normal for the engine to run between 3000 - 4000 RPM, when progressing up a steep hill at 40 MPH in Series mode, then I would be very grateful.

I'm a bit concerned that perhaps the current sensor might be a bit inaccurate as the engine starts and it does all this revving even with a fully charged battery when the load (according to the Watchdog is only about 50KW

 

[AndyInOz]

I think you may have misunderstood.

If you are travelling below the speed threshold, you cannot "force" the car into parallel mode, you cannot make the engine turn the wheels below that speed.

If you are travelling above the speed threshold, you are already in parallel mode, unless you are coasting downhill or decelerating.

 

[jaapv]

The threshold for parallel mode is 65km/h or 41mph and yes it can be forced. Just press CHARGE and when the engine is warmed up it will connect directly to the wheels.
On series mode the vehicle decides the RPM. It shouldn't be waste since the energy is going to battery, but it sounds wasteful I agree.

No it will not do that. When you press Charge the engine will start running to charge the battery without sconnecting to the wheels. That only happens when the car determines that this is the most efficient way of running the car.

 

[jaapv]

I think you may have misunderstood.

If you are travelling below the speed threshold, you cannot "force" the car into parallel mode, you cannot make the engine turn the wheels below that speed.

If you are travelling above the speed threshold, you are already in parallel mode, unless you are coasting downhill or decelerating.

If you are travelling above the speed threshold the car will decide whether it will be in series or parallel mode depending on power demand and road speed.

 

[greendwarf]

I think the point being made, is that the question of series or parallel only applies when the ICE is running, which can be "forced" by going into Charge mode even if you would otherwise be in EV?

 

[kpetrov]

The threshold for parallel mode is 65km/h or 41mph and yes it can be forced. Just press CHARGE and when the engine is warmed up it will connect directly to the wheels.
On series mode the vehicle decides the RPM. It shouldn't be waste since the energy is going to battery, but it sounds wasteful I agree.

No it will not do that. When you press Charge the engine will start running to charge the battery without sconnecting to the wheels. That only happens when the car determines that this is the most efficient way of running the car.

That's the point if you are up to the speed (when it is available over 65km/h or 41mph) parallel is the most efficient way of running the car.
Of course when I said it could be "forced" it's not up to the driver only, the vehicle may not go parallel if some conditions are not met, like
engine temperature, not sure what else. When very cold it takes more time but not only for engine warm up. I believe battery temp. play a role as well.

 

[jaapv]

It is not only speed, power demand is an even more prominent parameter.

 

[kpetrov]

In parallel hybrid mode the vehicle has the maximum power available.
If the power demand you are talking about is greater than that, well then in any other mode the vehicle will struggle even more.
We should talk realistic scenario.

 

[jaapv]

It has not. Just try it when you are driving in parallel at medium speed. Depress the accelerator demanding full power and it will go to Series to bring the ICE revs into the full power range of the ICE. At high speed it will stay in parallel, as the ICE revs are already in the full power band.

 

[kpetrov]

Yep at 65-70km/h you may not have max power and parallel may not be the most powerful mode but it is very questionable. The torque over 70km/h is almost constant. What I can see from the last paragraph on the picture contradict your statement.
What is medium and high speed BTW?