Fusion Hybrid Powertrain Technical Analysis with Torque Pro & a ScanGauge

[larryh]

Additional observations for the Fusion Energi using Torque can be found here and in subsequent posts: http://www.fordfusionenergiforum.com/topic/1880-obd-ii-data-for-ice/?p=12923

[hybridbear]

Hybrid battery temp is measured in Celsius. When shown in Fahrenheit on the ScanGauge or Torque Pro it shows with decimal places, but it only moves in increments of 1.8F or 1C. The only numbers reported are whole numbers in Celsius.

[larryh]

The car returns a number between 0 and 255 for HVB temperature So it can only return 256 different values. That results in the quantization that you are observing. The 9/5 = 1.8 comes from the conversion from Celcius to Fahrenheit. The conversion formula to Fahrenheit is:

 

A*(9/5)-58,

 

where A ranges from 0 to 255.

[larryh]

I have added quite a few additional posts regarding details of how the eCVT operates in the Fusion Energi:

 

"http://www.fordfusionenergiforum.com/topic/1880-obd-ii-data-for-ice/?p=13310"

[hybridbear]

When the FFH does the "laggy empower gauge" (described here) the ICE is working as an air compressor like when using engine braking when descending a mountain. This is very inefficient when the car does this. When this happens the ICE is consuming 1-2 kW of mechanical power @ ~900 RPM due to it having negative torque of 10-20 Nm. In most of my observations where this has happened the car is thus driving using power from the HVB. It must take extra power out of the HVB to overcome the resistance of the ICE.

 

I'd like to try to figure out what causes the FFH to behave this way at times to be able to stop it. In a number of my observations this behavior continues for more than 10 seconds which consumes a fair bit of power from the HVB.

[hybridbear]

For my car with the 18-inch rims & tires the wheel speed equals 13.058(MPH). That is the average of the 2 regression equations shown in the charts below.

Left Wheel RPM vs MPH

 

Right Wheel RPM vs MPH

 

This means that the circumference of my tires is: 80.869965 inches.

@ 60 MPH my tires are rotating at a rate of 783.48 RPM

That means that in one minute they would rotate 783.48 times and cover 1 mile.

5280 feet divided by 783.48 tells us that each revolution covers 6.73916 feet or 80.869965 inches.

 

This is slightly off from what Discount Tire's calculator shows for my tires.

Edited May 8, 2014 by hybridbear

[acdii]

What about the 17" tires?

[larryh]

I have measured the circumference of the 17" tires using the same technique.

 

Wheel rpm = 13.438 x mph. So the tire circumference is 78.58312.

The 18" tires are 80.869965/78.58312 = 1.029 times larger than the 17" tires.

 

But note that this measurement is done with the car's weight on the wheels. The circumference would measure larger if the full weight of the car were not pressing down on the wheels.

Edited May 10, 2014 by larryh

[larryh]

When the FFH does the "laggy empower gauge" (described here) the ICE is working as an air compressor like when using engine braking when descending a mountain. This is very inefficient when the car does this. When this happens the ICE is consuming 1-2 kW of mechanical power @ ~900 RPM due to it having negative torque of 10-20 Nm. In most of my observations where this has happened the car is thus driving using power from the HVB. It must take extra power out of the HVB to overcome the resistance of the ICE.

 

I'd like to try to figure out what causes the FFH to behave this way at times to be able to stop it. In a number of my observations this behavior continues for more than 10 seconds which consumes a fair bit of power from the HVB.

 

I think the explanation for this can be found in the following patent: http://www.google.com/patents/US6600980.

 

This invention provides a strategy and system for a hybrid electric vehicle (HEV) that is not equipped with a hydraulic torque converter wherein a generator motor is utilized to maintain engine rotational velocity during up-shifting of the vehicle transmission in situations where the throttle of the engine is released. This invention can reduce undesirable torque reversals during up-shifting of the vehicle transmission in such situations where the throttle of the engine is released.

 

The engine appears to be directly connected to the wheels via the planetary gear system. When turning off the engine, the planetary gear system must up-shift to a lower gear ratio between the engine and the wheels so the engine can stop (when the engine is stopped, the final gear ratio is 0). If the ICE stops too fast, before the up-shift occurs, it will cause undesirable negative torque at the wheels, slowing the car down. The generator is used to maintain the engine rpm until the up-shift can occur.

 

But according to the patent, this occurs for only a second or so. So I'm not exactly sure what is going on.

Edited May 10, 2014 by larryh

[hybridbear]

_{I made some updates to the first post about the Power Flow screens & grille blocking. Updates are in red.}

[lolder]

When the FFH does the "laggy empower gauge" (described here) the ICE is working as an air compressor like when using engine braking when descending a mountain. This is very inefficient when the car does this. When this happens the ICE is consuming 1-2 kW of mechanical power @ ~900 RPM due to it having negative torque of 10-20 Nm. In most of my observations where this has happened the car is thus driving using power from the HVB. It must take extra power out of the HVB to overcome the resistance of the ICE.

 

I'd like to try to figure out what causes the FFH to behave this way at times to be able to stop it. In a number of my observations this behavior continues for more than 10 seconds which consumes a fair bit of power from the HVB.

I think when the ICE is braking downhill there is no energy coming out of the ( full ) HVB. The traction motor provides the electricity to operate the generator's coupling of the wheels to the ICE. Whenever the ICE stops or starts, the EV system puts appropriate transients into the mix so nothing is felt in the drive train. Ford has been the master at this. When the ICE starts, it is motorized to it's scheduled operating RPM and then the spark and fuel injectors are activated. As the ICE torque goes from negative to positive, the system produces smooth torque at the wheels. They may even reduce compression via valve and throttle manipulation while the ICE is spinning up to operating rpm to minimize vibration. They ramp the fuel flow up and down to make it easier to smooth.

[acdii]

I noticed that when going down hill (with down hill assist) the ICE spins up and turns into a compressor to help slow it down. The instant is pegged at 60 all white while the battery has the up arrow designating charging.

Edited May 20, 2014 by acdii

[corncobs]

I noticed that when going down hill the ICE spins up and turns into a compressor to help slow it down. The instant is pegged at 60 all white while the battery has the up arrow designating charging.

The ICE is on going downhill without the HVB being full? Interesting I never had that happen I usually hit the downhills assist button to maintain the speed.

[acdii]

 

The ICE is on going downhill without the HVB being full? Interesting I never had that happen I usually hit the downhills assist button to maintain the speed.

I edited my post, That was with the down hill assist on.

[lolder]

It sounds like the down hill assist does automatically what the 2010-12 Gen 1 FFH brake pedal does when the HVB is full.

Edited May 20, 2014 by lolder

[hybridbear]

The ICE is on going downhill without the HVB being full? Interesting I never had that happen I usually hit the downhills assist button to maintain the speed.

If the hill is steep enough that you hit the 35 kW max charging limit of the HVB then the ICE will come on even if the HVB isn't full. I've had this happen a few times and I usually just increase my cruise control speed then to stop the ICE from coming on because I want as much energy as possible to go into the HVB.

[Silver Bullet]

Driving a lot in mountain country I find this discussion most interesting, but I've got some bonehead questions. How do I tell whether my ICE is running or not? What screen configuration should I be watching? I can detect some changes in powertrain noise, but I've no idea what I'm hearing.

I've usually got my cruise control set near the posted speed limit, so accelerating doesn't seem to be much of an option.

Perhaps there's some part of the owner's manual that I need to study more.

[hybridbear]

I now have a PID that allows me to display the 12V battery SOC. As of a couple days ago the 12V SOC was ~47%. Now it's up to 62%. When it was 49% or lower I would see the BS message within 30 seconds of turning off the car. At 60+% I can sit for 45+ seconds without getting the BS message. The DC2DC converter runs at a fairly constant 0.3 kW when there's no load on the battery except having the car on. Adding headlights makes the DC2DC kW increase to 0.5. When the 12V SOC was under 50% the car seemed to be more aggressively charging it because then my DC2DC kW was never less than 0.6 even with no lights/radio/etc drawing power.

 

One new PID that is really cool is "Count of Start Events". This keeps a log of how many times the ICE has started in the Lifetime of the car. With 4700 miles on our car the ICE has turned on about 1150 times so far.

 

For all those concerned about grille blocking and hybrid component temps, you don't need to worry. I have now removed all blocking and the hybrid component temps are warmed now than they ever were in winter. In winter the peak would be right around 140F, with temps rarely exceeding 140F and never for an extended period. Now with ambient temps in the upper 70s, the Generator Inverter, Motor Inverter, Generator Coil & Motor Coil all regularly see temps in excess of 160F with no grille blocking to impede airflow to their radiator. The DC2DC converter temp is also higher now than with grille blocking. It easily reaches 140-150F now without grille blocking.

 

Another neat new PID is the Water Pump RPM. As expected, the ICE water pump is only operational when the ICE is on and it runs 100% of the time that the ICE is on, even when the ICE is cold. In my observations so far its RPM seems tied to ICE RPM/Load. I will investigate this one further.

Edited May 25, 2014 by hybridbear

[lolder]

Is there another pump for the heater core? If not, does the ICE pump run on heater demand when the ICE is off?

[larryh]

For the Fusion Energi, there is a separate pump for the coolant loop that includes the heating element. That pump runs independently of the main coolant loop pump. The main coolant loop pump only runs when the ICE is on. See page 98 of the following document:

 

http://www.motorcraftservice.com/vdirs/diagnostics/pdf/OBDSM1303_HEV.pdf

[larryh]

I have tracked the SOC of the 12 V battery each morning for over a month now for the FFE. The min was 55% and the max was 84%. The average SOC is 69%. I have never seen a battery saver message (except when the car failed to charge the 12 V battery when the car was on and plugged into the charger, but the charger was turned off).

Edited May 25, 2014 by larryh

[hybridbear]

Is there another pump for the heater core? If not, does the ICE pump run on heater demand when the ICE is off?

I don't know. It's getting a little warm to use heat now to be able to check this. The Energi has the ability to isolate the heater core coolant loop and heat it with the electric heater. The Energi must thus have 2 pumps. The Hybrid doesn't isolate the heater core loop, and thus I'd guess that there's only one pump. If we get another cool morning I can check it out.

[hybridbear]

There are multiple sensors that the car uses for ambient air temp. There's one in the PCM and one in the SOBDMC module. There's also another sensor which Torque accesses with its built-in Ambient Air Temp PID. The two custom PID air temp sensors are not the same as the Torque default PID for ambient temp. The Torque one reads much higher than either of the other sensors. None of the sensors match what is displayed by the car to the driver. The temp displayed on the MFT screen was often close to the temp shown by the other PIDs, which are often close but not equal.

The grille shutter PID is the percent open. 0 means completely closed, 100 is completely open. I watched the shutters cycle when first starting the car and the PID changed corresponding to their movement. When the coolant temp exceeds 200F the shutters begin to open. The warmest the coolant got on our city drive yesterday was about 205F, at that point the shutters were about 30% open according to that display. I also saw readings of 4% open, 9% open, 22% open and more.

The 12V battery amps are 0.0 whenever the DC2DC converter is active. No power is drawn from the 12V battery when the car is on. The DC2DC converter rapidly increases or decreases power output as you turn on/off accesories which demand power. The DC2DC converter also charges the 12V battery. On every trip I watch its SOC increase. Its SOC is up to 66% now. I also observe that every time I start the car the 12V SOC is 1+% lower than it was when I shut off the car.

The HVB coolant inlet temp is usually equal or very close to the interior temp. Although, on our drive today the interior temp peaked around 90F and the HVB inlet temp peaked around 83F. The HVB inlet appears to be located somewhere where it gets outside airflow when the windows are open, whereas the sensor for interior temp gets hot even with windows open.

 

It warm summer weather (75+ F) the car does not begin to cool the HVB until it reaches 33 C (91.4 F). In all our driving yesterday the HVB fans were off until the battery reached 91.4 F, then the fans came on to maintain that temperature. After the car was parked and the HVB temp dropped below 90 F, the fans shut off and stayed off.

[Waldo]

There are multiple sensors that the car uses for ambient air temp. There's one in the PCM and one in the SOBDMC module. There's also another sensor which Torque accesses with its built-in Ambient Air Temp PID. The two custom PID air temp sensors are not the same as the Torque default PID for ambient temp. The Torque one reads much higher than either of the other sensors. None of the sensors match what is displayed by the car to the driver. The temp displayed on the MFT screen was often close to the temp shown by the other PIDs, which are often close but not equal.

The temp sensor "in the PCM" is really the traditional ambient temp sensor - the one that's mounted up behind the front bumper. The PCM then passes this signal on to the climate control module, which then "smooths" the signal to display what is actually shown on screen. There is also a temp sensor in the battery air inlet and the interior temp/humidity sensor that the climate uses is the one behind the little grill near the key/push button start.

 

I don't understand what temp your seeing from the SOBDMC module. It could be some arithmetically combined value of the other sensors, but I don't see that it has it's own unique temperature sensor.

[hybridbear]

Today with outside temps 85+ F I saw the highest temps so far for underhood components. The Generator/Motor Inverters both got up to 150-160 F. The Stater Coils in each motor both reached 180 F. The eCVT fluid temp reached 165 F. The DC2DC converter reached 155 F. Even with all these high temps, the car kept the grille shutters closed. This tells me that there is nothing wrong with the 140 F peak temps observed under the hood in the winter with grille blocking.

 

The grille shutters will begin opening slightly when the coolant temp is between 190 & 200 F. The highest my coolant got today was about 209 F. At that point the grille shutters were about 25% open. As the coolant temp dropped while driving in EV mode the shutters closed again.

 

When you turn on the AC and the AC is pulling a lot of power (near 5 kW was the peak I observed today) the grille shutters go to 100% open. As the AC demands lessen, the shutters will begin to close. The minimum shutter opening I observed with the AC on was 40% open. The AC power PID doesn't seem to accurately depict AC power use. Larryh has figured out a formula that should be more accurate that we will be testing.

 

The HVB started out at about 78 F in the morning and quickly reached temps over 90 F. The HVB cooling fans did not turn on until the HVB reached 98.6 F (37 C). From that point forward the HVB fans ran continually at 1200-1600 RPM. The HVB temp continued to rise to 105.8 F (41 C). At that point the HVB cooling fans kept the temp from rising any further, increasing from 1200 RPM to 1600 RPM when the temp reached 107.6 F (42 C) until the temp dropped back to 105.8 F. Once the temp dropped back to 41 C the fan RPM dropped back down to 1200.

 

The 12V battery temp reached as high as 88 F. When I got home and got a couple items out of the trunk I could feel that it was very warm in there (probably about 88 F) and the HVB shelf was very warm.

Edited May 30, 2014 by hybridbear