Mg1 & mg2 temperature???

The grade is the killer but having done similar altitude changes with a full backpack, rifle and Marine drill instructors . . . it will do for 'tall':

• "Old Smokey" - Camp Pendleton
• "Mount M*ther F*cker" - more of a ravine, you used hands and feet to climb it. If you slipped, you didn't stop until you hit the bottom so we had the squad leaders hand off their weapons and go to the rear to 'catch' anyone who was not making it. If we didn't all get to the top, we had to do it over again. I was behind my squad leaders.

The 1971 Infantry Training barracks are long gone but you can see the outline.

Now we live near the edge of the Piedmont Plateau and it ranges from 500-900 ft. So these are all I have to test with. Generally speaking, I do hill climb tests using "Brindley Mountain", the 525 ft. 160M, 8% grade. It equals the energy of the traction battery of our 'original module', NHW11 doing a maximum power climb . . . cresting just as the traction battery energy gives out. The ReInVolt pack goes past the crest without a problem.

Bob Wilson

 

ORNL did a test on the Gen2 and reported 50°C was not exceeded in a mild urban drive cycle, while 60°C was not exceeded in the most demanding drive cycle that the vehicle could track (Pittsburgh cycle).

In pg 31 of the test:

If the Gen2 motors are using Class H, would you expect Gen3 to use a lower class insulation?

Vincent

 

I wish we could find a German or EU driver who might be able to run 160 km/h on the Autoban while recording stator and ICE temperatures. This would pretty well give an upper limit on the operating range. The one value I'm interested in is at what speed the ICE>MG1>MG2 begins to diverge. An ideal test would be stepped speeds:

• 100 km/h in 15 km/h steps to 160 km :: +10 minutes each (assuming level)

Bob Wilson

 

I was just pulling your chain Bob.

 

The test report is available at:
http://k0bg.com/images/pdf/890029.pdf

That is a very thorough interesting test report, however ORNL appears to be speculating on the temperature rating of the Gen2 MG wiring.

I see no evidence that the Gen II used class H insulation. ORNL appears to be assuming that Toyota's warning limits were set to produce nuclear reactor levels of reliability. I seriously doubt that a car company would design an electric motor to survive close to a million miles while running at trouble code generating temperatures.

 

FWIW, with 100% lower grille block on my GenIII, I see temps under 100F for MG1/2 during around town city driving under 15min in duration.

On the freeway temps slowly climb to a max of 178F (MG1) and 160F (MG2) after 50min of driving at 60mph. Inveter coolant temps stays low at 50F-66F.

Ambient Temps were 37F-46F.

Below is an example of a 14 mile freeway drive at 56F ambient temps and 60mph (dashboard) cruise speed. Notice the GPS speed was lower. That is because of the OE 15" tires. The speedo reads high but the odometer is dead on.

 

I just removed all of my grille block. I'll monitor the same systems tomorrow morning and let you know what I see. Weather should be similar enough according to the forecast.

 

Thanks F8L, looking forward to.

 

According to the EVALUATION OF THE 2010 TOYOTA PRIUS
HYBRID SYNERGY DRIVE SYSTEM from: http://ecee.colorado.edu/~ecen5017/notes/OakRidge_2010Prius.pdf

They considered 150C as max limit for windings in gen 3 prius. I find this part interesting (page 70):

 

I removed my grille block and kept a close eye on the relevant systems during his morning's commute. Ambient temp was 37F+-. No wind and dry roads. No heater use. 60mph with CC on.

This shot is at the end of my commute. MG temps were pretty maxed at this point but ICE coolant temp had dropped from a high of 194.8F because of the EV driving for the last leg of the commute.


Temps overall do not appear drastically different from the full lower grille block numbers. Also interesting is that my mpg for the trip was within a few 10ths of what i got yesterday with the full grille block.

My commute profile for reference.

 

Today's result with 100% lower grille block.
Ambient temp was 41F-43F+-. No wind and dry roads. No heater use. 60mph with CC on. Ended the trip at 49.6mpg. Yesterday's trip was 47.2(?)mpg. No change in driving style.

​

 

Thanks for posting. The difference in MG temps is not that great indeed. Some of that could be the slight bump in ambient temp. Let us know if you see a difference with higher speeds or higher ambient temps.

 

Is a safe assumption that grill blocking does nothing more than keep the intake temps higher? What tool are you using to record this data?

 

To an extent that is true but it also keeps coolant temp a little higher when driving at high speeds. If driving at very high speed and/or going up steep hills then grille blocking can raise coolant temp above safe levels despite low ambient temps. So One should still consider their driving conditions and habits before going all out with grille blocking.

Also note that this data is only with lower grille blocking. I have not messed with upper grille blocking.

I'm using the Torque app on my Android phone in conjunction with an ELM bluetooth OBDII adapter plugged into the OBDII port.

 

It's not a big increase but it is there. Under severe loads like 80+mph spped sustained over long periods and/or major inclines I would be cautious. Because the foam grille block is so easy to remove/install I would suggest removing a slat or more on long drives through mountainous areas.

 

The lower grill block also reduces aerodynamic drag. I tested three configurations:

• no block -> baseline
• recessed block - total but conformal with the inner vanes -> ~75% of the lowest drag
• conformal block - total conformal with the outer bumper -> lowest drag, max MPG gain

I'll have to look up my earlier posting but 'F8L' measured MPG improvement is consistent with what I observed.

Bob Wilson

 

I'm in agreement based on my observations although I don't have all of the data to back it up. I've read your posts on the subject though.

Now that I have determined that a full lower grille block is safe for my application, I am going to fabricate a conformal block using coroplast or similar material that I can PlastiDip or paint. The GenIII, 2012 in particular, has a perfect shape for a conformal block!

 

I would bet a large sheet of Kydex would work for the lower grill. It can be heated and formed easily.

 

Bob, Please do repost your earlier results. What Prius needs is reliable, fail-safe automatic shutters. If I'm reading what you said correctly, a recessed shutter would be a worthwhile easiest way to do it from an engineering standpoint. Most bang for the buck too.

 

Or cover with vinyl wrapping