Hot-rodding the Toyota MGR

[4x4EV]

thingstodo-- i have 3 mgr's saved in my ebay shopping cart, ranging from 450-750 after shipping, i ended up searching the serial number, i will be purchasing one at the end of this month for testing with the ac control board from paul when i get my school funding so i know they are out there

06 07 08 09 10 11 12 Highlander Engine Hybrid Elec RR 4WD 300279 | eBay

[thingstodo]

Originally Posted by e*clipse

Regarding motor testing, I've got a few limitations. The first one is I don't have a 50kW dino.

I don't either .. I'm trying to come up with a mechanical setup that will allow two of them to be tied together with belts. Nothing complicated has worked on paper. The simplest would have each MGR equipped with two axles, bearings and mounts, like it's going into a truck. Mount the wheel bearings the correct distance apart, add rims and tires. The tires with almost no pressure so the belt rides within the rim. One will work as motor, the other as generator. So you'd need 2 MGRs and 2 controllers, but the same battery bank should work. This is a tried and true method for putting a load on single motors - couple them together and use a controller for each - never seen it down with a system that includes gearbox and differential.

I know we have belts (they are called powerbands) at my day job that can handle 400 HP but they are not cheap. Sometimes the belts are replaced during a maintenance day, before they are really worn down ... perhaps I can get a gate pass?

Another thought - would running the motor at full power for 60 seconds be worthwhile for a car?

Nope. The 60 seconds is to see whether we are overloading it. If you want to stick to 10 seconds, or 12, or 15 that wold be good as well. It SHOULD be more pronounced and easier to see at 60 seconds.

Would it be possible to test the current-handling capability - not the power - of the stator windings at, say 12V? or perhaps use 120VAC to calculate an RMS AC type power??

Will 12V give you useful numbers? With the phasing tricks that you have already discussed to counter the large back-emf produced by the motor, you'd need to run very slowly to make 12V drive a load. Plus if the motors are not loaded, it will be tough to push much current through.

I guess you could bolt them to your test bench and run your test at STALL. With an AC induction motor, that will give you 6X to 8X full load amps, but that is kinda dependent on the slip. With a PM motor there is no slip so would you just be putting pulses, almost like DC, to one set of coils, like a servo, trying to rotate it?? The switched reluctance .. would maybe work that way too? Set up the magnetic field to make the rotor want to rotate and align the magnetic lines of flux?

I have no experience in this - just thinking out loud.

Once you get into the 120VAC range, you have reached 20% of the rated voltage so I would expect 20% of the current - 10 kw - hard to generate without a controller.

Perhaps if you had a 12V battery charger, one of those booster types that will put out like 200A for a few seconds to start up a car. That is done with a transformer inside, so you may be able to get to the 12VAC before it gets rectified with diodes. If you were to connect that to the MGR, with a contactor/starter ... you could measure one phase with a clamp-on meter during start, and if you figure out how to put a load onto the axles (but it would need to be both axles?) you could watch the current rise .. until you melted the battery charger. But the voltage is low, so 60 Hz may not be slow enough to do a decent current test?

Lots of unknowns on this one.

[thingstodo]

Originally Posted by 4x4EV

thingstodo-- i have 3 mgr's saved in my ebay shopping cart, ranging from 450-750 after shipping, i ended up searching the serial number, i will be purchasing one at the end of this month for testing with the ac control board from paul when i get my school funding so i know they are out there

06 07 08 09 10 11 12 Highlander Engine Hybrid Elec RR 4WD 300279 | eBay

Thanks for the link.

I don't understand searching ebay by the serial number ... do you mean part number?

Lots of vendors do not ship to Canada, or ship here once in a while. The hassle getting anything across the border is not my favorite obstacle course .. I was hoping that someone in Canada was selling these on ebay

I just modified my salvage parts search to 'carrier' for RX400 and RX450 - the search has no results, but it accepted 'carrier'. I'll keep trying.

[4x4EV]

yes by part number, my bad

I believe that link does ship anywhere in the americas


Interchange Part Number:
300-65002

[freebeard]

"It may not look like much, old man; but it did the Kessel run in 12 Parsecs."


Dropped in place and wedged until it's almost level. It needs to move forward about 1" and maybe be rotated up in the front to conform to the rise in the frame rails; but there's a good 1 1/2" clearance to the sheetmetal overhead. Now it's back downtown for pressure washing and steam cleaning. The temp sensor plug came with it.

I'm stoked. Not having to modify the original sheetmetal opens up Bu$ine$$ Opportunitie$.

Dynamometer: Bolt sprockets to both output shafts and run chains to two sprockets on a single axle.

[e*clipse]

Thank you for the thoughtful post.
I need to mull things over, I'll get back later.

- E*clipse

Originally Posted by thingstodo

I don't either .. I'm trying to come up with a mechanical setup that will allow two of them to be tied together with belts. Nothing complicated has worked on paper. The simplest would have each MGR equipped with two axles, bearings and mounts, like it's going into a truck. Mount the wheel bearings the correct distance apart, add rims and tires. The tires with almost no pressure so the belt rides within the rim. One will work as motor, the other as generator. So you'd need 2 MGRs and 2 controllers, but the same battery bank should work. This is a tried and true method for putting a load on single motors - couple them together and use a controller for each - never seen it down with a system that includes gearbox and differential.

I know we have belts (they are called powerbands) at my day job that can handle 400 HP but they are not cheap. Sometimes the belts are replaced during a maintenance day, before they are really worn down ... perhaps I can get a gate pass?



Nope. The 60 seconds is to see whether we are overloading it. If you want to stick to 10 seconds, or 12, or 15 that wold be good as well. It SHOULD be more pronounced and easier to see at 60 seconds.



Will 12V give you useful numbers? With the phasing tricks that you have already discussed to counter the large back-emf produced by the motor, you'd need to run very slowly to make 12V drive a load. Plus if the motors are not loaded, it will be tough to push much current through.

I guess you could bolt them to your test bench and run your test at STALL. With an AC induction motor, that will give you 6X to 8X full load amps, but that is kinda dependent on the slip. With a PM motor there is no slip so would you just be putting pulses, almost like DC, to one set of coils, like a servo, trying to rotate it?? The switched reluctance .. would maybe work that way too? Set up the magnetic field to make the rotor want to rotate and align the magnetic lines of flux?

I have no experience in this - just thinking out loud.

Once you get into the 120VAC range, you have reached 20% of the rated voltage so I would expect 20% of the current - 10 kw - hard to generate without a controller.

Perhaps if you had a 12V battery charger, one of those booster types that will put out like 200A for a few seconds to start up a car. That is done with a transformer inside, so you may be able to get to the 12VAC before it gets rectified with diodes. If you were to connect that to the MGR, with a contactor/starter ... you could measure one phase with a clamp-on meter during start, and if you figure out how to put a load onto the axles (but it would need to be both axles?) you could watch the current rise .. until you melted the battery charger. But the voltage is low, so 60 Hz may not be slow enough to do a decent current test?

Lots of unknowns on this one.

[e*clipse]

"It may not look like much, old man; but it did the Kessel run in 12 Parsecs"

It looks like it fits very nicely. I would probably rotate it backward until the bottom is level-ish. I think that will also make things fit better as you said, relative to the frame rails. A decent indicator is those two back bolt-holes. Those holes should be parallel to the ground.

- E*clipse

Originally Posted by freebeard

"It may not look like much, old man; but it did the Kessel run in 12 Parsecs."


Dropped in place and wedged until it's almost level. It needs to move forward about 1" and maybe be rotated up in the front to conform to the rise in the frame rails; but there's a good 1 1/2" clearance to the sheetmetal overhead. Now it's back downtown for pressure washing and steam cleaning. The temp sensor plug came with it.

I'm stoked. Not having to modify the original sheetmetal opens up Bu$ine$$ Opportunitie$.

Dynamometer: Bolt sprockets to both output shafts and run chains to two sprockets on a single axle.

[freebeard]

I had to see what I could do immediately. I had to crawl over a pile of lumber to take the pictures. Next week when space opens up in the barn, it'll go up on jack stands with the wheels off. Those boxed trailing arms have to go, too. So I'll have lots of elbow room and a concrete floor to work on.

The rear mounting holes are in plane with the holes in the frame end. The wider-spaced front mounting hole will fall about half-way between the forward transaxle mount and the top shock absorber mounts. Compare to a truss bar:



For now, I prepping to go to the Salt Flats this weekend.

[thingstodo]

Originally Posted by freebeard

Dynamometer: Bolt sprockets to both output shafts and run chains to two sprockets on a single axle.

*MUCH* simpler than what I was thinking. I LIKE IT!

I think I'd still use 2 MGRs and 2 controllers if I had the choice, with the sprockets and the chains.

[e*clipse]

With a dyno, we still need a HUGE load dump. Pump water? Heat water?

One thought I had was to just build the car in my case with just the front motor. Build the controller so is could supply about 50% more than the rated power ( 75 kW?? ) Measure everything really well, and go do some slow drag races. F=ma. Step the controller's power limit up each run, and allow a LONG cool-down time.

I know that's no help for ***engineering*** stuff, but it would help for my multiple motor design.

Would knowing the stator winding be any help? Back at post #12 I showed some pics of the stator windings. Each phase is a bundle of 12 wires the measure 0.032" OD. (measured with Brown & Sharp calipers) I have no idea what the insulation thickness is.

Knowing the winding diameter gives some interesting information:
American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies and wire breaking strength
for 0.032, AWG20 wire: 10.15Ohms/1000ft 11A max chassis 1.5A max power 27 kHz
for 0.0285, AWG21 wire: 12.8Ohms/1000ft 9A max chassis 1.2A max power 33 kHz

I'm assuming "power" wiring is continuous, "chassis" wiring is for short-term bursts. I'm assuming for motor use, they're using someplace in between because these wires are bundled and can't dissipate heat like a single strand.

So, using the AWG 21 #'s, 12 strands * 9A = 108A.

It's also unlikely that a Japanese company is using AWG wire. The size is VERY close to 0.75mm.

Has anyone compared motor current limits or power ratings to the winding diameters? ***HEY*** Those ORNL papers might have something about this. They did push them harder than spec in the tests with a real dyno.