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I thought the board Damien makes was to get the gs450h gearbox to work with the gs450h inverter without the rest of the car around it.
Yes, like other replacement controllers for OEM controller/inverter assemblies.

But as you explain it the board is to use the gs450h inverter and use any motor you want.
While the GS450h inverter could be used with any synchronous AC motor, no one is likely to do that. The reason for using the inverter from a GS450h is that it comes with the motors of a GS450h, is packaged to work with the GS450h transmission, and is electrically suitable for the GS450h.

His board lets you use the GS450H inverter to drive the GS450h transaxle without having the rest of the car.
That's certainly the purpose. :)

... or any other motor.

A motor is agnostic as to what's driving it. Voltage and waveform and it responds accordingly.
While that's possible, to be viable the encoder on the motor must be compatible with the controller's inputs, the voltage, current, and frequency ranges must all be compatible, and all of the tuning parameters must be appropriate to the motor. I'm not sure why anyone would go to the effort of working out this combination for anything but the inverter which the OEM provides with the motor.
 

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While that's possible, to be viable the encoder on the motor must be compatible with the controller's inputs, the voltage, current, and frequency ranges must all be compatible, and all of the tuning parameters must be appropriate to the motor.
Motors aren't that picky.

That's one of the things Damien nags about, that people think you have to have this and that and everything matching. No you don't. Feed it some voltage and it'll be fine. Everything is in roughly the correct range regardless of motor. Control-wise it just takes some tweaking but power-wise it's agnostic.

And there's lots of people using mismatched inverters and drivetrains. More than I've seen used matched one.
 

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Motors aren't that picky.

That's one of the things Damien nags about, that people think you have to have this and that and everything matching. No you don't. Feed it some voltage and it'll be fine. Everything is in roughly the correct range regardless of motor. Control-wise it just takes some tweaking but power-wise it's agnostic.

And there's lots of people using mismatched inverters and drivetrains. More than I've seen used matched one.
In the case of open inverter in general (or any configurable system) - you're correct. However with respect to the 450h setup, the parameters for sync offset, etc, are not available to you as the inverter is unmodified. It is being given the serial commands to drive the 450h transmission. Damien's controller is taking place of the Hybrid Vehicle control unit. I wouldn't consider the 450h inverter to be a general purpose inverter.

For that, the Prius 3rd gen stuff is better.

-Matt
 

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However with respect to the 450h setup, the parameters for sync offset, etc, are not available to you as the inverter is unmodified. It is being given the serial commands to drive the 450h transmission. Damien's controller is taking place of the Hybrid Vehicle control unit. I wouldn't consider the 450h inverter to be a general purpose inverter.
Hmm.

To be honest I haven't looked much at it, as it was the fancier more expensive higher power way to go. I presumed the reverse engineering took a similar path.

On the Prius boards, you yank out their logic board and plug in Damien's in the same place. You replace the brain inside it. It's a hardware replacement of the Prius brain.

What then are the 450H boards? A hardware replacement for the ECU that sends software commands that tell the 450H inverter's brains to operate as normal, but just as the ECU would've instead?
 

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Hmm.

To be honest I haven't looked much at it, as it was the fancier more expensive higher power way to go. I presumed the reverse engineering took a similar path.

On the Prius boards, you yank out their logic board and plug in Damien's in the same place. You replace the brain inside it. It's a hardware replacement of the Prius brain.

What then are the 450H boards? A hardware replacement for the ECU that sends software commands that tell the 450H inverter's brains to operate as normal, but just as the ECU would've instead?
Exactly. The Prius board you have complete control over the hardware. On the 450h it replaces the stock ECU, yes.

-Matt
 

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I should've known the answer to this, as I've built one...

The Prius Gen 3 inverter has a logic board inside it that can be replaced with a custom one.

The Prius Gen 2 inverter just has a 40-pin connector and a cable that runs to, I dunno, some ECU or some inverter brains or I'm not sure what. But the replacement board is very, very simple. There's more complexity in what accessory wires you need to connect to it (throttle pedal, brake signal, etc) than there is that connect to further inverter guts. 3 drive signals (1 for each phase), 2 wires to tell it not to shut down, +-12vdc, and a pin so it knows the capacitor voltage. That's it.

There's clearly some brains below the Gen2, because it still has all kinds of intelligence in order to not let you do stupid things, turn phases on at the same time, overvolt, over current, overheat, etc. But that must be deeper in the bowels. You tell the phases what to do and it otherwise obeys.

The GS450H I'm not sure about. Is it like the Prius Gen2, replacing what comes in from the wiring harness, or is it fancier than that?
 

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A couple of additional questions about this whole setup:

While Damien made it very clear that this hybrid transmission, since it originally was intended to have a gas V6 in front of it, can handle quite a bit of power going through it to the output flange I am interested in the overall lifespan of the two motors themselves when tuned for higher output. The strength of the internal rotating parts of the transmission itself is not in question, then.

He has also been very clear that it is not required to run its motors up to the maximum of 650V that it was designed to handle (in very short bursts in a stock GS450h).

His last posted testing voltage was at 360V with noted sag in the battery he was using and at that level he was outputting around 120kW or about 160hp. And for many potential applications that is pretty good.

So what I am wondering is... thinking on what the MG1 and MG2 motors themselves can endure 24/7... if a much more uprated battery setup were used (I won't get into the weight or packaging constraints at this moment) with open-inverter parameters allowing for a modest regular all-day daily driveable baseline of 150kW (about 200hp) or even 190kW (around 250hp)... does it stand to reason that the MG1 and MG2 motors themselves will be able to hold reliably at that current and voltage level on a regular basis?

I think I read somewhere that the theoretical maximum output for this system might be 270hp or so but just sticking to achieving a regular output of 200hp or 250hp would that be asking too much such that the two motors would burn out very prematurely or might anywhere between the total all-day-long output of between 150-190kW (if you ask the motor to draw that much current at any given time) still be considered reliable?

I know that when cruising along especially if the motors are not revving exceptionally high there will not be close to the total current draw on them as far as they will be tuned.

I'm just trying to get an idea of whether or not this system can handle power in that range for a larger car without potentially harming and drastically shortening the life of the MG1 and MG2 motors.
 

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Any comparison of ratings for motors or engines is all about rating conditions. Industrial motors are rated for continuous operation, so in intermittent service they can be run at much higher than their rated power. Neither electric motors nor engines in automotive applications are expected to run at their rated power for more than a few seconds at a time.

It is completely inappropriate to take a random power rating for an electric motor and assume due to some magic superiority of electric motors that it can be reasonably used at much higher power, even though motors from some specific applications with low ratings may run successfully at much higher power, in different conditions and usually with different controllers.
 

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So what I am wondering is... thinking on what the MG1 and MG2 motors themselves can endure 24/7... if a much more uprated battery setup were used (I won't get into the weight or packaging constraints at this moment) with open-inverter parameters allowing for a modest regular all-day daily driveable baseline of 150kW (about 200hp) or even 190kW (around 250hp)... does it stand to reason that the MG1 and MG2 motors themselves will be able to hold reliably at that current and voltage level on a regular basis??
In EV mode, only MG2 is driving the vehicle, and performance is very limited compared to hybrid (engine running) operation. In normal (engine running) mode, most of the engine output is flowing through the power splitter gearset and to the output without using either motor-generator; in parallel, some power is flowing through the power splitter gearset to MG1 and then electrically to MG2, or to MG2 and then electrically to MG1 and out through the power splitter gearset (depending on the combination of road speed and engine speed). This split power flow is integral to the way the HSD works, and is important to its efficiency (because it routes substantial power through a fully mechanical path instead of a much less efficient generator-motor pair). The result is that the amount of engine power handled by the transmission system doesn't indicate the amount of power which the motors can produce by themselves.

This is not a series hybrid system - it is not even capable of operating in series mode (unlike some other hybrids). In a purely series hybrid design (BMW i3, Nissan e-Power) you can assume that as a battery-only EV the same power can be sustained by the drive motor as with the engine... but again, the Toyota system is not a series hybrid.
 

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While Damien made it very clear that this hybrid transmission, since it originally was intended to have a gas V6 in front of it, can handle quite a bit of power going through it to the output flange I am interested in the overall lifespan of the two motors themselves when tuned for higher output.* The strength of the internal rotating parts of the transmission itself is not in question, then..
The same transmission was used in the XF40 generation Lexus LS 600h, which had a 394 HP 5.0L V8. I agree... although that only means that the two-speed planetary gear set on the output can handle lots of power, the power splitter isn't an issue either. The total system output rating says nothing about the gear sets which link MG1 and MG2 to the other components, but I would guess that they'll be fine, too.

So what*I am wondering is... thinking on what the MG1 and MG2 motors themselves can endure 24/7...
I'm just trying to get an idea of whether or not this system can handle power in that range for a larger car without potentially harming and drastically shortening the life of the MG1 and MG2 motors.
The likely durability issue would be related to excessive heat. As long as the motors are operated within the peak voltage and peak current for which they are designed (even though they wouldn't normally see those peaks simultaneously), the concern would be cooling. The unit has cooling capacity for the worst conditions expected in the intended application, not continuous high-power operation, particularly of both motor-generators at the same time.
Years ago there were discussions of using the Highlander Hybrid's rear drive unit as the only drive unit for a DIY EV, and it was quickly realized that it has enough power for many projects (even without driving it past it's Toyota-rated output), but it can only sustain that briefly before overheating. It is intended to briefly drive only when the Highlander's front tires slip; if it were intended to drive continuously it would have better cooling.

Any the test of what components can handle needs to answer the question "for how long"? Many builders do some interesting stuff, but the entire operating life of one of their projects (before they abandon it, or tear it apart and go on to something else) probably wouldn't compare to a single testing day at any auto manufacturer, and almost no FIY builder uses even a small fraction of the test instrumentation that a serious test would require.
 

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A key feature of the design of Toyota's Hybrid Synergy Drive is that it only works as a power-split system, so it is unable to transmit engine power to the output without the electric motor-generators. Similarly, MG1 is unable to drive the vehicle at all without the engine working; however, while the HSD cannot transmit power without MG1, not all of the power goes through MG1 and MG2.

For a reasonableness check, consider that as limited by the stock controls the total of MG1 and MG2 output is much less than the engine output, and the car clearly demonstrates greater performance than that total MG output could produce. Why? Because much of the engine's power is mechanically transmitted, not going through the motor-generators.

For those interested in how Toyota's hybrid system works, and unwilling to look up any of the many online descriptions:
  • the engine and MG1 are connected to the two input sides of a planetary power splitter gearset, which works like having the engine and MG1 connected to the right and left axles coming from a conventional differential (the speed of the driveshaft is proportional to the average of the left and right axle speeds)
  • the "driveshaft" side of the power splitter is connected to the transmission's output
  • MG2 is connected to the transmission's output with fixed-ratio gearing
  • the speed of MG1 relative to the output determines the engine speed (run MG1 faster and the engine must run slower so that their average still corresponds to the road speed)
  • electrical power produced or used by MG1 to hit that target speed goes to or comes from MG2
  • when the engine is not running, only MG2 drives (or regeneratively brakes) the vehicle

GM's two-mode hybrid (also used by Chrysler and BMW), including the Volt's Voltec system, and various other hybrids (such as most Ford systems) are more complex variations of this power-split approach.
 

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Yup, about 1kWh/mile if I recall correctly.
Just about everything you're saying is wrong, or bizarrely out of context.

Like, this statement here. Why are you talking about it's mileage in response to his question? His question had nothing to do with kWh/mile.

It has L O N G been understood that while mathematically 0.745Kw ~ 1 HP, in practical applications it does not work out that way. Electric motors play WAY above their nameplates.
No, not true. Their nameplates are rated for their circumstances. Look at a 1hp blender vs. a 1hp industrial pump motor. Completely different scales and context behind the ratings.

The math holds up.

The context of the ratings, in different context, would change the ratings.

you get no driving power without the efforts of MG1 & MG2. It has been proven in the Gen 2 Prius and with the 450H.
Technically true, but contextually false. It doesn't help answer Cinephile's questions.

...


Cinephile said:
does it stand to reason that the MG1 and MG2 motors themselves will be able to hold reliably at that current and voltage level on a regular basis?
Super simple answer to that. There are temperature sensors on the motors. If they overheat, Toyota will tell the inverter to take it easy.

Graceful failing is something Toyota electronics do quite well.

That said, the lifespan of the insulation on the wires is rated for a certain temperature. I think it's something like 20,000 hours at the rated temp (keep in mind 2,000 hours is a 9-5 work-year, so, even if you drove professionally, 8 hours a day [how would you do that, in an electric car, at max temp, without running out of battery?] all at the max temperature for the insulation, that's still 10 years of lifespan). Above which faster-than-linearly degrades its lifespan.

I think I read somewhere that the theoretical maximum output for this system might be 270hp
Ahh hell, way more. The Prius Gen 3 inverter has been tested to handle 433hp just on MG2 alone. If the same ratio is true of the Gen 3 as the Gen 2, it should be able to handle 680hp.

And the GS450H is a heavier duty inverter than the Prius Gen 3.

Gearbox-wise, I don't see why it would be any different. The limitation is cooling and for how long it can be sustained.

Damien's never tested a car at full voltage full throttle. Just lack of battery pack. He threw in some junky cells at lower voltage and he still shot up to highway speed easily. What more does a vehicle need?

I'm just trying to get an idea of whether or not this system can handle power in that range for a larger car without potentially harming and drastically shortening the life of the MG1 and MG2 motors.
The answer to whether it can handle the power, is whether it has aggressive enough coolant, and aggressive enough cooling.

Otherwise it's an AC motor, it'll live forever.

Say you're using 200kw. On, what, a 50kwh pack? A giant 100kwh pack? That's 15-30 minutes before you run out of energy. You'll run out of ability to abuse the motors long enough for it to matter.

Outside of a racing conditions (or, maybe, towing a motorhome up a hill?), how would you ever drive fast enough to even sustain that kind of power draw? Soon as you're at highway speed your power requirements are back to like, 20-30hp max.
 
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