I don't know where you got your Warp 11 numbers but they don't make sense... nothing beats good old - fashioned DC series for torque! How many apps to get that number?
Sent from my SM-T380 using Tapatalk
Sent from my SM-T380 using Tapatalk
transmission less conversion
Hi
Has anyone done a motor direct connect to driveshaft conversion? What adapters or solutions did you come up with, or anyone know of any examples? I need to go directly from the motor to the driveshaft. Any help be appreciated.
Thanks
Has anyone done a motor direct connect to driveshaft conversion? What adapters or solutions did you come up with, or anyone know of any examples? I need to go directly from the motor to the driveshaft. Any help be appreciated.
Thanks
41 - 60 of 63 Posts
I don't use the original gearbox because that's what creates up roughly half the loss in rated horse-power in the original setup plus it's an awkward thing to convert into. It would need add'l hydraulic plumbing, a modulated vacuum line, a kick-down <something>, a lot of parts & pieces.@rob
do you have a gearbox and differential? don't forget about the torque multiplication of those gears.
In 3rd gear the original gear-box becomes a flat 1:1, so no more multiplier. That's how I figured the matching, at 65 mph (say) so as minimal-reduction as it gets. When pulling away the engine never got much above 1/2-2/3 of max, and per the engine rpm<>ft.lbs curve it still works out OK, but that part (losing the add'l multiplier of 1st gear) is a worry until it all proves out.
I do still use the original differential, but it's a same-same i.e. that was there on the original too, so for the direct engine<>motor matching exercise I ignored it.
I use the numbers from www.EVwest.com and a couple others like it. The guys at EVwest have been solid so far but it could all be totally wrong, I have no way of telling?I don't know where you got your Warp 11 numbers but they don't make sense... nothing beats good old - fashioned DC series for torque! How many apps to get that number?
Sent from my SM-T380 using Tapatalk
Their web-site quotes the Warp-11 as (and I'm copy-pasting here):
Rated Torque: 173 Lb Ft @ 72 Volts And 597 Amps (1442 RPM)
Rated Power: 58 HP @ @ 72 Volts And 597 Amps (1442 RPM)
The volt/amp > HP math is right, so I'm trusting the ft/lbs number?
By comparison, they quote the AC azure motor as have bench tested to 160HP and 221 ft lbs of torque at 300V and 400A.. Same thing, the Volt/Amp > bhp math is right, and it looks right?
All in all, this (to me) said I'd get way better bhp but lower torque per kW going with the Azures vd the Warp-11's. The reduction gear makes up for the torque "loss", so as a package it sounded OK. The weight of the car says I do need the bhp (at 65 mph) and I have the extra torque covered, so it all seemed to line up? On paper anyway? I guess I'll find out.
@Duncan:
Sure, I have wimpy motors, and maybe I just got things backwards. I can still flip to something else (I can always Ebay the parts and come out even/ahead), so I'll ask:
- what's the model of the Hitachi motor(s)? I can't find one that is more than maybe 15-20 kW at 3000+ rpm between Ebay, Craigslist etc without getting some humongous grey dead-weight. I can call the local Hitachi dealer but for that a part-number would seriously help...
- what's the car?
I'm asking because I am stuck figuring out my cooling and with your Amp & Voltage numbers you're a ways ahead of me.
My battery is 340V and 100 kWh, but I won't know the running amps until I get this thing to 65 mph. What do you see for amps going up-hill & down-hill at say 65 mph, and what kind of setup do you run to keep it all from overheating? Do you cool the batteries? The controller? The motor? Where is the majority of the heat coming from?
I know, it's a lot of questions, but it sounds like you've figured stuff out I haven't yet...
Sure, I have wimpy motors, and maybe I just got things backwards. I can still flip to something else (I can always Ebay the parts and come out even/ahead), so I'll ask:
- what's the model of the Hitachi motor(s)? I can't find one that is more than maybe 15-20 kW at 3000+ rpm between Ebay, Craigslist etc without getting some humongous grey dead-weight. I can call the local Hitachi dealer but for that a part-number would seriously help...
- what's the car?
I'm asking because I am stuck figuring out my cooling and with your Amp & Voltage numbers you're a ways ahead of me.
My battery is 340V and 100 kWh, but I won't know the running amps until I get this thing to 65 mph. What do you see for amps going up-hill & down-hill at say 65 mph, and what kind of setup do you run to keep it all from overheating? Do you cool the batteries? The controller? The motor? Where is the majority of the heat coming from?
I know, it's a lot of questions, but it sounds like you've figured stuff out I haven't yet...
The idea that DC is much cheaper is based primarily on the assumption that DC means a salvaged motor such as from a forklift, while an AC motor will be new. There is also a likely difference in controller cost, since a DC controller is simpler than an inverter. This sort of generalization is useless and confusing.AC or DC is hardly the point. Also, I just looked and a 70 bhp AC motor is $2,900 and a 58 bhp DC motor (warp 11) is $3,200. Close enough that no-one is a LOT cheaper.
Low-voltage aftermarket AC motors for industrial equipment, sold to DIY EV converters, are relatively wimpy and expensive. High-performance high-voltage AC motors (such as the BorgWarner and YASA products) are available and comparable to OEM motors, but very expensive. Overly broad categories don't help, and cause confusion.Aftermarket AC motors are wimpy and expensive
If you're going with the "cheap DC" approach, forget model numbers. The general method appears to be to find someone scrapping forklifts, and buy the biggest rotating hunk of iron and copper you can find. It is then operated at much higher voltage and current than intended, so nothing about the original ratings apply and manufacturers specs don't tell you much.@- what's the model of the Hitachi motor(s)? I can't find one that is more than maybe 15-20 kW at 3000+ rpm between Ebay, Craigslist etc without getting some humongous grey dead-weight. I can call the local Hitachi dealer but for that a part-number would seriously help..
So i'm thinking either doing the Transwarp tail housing or doing the sliding driveshaft. I'm not even sure they sell the tail house separately
Even if NetGain sold the housing separately, it wouldn't do you any good if your motor doesn't have the same extended shaft with splined end as a TransWarP motor.
I can't really ever get a solid answer about why that is.Low-voltage aftermarket AC motors for industrial equipment, sold to DIY EV converters, are relatively wimpy and expensive.
Yeah, if you run them at rated voltage, they'll be wimpy. But so are DC forklift motors until you overvolt them.
What's the difference between an overvolted AC motor and something more purpose built for EV use? I can't think of many differences, even fewer than on DC motors.
Hi rob kr
This is my car
https://www.diyelectriccar.com/foru...dubious-device-44370p15.html?highlight=duncan
Not at all sure it's an example of what to do but it is great fun
Matt
The problem is that a DC motor controller is easy and you can very simply over amp and over volt them
AC motor controllers are much much more difficult and you can't just slap something together and go
This is my car
https://www.diyelectriccar.com/foru...dubious-device-44370p15.html?highlight=duncan
Not at all sure it's an example of what to do but it is great fun
Matt
The problem is that a DC motor controller is easy and you can very simply over amp and over volt them
AC motor controllers are much much more difficult and you can't just slap something together and go
Other than the difficulty of tuning your parameters... any reason I shouldn't be able to pull as much power from an AC?The problem is that a DC motor controller is easy and you can very simply over amp and over volt them
AC motor controllers are much much more difficult and you can't just slap something together and go
Like, I think about my 265 lb AC forklift motor, and compare it to what's in a Tesla (which has a gearbox added to it), and the Tesla large rear motor is like, 15-20x the power, for 1/3 the weight (before gearbox and inverter). That's... 45-60x as power dense.
So, other than just adding more voltage than it was designed for, and maybe spinning it faster than it was designed for, can it be comparable?
Hi Matt
Two engineers - Tesla and Forklift
The Tesla guy has low weight and power as absolute goals
The Forklift guy does NOT
If he designs a light motor then they need more weights and people will look at it and snear
Same with power
Saying that I AM getting a LOT more power out of my Hitachi motor - but I don't expect to get 200,000 miles out of it
Two engineers - Tesla and Forklift
The Tesla guy has low weight and power as absolute goals
The Forklift guy does NOT
If he designs a light motor then they need more weights and people will look at it and snear
Same with power
Saying that I AM getting a LOT more power out of my Hitachi motor - but I don't expect to get 200,000 miles out of it
One difference that seems to be fairly common is that, if they have any cooling at all, industrial AC motors are cooled by a fan on the motor shaft, whereas high-performance AC motors that are purpose-built for use in EVs are fluid-cooled.What's the difference between an overvolted AC motor and something more purpose built for EV use? I can't think of many differences, even fewer than on DC motors.
Industrial AC motor notes
Most industrial AC motors (3-phase, ~480vac, 50 or 60Hz) are wound with lots of turns of small gage wire in the necessary pole pattern to achieve the desired speed of operation e.g. 3600, 1800, 1200 for 2,4,6 pole motors. This provides an inductance and resistance that can handle the frequency and currents associated with the 480vac supply voltage. Note that this winding will have a quite high back emf (voltage generated by the rotor in motion) also.
In order to operate one of these from a DC power source would require about 680 VDC just to match the performance as if running from the AC mains. That is way higher than anybody's pack voltage and only gets you to 3600 rpm max for a 2-pole motor. There is no over-volting such an AC motor to run faster--adding more voltage does not get you higher rpm, even if you could build a pack above 680 VDC.
To get the torque and speed needed for EVs requires a different winding with a pole count and inductance suitable for the frequency range, and with a wire gage that can handle the current at a lower supply voltage typical of EVs, e.g. OEMs ~360-400VDC. Then you need a controller or motor inverter than can produce 3-phase currents at much higher than 60 Hz.
Most industrial AC motors (3-phase, ~480vac, 50 or 60Hz) are wound with lots of turns of small gage wire in the necessary pole pattern to achieve the desired speed of operation e.g. 3600, 1800, 1200 for 2,4,6 pole motors. This provides an inductance and resistance that can handle the frequency and currents associated with the 480vac supply voltage. Note that this winding will have a quite high back emf (voltage generated by the rotor in motion) also.
In order to operate one of these from a DC power source would require about 680 VDC just to match the performance as if running from the AC mains. That is way higher than anybody's pack voltage and only gets you to 3600 rpm max for a 2-pole motor. There is no over-volting such an AC motor to run faster--adding more voltage does not get you higher rpm, even if you could build a pack above 680 VDC.
To get the torque and speed needed for EVs requires a different winding with a pole count and inductance suitable for the frequency range, and with a wire gage that can handle the current at a lower supply voltage typical of EVs, e.g. OEMs ~360-400VDC. Then you need a controller or motor inverter than can produce 3-phase currents at much higher than 60 Hz.
Re: Industrial AC motor notes
An EV running typical production voltage (360 V, nominally) can drive these motors at much higher than 120 VAC.
But running faster certainly does require more voltage, as with any motor.
Yes, windings must be appropriate for the current which will be required, but that is true of DC motors as well. This returns us to the question of whether aftermarket EV AC motors (such as the "AC-" product line of HPEVS) can be pushed harder than their ratings (driving them at higher current and higher frequency, both requiring higher voltage)... and if not, why not?
I don't think the question which Matt raised was about pushing a 480 VAC industrial motor. The discussion was comparing brushed DC motors (which can be pushed from their 48 V ratings in forklifts and up to 120 V ratings as aftermarket items) to similarly sized induction motors (can they be pushed from their up to 120 V ratings?)Most industrial AC motors (3-phase, ~480vac, 50 or 60Hz) are wound with lots of turns of small gage wire in the necessary pole pattern to achieve the desired speed of operation e.g. 3600, 1800, 1200 for 2,4,6 pole motors.
...
In order to operate one of these from a DC power source would require about 680 VDC just to match the performance as if running from the AC mains. That is way higher than anybody's pack voltage and only gets you to 3600 rpm max for a 2-pole motor.
An EV running typical production voltage (360 V, nominally) can drive these motors at much higher than 120 VAC.
It is true that just adding more voltage does not change speed; in any AC motor, speed is determined by power supply frequency, given enough voltage to drive enough current to produce enough torque to keep the motor in synch (in the case of synchronous motors) or at an appropriate level of slip (in the case of induction motors).There is no over-volting such an AC motor to run faster--adding more voltage does not get you higher rpm, even if you could build a pack above 680 VDC.
But running faster certainly does require more voltage, as with any motor.
The inverter frequency is not a problem. Of course any AC EV needs a variable-frequency inverter, and there's nothing special about 60 Hz; for instance, 6000 rpm in a 4-pole motor needs 200 Hz... and that's only midway up the speed range for a typical production EV. Production EVs can have much higher pole counts (a Leaf motor is apparently 8-pole and a BorgWarner HVH 250-series is 10-pole), so they run higher inverter output frequencies.To get the torque and speed needed for EVs requires a different winding with a pole count and inductance suitable for the frequency range, and with a wire gage that can handle the current at a lower supply voltage typical of EVs, e.g. OEMs ~360-400VDC. Then you need a controller or motor inverter than can produce 3-phase currents at much higher than 60 Hz.
Yes, windings must be appropriate for the current which will be required, but that is true of DC motors as well. This returns us to the question of whether aftermarket EV AC motors (such as the "AC-" product line of HPEVS) can be pushed harder than their ratings (driving them at higher current and higher frequency, both requiring higher voltage)... and if not, why not?
Im somewhat little informed on this but Im looking to find a taper lock bushing with the bolt on hub all in a set. Im in the USA so does anyone know companies that sell them as a set? I have an 1 1/8th shaft on my motor. Im just trying to leave the guess work out of it, if any of you know where to get?
Thanks
Thanks
You can use a weld-on hub, and weld on and machine a flange to fit your application: http://www.linngear.com/part-type/type-w/
Or you can machine a taper-lock chain sprocket. The chain sprocket can be a used, worn-out one because you'll most likely machine away the teeth: http://www.linngear.com/part-type/taper-lock/
Other suppliers are Dodge, Browning,and Martin.
Or you can machine a taper-lock chain sprocket. The chain sprocket can be a used, worn-out one because you'll most likely machine away the teeth: http://www.linngear.com/part-type/taper-lock/
Other suppliers are Dodge, Browning,and Martin.
Re: Industrial AC motor notes
I missed this set of replies earlier, oops.
I wiggled in my own use case, which isn't a 3ph mains ACIM, but an ACIM (4 pole) from a forklift, designed for 48v. It's almost certainly going to have thicker wires than one designed to run off the grid. So, hopefully it's going to be suitably wound for EV repurposing.
I don't know that I've actually seen anyone with an EV build that uses an AC forklift motor yet, which is why I'm both hesitant (is there a reason this won't work and why everyone has chosen differently so far?) and curious.
I missed this set of replies earlier, oops.
Ahh. Gotcha. I was somewhat hijacking an earlier comment about industrial 3ph motors, so, that answers that question.Most industrial AC motors (3-phase, ~480vac, 50 or 60Hz) are wound with lots of turns of small gage wire in the necessary pole pattern to achieve the desired speed of operation e.g. 3600, 1800, 1200 for 2,4,6 pole motors.
I wiggled in my own use case, which isn't a 3ph mains ACIM, but an ACIM (4 pole) from a forklift, designed for 48v. It's almost certainly going to have thicker wires than one designed to run off the grid. So, hopefully it's going to be suitably wound for EV repurposing.
I don't know that I've actually seen anyone with an EV build that uses an AC forklift motor yet, which is why I'm both hesitant (is there a reason this won't work and why everyone has chosen differently so far?) and curious.
Depends whether it is made for 3-phase or single (split) phase power at 48vac, plus the power or torque rating. Also with 4 poles it runs at 1800 rpm with 60 Hz current, 3600 @ 120 Hz, etc., so how much gearing will be a factor also to determine if it is suitable for an EV on the highway.
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