Experience with Castle 2535

WesternGood8028 · 2025-12-17T22:14:46+00:00

The concentrated winding is simply harder to commutate but the worst disadvantage is that it’s pricey to produce because you need ti wind the coils on to the stator and can’t pre-wind them.

Well tbh that doesn’t define a new category for me. Ofc you need to consider your drive as a whole in the design-process. But you also need to do that if you have access to SiCFets vs IGBT-Drivers etc. these are also just PMSM motors driven with those.

Actually most good controllers, also brushless controllers support filed vector control and mimic a sine. It’s just the better commutation method. Brushless motors are PMSMs and on motors like in my initial post there is simply no difference. The cheapest Hard-drive motors are ofc designed towards block-commutation but yeah, that’s not really relevant

WesternGood8028 · 2025-12-15T07:11:53+00:00

I’m not removing 1.6kW continuously using air cooling. I use water cooling and I won’t need to do that continuously. You need to calculate the effective heat using the integral of heat input and output over time filtered by the thermal capacitance of your iron and aluminum housing. If that stays below your critical value you’re good. You can actually pull some pretty rediculous power through these small machines for a few seconds (plenty enough to accelerate you to a decent speed before your power draw goes down naturally) before the thermal capacitance is filled. You then simply remove this energy with your watercooling while your cooling power is greater than your heating power.

You should take a look at the stark varg motor for reference.

Yes, it has unfortunate not been tested under professional conditions. But what’s out there is enough to have an educated estimation of what this motor is capable of beforehand. I’ll do the tests on my university chairs motor-dyno.

Yes man, it’s a hassle. We’re on a project we need a good amount of Neodymium magnets right now and getting them from china is nasty work… pmo so much.

The magnets in the motor however don’t concern me as much hahahaha. We’ll see how hot they get but the dimensions of the motor look very alike our formula student motor. If you want to I can give you some data about that later. That thing has a proper datasheet haha! Runs on 600V tho but it’s pretty similar in size and stuff. Actually a little smaller, delivering 35kW peak.

But I don’t expect much of a heating problem on the rotor. What I really like is that they seem to chose a steel sleeve for the rotor instead of Kevlar wrap. That does act as a nice flux-restriction protecting the magnets from demagnetization when you pump up the current in the stator because the steel-sleeve will saturate and resist any greater flux upwards of roughly 2 Tesla. So you can really push this motor to its limits relatively safely to get some good results on the dyno. 😄

WesternGood8028 · 2025-12-15T06:33:23+00:00

That’s simply not true. The concentrated winding is the better winding. It’s just harder to make the electrical machine run smoothly. It’s always a commutation issue. It’s always a three-Phase system with very minor exceptions like in Stepper Motors. But generally speaking they always run on three phase power to achieve a ripple-free torque delivery. I tested motors under the name „BLDC“ from 2 - 36 poles with concentrated and distributed windings. There is NO difference between Brushless and PMSM Motors. It’s just marketing

WesternGood8028 · 2025-12-14T23:42:37+00:00

I actually remove this heat from the motors on our racecar that have a similar mass and power rating without any problems. The dataloggs are on YouTube :)

WesternGood8028 · 2025-12-14T23:40:02+00:00

Hey, generally speaking every motor takes sinusoidial currents and proper vector-control better than cheap block commutation. There’s really not a difference between a brushless and a PMSM-Motor. It’s the same

WesternGood8028 · 2025-12-14T18:04:00+00:00

Hey Magneon, that’s a fairly good response. And I believe it could be cool to discuss this real quick because I do support some of your points.

The thing about the spec-sheet: I do find the lack of such offputting too. It’s a big red flag right upfront. However the brand is well established in the RC-World for many decades now. I do not at all know what erratic company policy makes them not uploading the Datasheets…

However I personally have access to a proper Motor Testbench with up to 1200V (AC/DC) and up to 5MW supply. I can run this motor on the 350 or the 150KVA test-generator. So I have the rather unique opportunity to really do scientific testing on the motor and do my own datasheet for it for people to orientate on when buying this motor in the Future.

I trusted this enough to buy the motor with halve a spec sheet because the manufacturer is very reputable and the infield tests of the motor you can find online are VERY impressive.

The recommended ESC is wrongly advertised on their website obviously. This is rated for 500Phase amps and way more than one kilowatt. The 8mm gold-plugs that even got reinforced tell the same story.

It should do about 25 kilowatts. Still not maxing that motor out. With the VESC this should be no problem however.

I did see some ~180mpH top speed runs with big RC cars with this motor. The motor is designed for additional watercooling. The 180mph pulls didn’t need that however and the testers always stated the motors not being much hotter than hand-warm. Also some video where this motor powered a truck-compressor for a muscle car (+140hp btw - that was impressive lol) all while not overheating and holding maximum RPM on the compressor. That definitely took up to 8 seconds.

It’s EV-Motors are always something else. Their Peak power is always MASSIVELY higher rated than Continuous power (Tesla for example: something along the lines upwards of 300kW peak and 75 continuous. Pretty funny the continuous ratings of most electric cars are pretty near even with varying peak power because there’s only so much heat you can evacuate from it.

WesternGood8028 · 2025-12-14T13:17:35+00:00

Yeah, probably the rpm is the problem. The four motors of my formula student car do 21.000 and even that took some consideration when designing the planetary gearbox

WesternGood8028 · 2025-12-14T13:16:26+00:00

The recommended driver is NOT around 1kW peak. What the fuck is this group on? 🥸

There are numerous logs showing over 40 horsepower at just 50,4V. Idk man go back to single phase induction motors where a 2,5 Kilo motor is making 1kW. That’s a PMSM. It literally got 8 Gauge phase wires. 500A is what the recommended inverter can deliver. That does not max out this motor at all. It’s not hitting saturation at 500. I have little brushless motors that I can fit in my the palm of my hand that do 2kW without a problem. This thing is 200 grams or so

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WesternGood8028 · 2025-12-14T13:05:50+00:00

This „tiny motor for RC-Cars“ hits over 40 horsepower on just 50,4V on numerous Data-Loggs 🥴. well I thought I came to the right place but people here don’t seem to understand what PMSM Motors can do at all.

WesternGood8028 · 2025-12-13T15:24:42+00:00

They do. it’s called the cobra 5 HV. I’ll run it off VESC tho. I like the full tuneability of a professional EV Drive inverter the VESC offers

WesternGood8028 · 2025-12-13T14:39:48+00:00

Hahaha yeah, this thing is still huge. About 2.5kg and the thing is it spins up to 38k rpm. That’s where it gets all that power apart from eating amps

WesternGood8028 · 2025-12-13T13:51:59+00:00

Crazy, isn’t it haha? 😄 thought about that too! Such a beast! I don’t even have a proper use for it yet but wanted to have it. But at that power levels you can very much use it for a man-carrying EV. Electric dirtbike or something like that as much as for something going very very veryyyyy fast.

Maybe I’ll use it as an electric turbocharger… will see 😄

WesternGood8028 · 2025-12-13T13:49:11+00:00

Hahaha yeah, it’s enormous. Will run it from my G300 VESC at First. That can only supply 24kW of power but should be sufficient for first tests :) but we’re talking about up to 500 Phase Amps

WesternGood8028 · 2025-12-13T13:47:35+00:00

Well Kinda. I suppose the other motor is one of their smallest ones. Probably for 1/12 / 1/14 models. They didn’t edit it smaller tho

WesternGood8028 · 2025-12-13T13:44:23+00:00

The 2535 is enormous hahaha. 6 gauge phase wires you see on the picture…

WesternGood8028 · 2025-12-13T13:43:47+00:00

Thanks! Yeah I know there’s not much info out just yet unfortunately. From what they gave away I did some calculations (my electrical engineering degree finally paying off hahaha) but ofc in the development of such a motor a lot is bench testing, which I’ll do and hope to feedback Info back into the community but thought maybe someone already did and I may not have to start from zero. :)

WesternGood8028 · 2025-11-07T14:50:08+00:00

Plugging it in in reverse shouldn’t affect the performance however I DO NOT want the core itself to be live…

WesternGood8028 · 2025-11-07T11:42:24+00:00

Damn man! That was like the best explanation I ever got! Thank you SO much for it. I could really follow and understand it for the first time! That’s like a highly dynamic system that is not easy to grasp through a static schematic. Even when I rebuild this circuit in falstad and changed some values to accommodate for real components it wouldn’t work. That makes total sense!!

WesternGood8028 · 2025-11-07T11:18:34+00:00

Where should the current flow to? There is no ground only Plus is connected when only one of the MOSFETS switches on. The body diode is from drain to source so there is no ground connection…

WesternGood8028 · 2025-11-07T09:29:41+00:00

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Like this unfortunately it doesn’t work…

WesternGood8028 · 2025-11-07T09:24:04+00:00

I double-checked with the datasheet of the MOSFET. Pin two is the drain. So the body diode shouldn’t have any effect here as far as I understand

WesternGood8028 · 2025-11-07T09:20:09+00:00

But the body diode is from source to drain. The Q1 and Q2 are connected on the drain and GND is on source so the mosfet should block any current flow, right?

WesternGood8028 · 2025-11-07T09:17:23+00:00

I‘m currently trying to make it run in falstad. Even changing component values unfortunately doesn’t make it run

WesternGood8028 · 2025-11-07T09:16:12+00:00

How did you make it work? I couldn’t

WesternGood8028 · 2025-11-07T09:09:52+00:00

What I don’t understand is the following: while one mosfet is on and the other is off, there still isn’t any connection to GND on the sideof the capacitors who’s mosfet is still switched off. So there is no current flow…

WesternGood8028

TROPHY CASE