Alternative motor windings and drive schemes

[Clugh]

⚡ What Electrocaloric Cooling Is


Electrocaloric cooling uses special dielectric materials that heat up when an electric field is applied and cool down when the field is removed. This reversible temperature change is called the electrocaloric effect (ECE).

According to research, the effect comes from how electric dipoles inside the material align and disorder under electric fields

Electrocaloric (EC) cooling is a solid‑state refrigeration method based on the reversible temperature change that occurs in certain dielectric materials when an electric field is applied or removed. It’s especially relevant today because multilayer capacitors (MLCs) made from relaxor ferroelectrics like PST (PbSc₀.₅Ta₀.₅O₃) can generate large EC effects at practical voltages.
1. Basic Mechanism


EC materials contain electric dipoles that can switch between ordered and disordered states.

• Apply electric field → dipoles align → entropy decreases → material heats up
• Remove electric field → dipoles randomize → entropy increases → material cools

The cooling step is the useful part: the material ends up colder than it was before the cycle. 2. The Electrocaloric Cooling Cycle


A practical EC cooler runs a four‑step cycle:

1. Apply E‑field Material heats up due to dipole alignment.
2. Reject heat to a sink Heat is transferred out via a thermal switch or conduction path.
3. Remove E‑field Dipoles disorder and the material cools below ambient.
4. Absorb heat from the load The cold EC element pulls heat from whatever you’re trying to cool.

Repeat the cycle at high frequency and you get net heat pumping.
3. Why It Matters for Power Electronics

• 100% solid‑state (no compressors, no refrigerants)
• Potentially high efficiency near phase‑transition temperatures
• Scales well with multilayer capacitor manufacturing
• Suitable for chip‑level thermal management
• Demonstrated temperature lifts >10 K in some device architectures

Relaxor ferroelectrics like PST, PMN‑PT, and related materials are currently among the strongest EC performers, especially when built into MLC structures that allow high fields at low voltages.

[Clugh]

Something I find interesting and somewhat new in power electronics are PST MLC's

What Are PST Multilayer Capacitors?


A PST multilayer capacitor (MLC) consists of:

• Many thin alternating layers of PST ceramic and internal electrodes
• A stacked structure that allows high electric fields at low voltages
• A macroscopic working body suitable for electrocaloric cooling

These devices are often manufactured by companies like Murata, which collaborates with academic groups on PST‑MLC research.

PST multilayer capacitors are being explored for:

• Electrocaloric cooling modules
• On‑chip thermal management
• Energy‑efficient refrigeration
• Solid‑state heat pumps

Their compact size and compatibility with existing capacitor manufacturing make them especially attractive.

[Clugh]

Spulen-Halbacharray



More information about a dc coil based Halbach array. Its nothing new. They don't use it because the dc excited coils suffer high losses.

Creating a Halbach array requires rotating magnetization vectors around the circumference. With permanent magnets, this is easy—just orient the blocks.

With coils, you must:

• Shape the coil geometry to produce the correct vector field.
• Drive each coil with the correct DC current magnitude and polarity.
• Manage heat, since copper coils dissipate power continuously.

This becomes:

• Bulky
• Inefficient
• Expensive
• Control‑intensive

Unless you use superconductors (HTS), the losses are too high.

Yes, coil‑based Halbach arrays exist, but only in research or specialized applications. The only practical implementations use HTS coils or patented electromagnet arrays, not conventional copper DC windings.

A pm based Halbach is much simpler and compact. It does not suffer from additional excitation losses. The hybrid wound BLDC are even simpler than that.

There are also other applications for a coil based Halbach array.


INTRO:

"Since 20th century, superconducting magnets have become one of the most beneficial superconducting applications, which are widely utilized in Magnetic Resonance Imaging (MRI) and other biological equipments [1]. Superconducting magnets are able to generate magnetic fields with desirable h o m o geneity and strength up to tens of Tesla ."

You may read for yourselves.....

Optimization Study on the Magnetic Field of Superconducting Halbach Array Magnet

Boyang Shen*, Jianzhao Geng, Chao Li, Xiuchang Zhang, Lin Fu, Heng Zhang, Jun Ma, and T. A. Coombs** Electrical Engineering Division, Department of Engineering, University of Cambridge, CB3 0FA, UK

[Clugh]

If you enjoy tinkering and want to build a high-torque machine without magnets and with less control complexity, consider a 12/8 DC-excited flux switch machine. The topology is simple, featuring 6 DC field coils and 6 armature coils with a laminated rotor. This would be a very eazy machine to have the laser house cut. It also has a much higher rpm tolerance mechanically. On this one the engineers dove tailed the rotors teeth. IEEE approved as a viable form of e traction that would be more affordable without the rare earth.

[Clugh]

The other thing is the build complexity. Halbach arrays are part of the rotor so a dc field excited rotor would require some type of slip ring configuration. The dc field coils would have to be able to rotate...:grimacing: and then you still have to wind the armature and control it also....

[Clugh]

Spulen-Halbacharray



More information about a dc coil based Halbach array. Its nothing new. They don't use it because the dc excited coils suffer high losses.

Creating a Halbach array requires rotating magnetization vectors around the circumference. With permanent magnets, this is easy—just orient the blocks.

With coils, you must:

• Shape the coil geometry to produce the correct vector field.
• Drive each coil with the correct DC current magnitude and polarity.
• Manage heat, since copper coils dissipate power continuously.

This becomes:

• Bulky
• Inefficient
• Expensive
• Control‑intensive

Unless you use superconductors (HTS), the losses are too high.

Yes, coil‑based Halbach arrays exist, but only in research or specialized applications. The only practical implementations use HTS coils or patented electromagnet arrays, not conventional copper DC windings.

A pm based Halbach is much simpler and compact. It does not suffer from additional excitation losses. The hybrid wound BLDC are even simpler than that.

[Clugh]

Gotha is in the house...

So look at this reality....👀

A yge 320 Rm is .0007 a scorpion Tribunis 14-300 is .00065 block commutation and so itz no doubt stronger and faster than the old antique YGE 320.
Do you all see a castle lite 200 is almost as strong as the 320 and much lighter. It is more power dense than the 320...:cry:

I know it can log 380 amperes empirically because I did it driving a Phil Thomas SS45 fully underwater like a submarine. But if you compare the YGE to even the 20S version APD it isn't even close. It literally has half the internal resistance than a 320. Twice as powerful.

Honesty will set the 8 pilots free. And the 16S version of the APD really kills a YGE 320.

This makes me seriously wonder do hobbyist just listen to people online they think knows something or do they know where to look for it and actually spec the devices for themselves . :grimacing:

The castle's still runs today . It has never been in for a repair almost 10 years now its run without a flaw in models and on the test bench. No matter who gets mad about it the YGE's are nearly at the bottom of the pile for power density. Part load operation is also inferior to the APD which has synchronous rectification.

So a much better active freewheel operation and brake with much more PWM capability on top of double the power density.

If you have a problem with this you can work it out with a fellow German, George Ohm.

Please enjoy the relevant and real specifications of your chosen device.

Hope you are "Sequre" and that no one else falls for it :bomb:

Talk to you later.
Hubert

[Clugh]

Facts about some inverters discussed over the last few years


APD 120 F3 Rm .0011
APD 200 F3 Rm .00055
APD HV pro 300 20S Rm. .00033
APD HV pro 300 24S Rm .00091

Here are some internal resistances for YGE in comparison They can be found in the German ecalc databases hiding from the Americans.

YGE 120 Rm .0018
YGE160 HV Rm .0013


Castle's
Pheonix edge HV lite 160 Rm .0011
Castle edge lite 200 Rm .0008
Castle edge lite 130 Rm .0010

Don't care what brands people like this is reality. At WOT the YGE runs hotter with more resistance than everything else....:stuck_out_tongue:

[Clugh]

Hi ,
This is something you and your friends at motors by Gotha should keep in mind as it pertains to forums technical discussions and false narratives about proven winding technologies, machine failures, and solutions as well.

Honesty is absolutely critical in any technical debate for several reasons:
1. Accuracy of Information

Technical discussions rely on facts, data, and logical reasoning. If participants are dishonest—by misrepresenting data, exaggerating claims, or hiding limitations—the entire debate becomes flawed. Decisions based on false information can lead to system failures, wasted resources, or safety hazards.
2. Trust and Collaboration

Engineering and technical work often involve teams. Honesty builds trust among team members, enabling open communication and constructive problem-solving. Without trust, collaboration breaks down, and people may withhold ideas or feedback.
3. Problem-Solving Integrity

Technical debates aim to find the best solution, not to “win” an argument. If someone is dishonest to protect their ego or push an agenda, the focus shifts from solving the problem to defending positions—leading to poor outcomes.
4. Ethical and Professional Standards

Most technical fields have codes of ethics (e.g., IEEE, ASME) that emphasize honesty because technical decisions can impact public safety, financial stability, and environmental health. Dishonesty can cause catastrophic consequences.
5. Long-Term Reputation

In technical environments, credibility is everything. If someone is caught being dishonest, it damages their reputation and can affect career growth. Conversely, honesty—even when admitting mistakes—builds respect.

Sorry there is not more to report here... enjoy your subscriptions:face_with_monocle:


Remember this......

The IEEE and other such entities strive to maintain that code of ethics. The data driven information provided from such groups is not motivated by a sale or maintaining someone's ego. Intelligent individuals can clearly understand this reasoning.

Happy Hybrids....
Hubert

[Clugh]

Adam has a direct drive contra Halbach with PARALLEL slots for F3A but it didn't win the worlds. :stuck_out_tongue: A single pyro 600 with a traditional wind with a contra planetary gearbox did so already you'd be going backwards. The Halbach is PM heavy machine. Very few in the EV world are currently looking at a Halbach for ma$$ production. It's quite the opposite; they are looking for pm-less solutions. Like synchronous SRM's. Considering that the better solution for the average hobbyist that actually winds his own motor is to wind an adequate wye to delta serially connected machine for tangible improvement over the 12N10P wye windings that have already won many championships in various E flight classes.

[Clugh]

:point_up:

Its old news that if the ratio of radial component to the main poles isn't correct in the Halbach the torque ripple increases versus being minimized a 12N10P/14P hybrid wind is so much simpler...

[Clugh]

By the way there is nothing new about a 3d printed machine using zip drive iron or the 14 pole halbach that never ran. It is funny about the 50/50 radial to circumferential ratio as that determines how sinus the BEMF would be. The wrong ratio and it is no cleaner than a BLDC. The ratio is critical to a sinus signature. This was pointed out and the response was ad hominem, & fallacy, and then you never see it run.

It would be better to utilize additive manufacturing and print something actually useful in a real motor like semi magnetic slot wedges or a low loss magnetic core with a real rotor that will not fall apart.

You waste alot of time when custom winding solutions are available and easy to implement for experienced winders. They actually run too.

No dreaming or nonsense just reality!


The technology of 3d printed motors and components is nearly 15 years old now. Its definitely nothing new, exotic , or special about it. 7 years and you still have not managed to simply wind and run a hybrid on a conventional BLDC frame for examination.

Offenbar ist es sehr schwierig, eine sinnvolle Unterhaltung über Motorsteuerung und -design zu führen, die tatsächlich zu einer Verbesserung für den Hobbybastler führt.

:woozy_face:

[Clugh]

ABC 1818 calculated as most efficient prop in its database for performance hydro @ 12s lipo 9800 mah

33,940 rpm
153 amps
Pin 6.394 kilowatts
Pout 6.125 kilowatts
Run time 3.85 minutes
Est speed 90.12 mph or 145.03408 km/h
Eff. 95.80 %

In a performance hydro with 10s lipo @ 9800 mah and a castle 240. Prop wizard selected an ABC 1918 as the most efficient prop for the setup.
Resultant:
28,221 rpm
141 amps
4,955.78 watts Pin
4,728.58 watts Pout
run time 4.15 minutes
est speed 79.20 mph or 127.46 Km/h
Eff. 95.42%

[Clugh]

Here is the H1818 raw beryllium blank I'll ask Brian to prep for my 1/8 scales. This prop and the 1919 is prop wizard selected specifically for my custom wound Align.


And some other goodies for the spring....

[Clugh]

If you think your motor has torque turn a few of these boat props. These supercavitating surface piercing boat propellers have aspect ratios of 2.3 and 2.4.. I bet you get the smoke without the 8 blades...

[Clugh]

Guten Morgen Ralph! Immer noch Abonnent... Ja, ja, gern geschehen... Ein paar Kreise nach dem Flug zu drehen, wird die Magnete in deinen Geräten nicht retten, deren Curie-Temperatur offensichtlich überschritten wurde. Also hör bitte auf, im Forum Dinge zu behaupten, die nicht im Entferntesten der Wahrheit entsprechen.

Der Hauptgrund für übermäßige Hitzeentwicklung ist eine Belastung, die der Motor nicht dauerhaft bewältigen kann. Es handelt sich um einen Motor, dessen Leistung für die erforderliche Last nicht ausreicht. Dies ist auch der offensichtlichste Grund für eine Desynchronisation. Das erforderliche Kippmoment ist schlichtweg nicht vorhanden.

Viel Spaß mit Ihrem "neuen" Konto!



Thank you.
Hubert

[Clugh]

BTW I finally linked with Brian Buass to prepare my ABC propellers for SAW and oval speed runs. We are both looking forward to working together.

Im sure alot of you...didn't know or do not know that Brian wound the motors and built the airframes they flew that competed in the 1998 F5D World Championship. Brian currently hold several records in fast Electric boats. He also has some pull at castle...

Generally he is just and all around highly accomplished Modeler. Nothing he builds is trash and always fast as ever.


In the attachment is some of his. ABC prop work

[Clugh]

Question:
If you buy an economy based inverter the have to hack it with an Arduino microprocessor or whatever to be full featured. In time and extra componentry what have you saved? If you need to reinvent its heatsink and print a case for it to house real bulk capacitance etc. What have you $$aved? It's cool to tinker like that if that is what excites an advanced hobbyist. But if you are really into higher challenges why hack versus build a purpose built embedded flight solution withe real capability for UAV flight. This also supports Estonia instead.

YOU... wont build anything with a shorter current path. It is also floating point space vector control.

[Clugh]

I have 3 FR power 4730 560 Kv motors coming in from Fabrizio , the owner, to tune. I'm doing one for him and the other 2 I get to keep. I will put them up for sale. Here are the OEM specifications.

The motor is normally 468.00 USD!!



Stator Diameter 47 mm (1.85 in)
Stator Thickness 30 mm (1.18 in)
No. of Stator Arms 12
Magnet Poles 10
Motor Wind 5+4Turn Delta
Motor Wire 2 Strand 1.0 mm
Motor Kv 560 KV RPM / Volt
No-Load Current (Io/10V) 2.29 Amps
Motor Resistance (Rm) 0.011 Ohms
Max Continuous Current 150 Amps
Max Continuous Power 7500Watts
Weight 550 Grams
Outside Diameter 58.5 mm
Shaft Diameter 6 mm
Body Length 58.7 mm
Overall Shaft Length 110 mm
Max Lipo Cell 12s
Max Peak Current 270 A (2 seconds)
Max Peak Power 13500 Watts (2 seconds)
Motor Timing 5deg-8deg suggested auto timing

FR Power like CK Aero Flies with Clugh

Bi Bi... 😛
Hubert

I definitely plan to strip it of its large conductor bifilar nonsense. Especially a delta with additional large parallel conductors that are already subject to skin losses in major proximity to one another with no twist. The lower DC resistance is not worth the AC noise as the AC resistance can be as much as 10X's higher.. All that noise heats the magnets and iron up quicker....the perfect precursor to desynchronization.

Your speed plane becomes a smoke crop duster.... gliding it around a few minutes after a speed run is not going to save the magnets. That! is obviously proven in the tragic videos on you tube where they are left with no choice but to glide because the motor is already gone:scream:

Once the magnets in the rotor reach a certain temperature they cannot return to full power by cooling them down. I don't care how quickly you try to cool them back down.

This after run gliding was suggested as a remedy to cool motors that are blowing out magnets at temperatures greater than 180 degrees Celsius and it is real BS! The proof is right there on the bench of the editor in Gotha, trying to put it on the pilots that cannot be at fault if they are told the motors can make clean power that they cannot..:face_with_monocle:

DC does not generate losses based on frequency. DC is stall in a BLDC motor boo boo. The eta there is 0% You need to learn to accept that as life.

:flushed:

And isn't it quite silly to run a motor in a speed trap competition with an antiquated or economy based inverter without an iota of motor telemetry in the first place???

You might know the real in flight motor temps then and pierce right through any goofy lies posted on social media. :partying_face:

Economy pricing and high end competition for speed records do not go together anyway. :woozy_face:

[Clugh]

Hydra Cobra 5 is 12s lipo with big amps. (12S XLX Hydra with new features)

HYDRA COBRA 5 NEW FEATURES:

• 32-Bit processing power for smoother motor control and improved response time.
• Enhanced Data Logging includes:
  • Double the maximum sample frequency of older generations.
  • 8x increased logging time of older generations.
  • ESC electrical motor timing data.
  • Acceleration data via onboard accelerometer.
  • Looping feature prevents interruptions in data log recording.
• Additional tuning features include:
  • Improved braking adjustability
  • Separate brake and reverse curves
  • Highly adjustable internal BEC (5.0V - 8.5V adjustable in 0.1V increments)
• Access to tuning options and firmware updates for free with Castle Link V4 USB programmer included with purchase.
• Optional smartphone-based programming with the B-LINK™ 2 Bluetooth Interface(sold separately) and free Castle Link 2 app available on Google Play or Apple App Store.
• Upgraded current-sensing and thermal protection system actively mitigates the risk of failure in aggressive or high-load setups. Ready

Happy 2026!

This is a quality investment.