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    HyMag tech boosts magnetic flux density of permanent magnets by 10-30%

    There's also PM wire announced a few months ago as well, seems to be some sort of wire that can be pressed into shapes and selectively magnetized or something. https://www.designworldonline.com/pm-wire-magnet-manufacturing-technology-could-change-industries/ They didn't really explain a great...
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    Axiom: a 100kW+ motor controller

    What does the rotor look like though? If it's an IPM motor with reluctance torque, controlling it will be different to a conventional motor with surface mounted magnets.
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    Animation for High Torque ETM motor

    Adding loads of poles just increases torque density but it restricts the maximum RPM the motor can run at. Losses in the stator become too extreme if you try to run this type of motor at higher speeds. You can squeeze a little more with thin laminations and special materials but there's only...
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    Axiom: a 100kW+ motor controller

    What is the motor like? I assume it's an IPM like most other japanese EVs but I can't find pictures or details for this motor.
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    Axiom: a 100kW+ motor controller

    Nice, the VESC SVM scheme makes it look a little unusual. If you only sample v0 the FOC loop is effectively PWM/2, both v0 and v7 give you 1:1 with selected frequency. With this SVM scheme the low side only switches half as often, apparently it has slightly more torque ripple but 50% less...
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    Axiom: a 100kW+ motor controller

    Yeah, I looked at doing 100khz GaN VESCs a few times, at those frequencies you can eliminate the electrolytic caps and only have ceramic or ceramic + polymer caps. Those electrolytic caps contribute quite a bit to size and heat, you should also get some minor motor efficiency gains and possibly...
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    Axiom: a 100kW+ motor controller

    Did you decouple the ADC ISR from the PWM freq so PWM can be set to multiples of the ADC ISR?
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    DA-90 motor

    I couldn't find detailed motenergy efficiency graphs. I was looking at it compared to the 3kw golden motor axial flux motor. The DA-90 had almost 3x the peak torque at 0 RPM if you feed it enough current, at 4000 RPM the golden motor had lost over 50% of it's rated power and ceased producing...
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    Esc current sensing

    I have always put it before the shunt but it shouldn't matter, just don't do what I did and forget to put the relatively large 0.1uf filter caps on phase voltage sense output, I did that when building an inverter and it stops instaspin from working but it's easy to miss as they don't explain how...
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    DA-90 motor

    It looks like although peak power and efficiency aren't noteworthy it has quite a large RPM range where it has decent power and efficiency. It has a new winding method made by some russians using parallel star and delta winding. The heavy weight seems to be as it is an existing motor with new...
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    Duyunov wheel-hub motor

    Actually these might be quite good, looking at the dyno graphs the peak power and efficiency aren't notable, however they appear to have a broader operating range where they still outputting power with decent efficiency when compared to permanent magnet motors. It also looks like they can...
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    Esc current sensing

    Yeah, looks like it will be the best reasonably priced MCU for motor control, only thing it lacks is USB like on the 280069, I just wish they would hurry up with the software, it was supposed to be out when the MCU was released now it's been delayed 3 or 4 times.
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    Esc current sensing

    They still haven't released the instaspin software for the 280049. It was supposed to be out q2 or q3 2018 now it's q2 2019. :roll: The 280049 does look pretty good though.
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    Esc current sensing

    If you can stay under 80V the Ti ina240 is probably the best option. Anything above that and you will need complex isolated shunt sensors or magnetic based sense such as allegro ACS sensors.
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    Esc current sensing

    What voltage is the controller going be used for?
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    Axiom: a 100kW+ motor controller

    Yeah it has a variable that has to be set which I assume compensates for the lag, it drove me crazy for a while, since they don't explain how their observer works I initially missed the phase voltage filters on my boards not knowing they were critical and that instaspin can't function without...
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    Axiom: a 100kW+ motor controller

    Looks similar to how Ti instaspin foc motor detection works, you give it a target current and ERPM combined with a ramp up period to slowly build ERPM in open loop sinusoidal mode. The only difference is they have 0.1uf filter caps on voltage phase sense, they seem to be able to track the rotor...
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    Sensorless at standstill, development updates and status

    You can still sell IP and open source it, you just release it under a GPL license which requires the source code be distributed for the license to be valid, commercial customers typically won't want to release source codes for their products so you negotiate a non-GPL license with whatever terms...
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    Sensorless at standstill, development updates and status

    I reckon the best way would be to make it into an abstracted library coded in C using floats. You could run it on any 32bit MCU with a FPU and appropriate PWM/ADC hardware. Getting it up and running would just be a matter of connecting the code to timers and other peripherals for each MCU.
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    Sensorless at standstill, development updates and status

    I don't think there would be any issues with documenting it or making an open source version. I mean't when it comes to making some money off it, the business model of just selling it as locked down commercial software doesn't appear to work for other smaller companies trying to do similar. Open...
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    Sensorless at standstill, development updates and status

    There's not much individuals or small businesses can do if someone is desperate enough to steal code, all closed source does is punish legitimate users by making it difficult to use due closed obfuscated libraries or having to try and ship locked physical MCUs. Making it opensource also doesn't...
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    Sensorless at standstill, development updates and status

    What about crowd funding an initial open source release then charging for technical advice and feature requests? When it comes to open source FOC controllers there's very little around despite the demand, the only real option is the VESC which is quite good but Benjamin who made it is usually...
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    High side vs Low side PWM

    Usually high PWM freq and high switching speed allows you to have less bulk capacitance however it's more demanding on minimizing layout inductance and capacitor ESR. For 100khz you would typically expect to see SMD mosfets and ceramic capacitors placed 1 or 2 millimeters from the drain. Through...
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    DIY Super Capacitors, and Robert Murray-Smith

    I have been following him for a while as well. He says he is getting close to starting limited production and seems to have a work space set up. Interestingly I was talking to him in youtube comments, assuming he gets working ones he was unsure what sort of markets to sell them to. His current...
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    Switched Reluctance Motors

    The biggest difference between synchronous reluctance and switched is that sync ones typically have the phases all joined together like conventional 3 phase motors. Switched reluctance typically have completely separate phases that each have their own ground connection.
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