Recent content by fictivedesigns

Hi Georg, in your second photo the high side FET has finished turning off by ~160ns after cursor A. It looks like you are measuring from Gate_high to GND and Gate_low to GND. Remember that Gate_high to GND = Vgs_high + Vds_low. So in this case you are not directly measuring Vgs but the sum of...

Axial, the docs are here: https://blog.x.company/sharing-makani-with-the-world-the-energy-kite-collection-ea49398df78c Unfortunately it doesn't look like they released every single internal document. I wasn't able to find any controller source files, but if you just want to use the firmware...

Nice progress! Interested to see what you plan on doing with these motors. ~32kg mass, ~200kW peak could make a lot of fun stuff 8) . Only problem is you need insanely high bus voltage to get max power out of these things. Since power is proportional to voltage (at a fixed motor current) a 72S...

Check out the design doc by Andrew Goessling for this inverter here starting page 147: https://storage.googleapis.com/x-prod.appspot.com/files/Makani_TheEnergyKiteReport_Part2.pdf A few things: The SiC modules are 1700V rated and the 1100V caps are put in series to handle the voltage. The...

Wow, nice teardown and nice score. This is insanely interesting! Here are some of my thoughts: I saw that each film cap is rated to 1100V, so unless they are connecting caps in series that limits their max working voltage to 8-900V (due to thermal derating; it's 80% VRated at 80C). 1100V also...

Are you referencing this paper? http://www.hitachi.com/rev/pdf/2004/r2004_04_102_3.pdf The alternator here is pretty much standard, maybe with a small amount of permanent magnet assist. There is a rotor field winding powered by slip rings. You need to power this and it works pretty much the...

This is a separately excited DC motor- your rotor connections are A/B and your field connections are C/D. There are controllers out there that can take advantage of SepEx motors, or you could just connect C/D to a battery and use A/B like a traditional brushed DC motor. E/F could be a bunch of...

The SPI interface along with the motor sensor offset parameter indicates that the sensor is being used in the absolute angle mode, which makes sense- you really want as much angle information as possible for high-performance motor control. There's a reason you only see absolute encoders and...

Chances are your inverter and encoder use the absolute angle interface. It's SPI. The upper left-hand connector labeled ENC has 2 labels, RACS and RACLK which are typical SPI signals. I think VESC has some kind of support for ams encoders but if it doesn't it's possible to write some code to...

Your PM300CG1C065 IGBT brick has 6 integrated gate drivers for each of the 6 switching IGBTs in its 3-phase bridge. Those Avago parts are optoisolators used to send signals to those integrated gate drivers and provide galvanic isolation from LV to HV. The 4 transformers along the bottom of the...

As an update: I bought the L5055-400, and it turns out to have an inductance of 47uH phase to phase. Perfect! David

Intuition tells me that is the case, but from the two samples I have the actual motor design appears to matter far more. In fact the NTM 5060 has both a lower KV and a higher core mass, yet its inductance is less than half of the smaller, higher KV SK3 4250. David

Hi all, tl;dr: Are there any good sources for short can (<55mm from mounting plate to end of bell), moderate to high inductance (> 40uH phase to phase) BLDCs? Ideally the motor shaft is >= 6mm and the motor diameter is <= 50mm. First, some background. I'm an undergrad developing a dual motor...