Lab equipment for working with Motor controllers and drivers

[SirRage]

Hey there!

I really want to learn about motor controllers and in particular motor drivers. I'm new to hardware development but having fun learning it. This series was helpful as a primer, https://www.youtube.com/watch?v=gNpoTPzEkco, so now looking at trying to build some the circuits discussed in the video and dig up more material about the components.

The components that I want to build and test would be: 3 phase inverter, buck converts connected and tie it together with a TI C2000 microcontroller. One of the reasons for tying the motor controllers closer together would be to sample both the rotor encoder and linear encoder to map deltas between them.

I have SDG 1025 Arbitrary waveform generator and a Rigol DS 1054. I was thinking about getting a spectrum analyzer, just not sure how it would be helpful yet outside of electrical emissions testing. I was thinking about getting a better scope but not sure if a gigahert scope would really benefit me yet.

The two bits of kit I was thinking about getting were: siglent SSA3021X Plus and a SDS2102X Plus

Thanks for the input!

[rstofer]

Microchip has a lot of app notes on 3 phase drivers and such.

Google for 'microchip 3 phase inverter' or something similar.

[Ian.M]

If you will be working with voltages over 50V, much of your investment will need to be in enough differential voltage probes and isolated current probes, with sufficient bandwidth to monitor key parameters of all the phases of your drive's output stage.   If its a direct from mains drive, the probes had better be at least Cat II rated, with an adequate working voltage margin above your worst-case DC bus voltage.

Otherwise, *when* (not if!) your new drive design decides to convert itself to silicon shrapnel, its got a high probability of taking out your scope, and possibly its operator as well, leaving no signal data for a failure analysis, (and if you were dumb and won a Darwin award by floating your scope, no-one to do the failure analysis)!

[SirRage]

Thanks for the advice!

I'm probably going to be okay with 25mhz probes. I don't think it would be any faster than that for my application. It is a bit expensive but 300 USD a prob is better than blowing something up.

I'll see if I can build a low voltage version first. Just have to find a small AC servo motor I suppose.

[mazurov]

You may want to also build a device similar to one in the picture. It's a "dummy load" for BLDC motor controllers.  Left motor goes to the controller, right has its windings shorted together. Works very well :-).