Motor Testing - MSXV

Owned by Soumav Maiti
Last updated: Mar 11, 2023
5 min read

Docs/Downloads

Profinity Software (must download)

https://docs.prohelion.com/Profinity/Overview.html
- Used to control motor configs, should automatically recognize your motors/port if set up correctly

Wavesculptor (Motor Controller) Documentation

Motor Documentation:

Motor Documentation

Electrical Setup

Parts required:

  • Mitsuba motor

  • Tritium WaveSculptor 22

  • 2 power supplies (HV & LV)

  • CAN-Eth bridge adapter

  • (optional) eth-usb (or usbc) adapter

  • *relay/contactor

  • *MCI board

* MCI board and relay not required when low voltage testing

Wavesculptor setup

The motor runs off the HV power supply, and is powered through the Wavesculptor 22. Though the motor runs off AC, you directly supply the Wavesculptor with DC voltage.

To power the Wavesculptor, connect the HV power supply to the DC NEG and DC POS terminals on the left.

The CAN-bus terminal on the wavesculptor also needs to be powered by a low voltage (12V) power supply

The motor runs off of a 3-phase AC voltage. To power the motor, connect the OC, OB, and OA wires directly to the motor.

On the wavesculptor, you can see a section called ‘motor’ with a lot of wires. Connect the ‘motor’ wires directly to the motor. These are the signal wires used to control the motor.

Finally, connect the ‘CAN bus’ wires to the CAN-eth bridge. If you don’t have an eth port on your laptop, use an eth-USB (or usbc) convertor.

CAN-eth bridge setup

The CAN-eth bridge needs to be powered separately from the Wavesculptor. It communicates with your laptop so that you can control the motor controller with your laptop.

The CAN-eth bridge can be seen below and requires 12V of power. In the image above, the red wire is 12V, the black wire is Ground, the green wire is CAN-low, and the white wire is CAN-high. Make sure to twist the CAN wires together as they are a differential pair.

Software setup

After downloading the Profinity software, you are able to characterize and test the motors.

While powering the Motor controller and CAN-eth bridge, if your computer doesn’t automatically detect the two devices, you will need to manually add them in Profinity. This can be done by clicking on the ‘Add Device’ button and manually adding the two.

Note: add the tritium CAN-eth bridge, not the Prohelion one.

When connected and properly powered, it should look something like this.

 

It might take a bit of disconnecting and reconnecting cables to your laptop to make this work, as it’s a little finicky.

Characterizing the Motors

Motor Configuration

Now we can start to configure the motor. While this guide does go in-depth, I would strongly recommend reading the WaveSculptor Config Software User's Manual (especially Sections 4, 5, and 6).

If you right click on the WaveSculptor22 section on profiles, you should see something like this

Navigate to Setup and Configuration > tools > configuration to get to this screen

Depending on the type of testing you want to do, you will need to change the Sine, SixStep, and IDC current limits. These limits represent the AC rms sinewave current going out of the Wavesculptor, the DC stepped voltage current going out of the Wavesculptor, and the input DC current into the Wavesculptor, respectively.

Before any testing gets done, go to the configuration ‘motor’ tab on the configuration page and set the relevant settings based on the motor datasheet (pole pairs, motor type)

Line Resistance & Inductance configuration

To find the line resistance & inductance (in the coils) we need to do the ‘param extract’ test. This can be found under wsconfig > tools > paramextract.

To perform this test, the motor will apply a series of voltages to determine the resistance. Unfortunately, this will move the motor. When the motor moves, it generates a back emf which will cause the calculated resistance and inductance to differ. In order to avoid this, have someone hold the motor steady when the test runs.

When ready, press the ‘extract params’ button in the bottom left. The final result should look something like this

Ideally, the red and blue lines will match as similarly as possible. (It might help to get someone else to hold the motor in place, the less movement the better)

Phasor/Hall Angles

In this test, the motor determines at which angles to activate/excite the hall effect sensors, in order to maximize efficiency. To run this test, go to wsconfig > tools > phasorsense.

In order to do this test, have someone continually spin the motor, while the other member clicks ‘phase acquire’, if successful, the software will let you know. A correct reading will look something like this:

AFter this is done, you should be able to operate the motor!

Operating the Motors

WARNING: By using a power supply to test the motors, we do not want regen braking to occur because power flowing back into the power supply will damage it!

 

To prevent this, make sure ‘Motor Current’ is set to zero before changing the velocity.

When you want to spin the motors, set ‘Velocity’ to a certain speed, then ramp up ‘Motor Current’ and you should expect the motors to spin.

Note: if you set the motor current too low (i.e. < 1 A), the motors may not spin.