are there motor resolver models out there?

Has anyone modeled a dc motor and resolver in multibody or other? Looking for an example rather brute force attempting including learning curve.

[Sahas]

Hi @Robert,

Modeling a DC motor with a resolver in Simscape involves creating both mechanical and electrical components and integrating them with control logic.

The following MathWorks documentation links on "DC Motor" model, "Rotational Motion Sensor" block and "Transform Sensor" block might help you with the requirement.

• https://www.mathworks.com/help/sps/ug/example-modeling-a-dc-motor.html
• https://www.mathworks.com/help/simscape/ref/idealrotationalmotionsensor.html
• https://www.mathworks.com/help/sm/ug/rotational-measurements.html#buams4l

I hope this is beneficial!

[Umar]

Hi @Robert,

This example in the following link should help answer your question. https://www.mathworks.com/matlabcentral/answers/472087-how-to-model-a-dc-motor-hoist-with-simscape-multibody

Please let me know if this helps resolve your issue.

[Umar]

Hi @Robert,

Based on the documentation shared by @Joel Van Sickel, you can start by creating the electrical and mechanical models of the DC motor. Define parameters like armature resistance, inductance, back EMF constant, and torque constant. Instead of attempting to model the resolver in a multi-body environment, you can utilize the dedicated Resolver block in Simscape which effectively models the electrical phase angle of the rotor using electromagnetic coupling, which is necessary for accurate feedback control. Then, integrate the DC motor model with the resolver block by making sure that the connection between the rotor position sensor and the motor control logic is correctly established for real-time feedback.

Example Application

A practical example is the “Three-Phase PMSM Traction Drive”, which controls rotor speed using a high-fidelity resolver. This model showcases how to effectively integrate a resolver with a DC motor, demonstrating the use of speed and position control loops by clicking the link below.

https://www.mathworks.com/help/sps/ug/three-phase-pmsm-traction-drive.html

When modeling the resolver, consider the coupling coefficients and transformer characteristics. The block allows for two options:

Omitting Dynamics: Neglect the inductive terms, suitable for sinusoidal inputs.

Including Dynamics: Capture voltage amplitude loss and phase differences, valid for any waveform.

Please let us know if you still need assistance or have any further questions.

Answer 1

[Joel Van Sickel]

Modelling the resolver in multi-body won't be effective because multi-body doesn't have a magnetic domain, so there is no benefit in modelling the actual mechanical motion of the resolver through 3 dimensional space. Instead, you should use the resolver block based on the motor rotor position with this block: https://www.mathworks.com/help/sps/ref/resolver.html and associated exapmles (it works just as well on a dc motor model in simscape electrical as the 3phase machines)