In the System Explorer window configuration tree, expand the Power Electronics Add-On custom device and select Circuit Model >> PMSM BLDC >> Mechanical Model to display this page. Use this page to configure the PMSM BLDC Mechanical model.
This page includes the following components, configurable at edit-time only:
Mechanical Model Section Channels
This section includes the following custom device channels. The value of an input channel can be modified dynamically at execution time.
Mechanical Model Description
Attached to the machine model's shaft is a basic mechanical model. This model was chosen due to its common application, and the ability to extend its functionality. The behavior of the model varies depending upon whether the Mechanical Model Mode is set to Torque Controlled (1) or Speed Controlled (0).
When the Mechanical Model Mode is set to Torque Controlled (1), the equation of the mechanical model can be expressed as follows:
There is a dead-zone implementation with the static friction torque; if the Electromagnetic Torque (Te) does not exceed the Static Friction (Tf) torque, the speed remains at zero.
Note that in equation , the value of the mechanical speed (ωm) is in radians per second, while the output of the Mechanical Speed channel is in RPM. The equation for the Electromagnetic Torque (Te) of the machine can be found on its description page under the Machine Section.
The following equation is used to calculate the machine power:
When the Mechanical Model Mode is set to Speed Controlled (0), the mechanical parameters (Viscous Damping, Static Friction, Inertia) are ignored. Instead, the rotor speed is directly set using the User-Defined Speed parameter, ωuser.
Choosing a Mechanical Model Mode
Select Speed Controlled mode if:
Select Torque Controlled mode if: