SCIM Local Control

This example demonstrates an open-loop control implementation for a 220-horsepower squirrel-cage induction machine. On the target FPGA, the eHS Solver simulates a three-phase, two-level inverter that drives the IM SM machine model. A unidirectional Voltage/frequency controller runs on the real-time CPU, sending gating signals to the inverter through the FPGA-based PWM Generators.

The example is available as two separate VeriStand projects, one providing support for the PXIe-7868R FPGA card and the other for the PXIe-7891 FPGA card. Both projects demonstrate the same concepts and behave almost identically.

Example Directory	<Public Documents>\National Instruments\<NI VeriStand 20xx>\Examples\OPAL-RT\Power Electronics Add-On\SCIM Local Control
Project Path	<SCIM Local Control>\Project\<NI PXIe-XXXX>\SCIM Local Control.nivsprj
Reference Documentation	IM SM

Components of the SCIM Local Control example

Opening and Deploying the Example

To avoid modifying the original example, make a local copy of the Example Directory shown above.
Open VeriStand and Browse to the VeriStand Project (.nivsprj) file at the Project Path in the copied directory.
Click Configure... to open the System Definition file.
Enter the IP Address of the Real Time target in the Controller page.
If permissions are configured on the Real Time target, enter the credentials in the Username and Password fields.
Save and close the System Definition file.
Click Operate >> Deploy.

Open the VeriStand Screen (.nivsscr) files and manipulate the parameters in the blue boxes to observe the resulting output signals. The configuration information displayed in grey is for informational purposes only; these parameters can only be modified from the System Definition file while the project is undeployed.

Controlling the Machine

Open Main.nivsscr and configure the Speed Setpoint to a value between 0 and 1800RPM. Note that the controller model used in this example is unidirectional and does not support negative speeds. Observe the Speed and Stator Current responses of the machine.

Apply a Load Torque to the machine and observe its effects on the Electromagnetic Torque and Slip.

SCIM operation at 1600RPM with 1000Nm of torque applied.