Plexim have released a new “thermal Import Wizard” feature for the PLECS power simulation platform. This allows users to generate thermal descriptions by importing graphs from a product datasheet when a PLECS model of a semiconductor device is not available from the manufacturer. The user saves the graph as a bitmap file and imports into PLECS.
There is a tutorial video demonstrating the thermal import wizard here.
How to use the PLECS thermal import wizard
There is already an extensive library of thermal models for a range of semiconductor devices from various manufacturers. However, for devices which are not already in the library it is now possible to import the graph (or raw data) from a datasheet and PLECS will interpolate the graph to generate the thermal model itself. .
- Open a new PLECS model
- Save the screenshot as a bitmap file.
- Drag and drop the screenshot into the wizard. A configuration window pops up automatically.
- Enter the min and max limits.
- Define a few datapoints for the switching losses (see red line and datapoints in the below screenshot).
- If necessary change the voltage and temperature values for the lookup table.
- PLECS will use linear interpolation to generate the thermal data from the graph.
- You can import as many graphs as needed.
Alternatively data can be entered manually into tables using a formula based approach.
Thermal models are already avilable for IGBT modules, fast recovery diodes, MOSFETs, SiC power modules and and discrete IGBTs from most semiconductor manufacturers including ABB, Dynex, GaN Systems, Infineon, Rohm and Wolfspeed.