PLECS 3.7 Online Help

Thermal Library

PLECS uses a library of thermal data sheets for semiconductors. The data sheets of the thermal library are created and edited with the thermal editor (see Thermal Editor). By separating the thermal descriptions of semiconductors from their electrical behavior it is possible to use specific parameters from semiconductor manufactures for thermal simulations in conjunction with the generic electrical switch models from PLECS.

Library Structure

PLECS uses directory names to hierarchically organize the data sheets in the thermal library. The reference to a data sheet consists of its relative path and its filename starting from the directories on the thermal search path.

The search path for thermal libraries is specified in the PLECS preferences (see section Configuring PLECS). Each search path entry is the root directory for a library tree. On program startup PLECS searches each root directory in the search path recursively for .xml files and merges the available descriptions into one logical structure. The accessible data sheets can be updated manually by pressing the Rescan button in the PLECS preferences window. If a new data sheet is created and saved below a directory which is already on the search path the library is updated automatically.

A common way to organize data sheets within a thermal library is to use the manufacturer name as the first directory level and the part number as the filename of the data sheet.

Global and Local Data Sheets

In addition to the global library search paths specified in the Preferences window PLECS searches a private directory for each model. This allows for sharing models with other users without the need to synchronize the whole thermal library. The private directory is located in the same directory as the model file. Its name is the name of the model file (without the .mdl extension) plus a suffix _plecs, e.g. plSMPS_CCM_plecs for model plSMPS_CCM.mdl.

If a library file with the same relative path is found both in the global and the local library the file from the local library is used.

Creating New Data Sheets

New thermal data sheets are created by selecting New... + Thermal description... from the File menu.

The data sheet should be saved on the thermal search path, otherwise it will not be added to the thermal library and cannot be accessed.


Note  It is also possible to import thermal descriptions from PLECS 1.x using the command line interface (see section Command Line Interface).

Browsing the Thermal Library

PLECS allows for browsing the thermal library with the Thermal library browser. It is invoked from the View menu.

The tree view on the left shows all local and global data sheets of the thermal library for the current model.