Release Notes

Version 4.5 – January 15, 2021

  • The new FMU block enables you to include Model-Exchange Functional Mockup Units created by other simulation tools in your PLECS models.
  • There are two new Phase Locked Loop implementations: PLL (Single-Phase) and PLL (Three-Phase).
  • The new Multiport Signal Switch allows you to switch between multiple signals depending on a control signal.
  • The new Dynamic Signal Selector allows you to select or reorder elements of a vector signal depending on a control signal.
  • The Integrator has been enhanced with an option to wrap the integrator state between given limits.
  • The Transport Delay has been enhanced with an option to specify the delay time with a control signal instead of a parameter.
  • You can now configure PLECS to show link indicators on components that link back into a library.
  • The Generic PLECS Coder target has been enhanced with an option to create separate output and update functions instead of a single step function.
  • PLECS Standalone has a new default variable-step solver auto that automatically switches from the non-stiff DOPRI solver to the stiff RADAU solver if a model is found to become stiff during a simulation.
  • The new Model Reference block in PLECS Standalone allows you to reuse a subsystem from one model in another model via a link so that the referencing subsystem is updated automatically when the original subsystem is changed.
  • The new solver option OutputTimes enables you to specify the time values for which you wish to retrieve output signal values when running a simulation from an Octave script or via the XML-RPC interface.
  • PLECS Blockset now has a Demo Mode analogous to the Demo Mode of PLECS Standalone. The Demo Mode allows you to use PLECS without a license. You can freely edit models and run simulations, but saving models is disabled.
  • PLECS Blockset now supports the “Fast Restart” feature of Simulink.

Version 4.4 – June 5, 2020

  • The PLECS Coder has been enhanced with the capability to generate code for multi-tasking systems.
  • PLECS now supports non-floating-point signal data types for normal simulations. Data types were introduced in PLECS 4.2 for code generation only; the same data types are now used also during normal simulations.
  • The algorithm used to discretize state-space matrices for use with a fixed-step solver, BI45, has been replaced with Radau IIA.
  • The output ports of triggered and/or enabled subsystems now have an “Initial output” parameter that lets you configure the output values before the first execution of a subsystem.
  • The Scope and the XY-Plot let you display a legend on top of the plots for easier identification of signals without having to show the data widget.
  • Subsystems can now be easily converted to configurable subsystems via a context menu “Convert to configurable subsystem”.
  • The Library Browser has been enhanced with a quick access feature that lets you insert components in a schematic window without having to change to the Library Browser window.
  • The new From File block reads signal trajectories from CSV or MAT files.
  • There are two new configurable Continuous and Discrete PID Controller blocks with optional anti reset-windup.
  • The new filter blocks Fourier Transform, RMS Value and Total Harmonic Distortion provide dual implementations in the continuous and discrete time domain for efficient simulation both with a variable-step and a fixed-step solver.
  • The Power Modules library has been extended with new models: 3-Level Half Bridge (ANPC), 3-Level Half Bridge (T-Type), 5-Level Half Bridge (ANPC), 3-Phase Current Source Inverter, 3-Phase Voltage Source Inverter, Dual Active Bridge Converter, Flying Capacitor Half Bridge, Full-Bridge LLC Resonant Converter, Half-Bridge LLC Resonant Converter, Phase-Shifted Full-Bridge Converter
  • The To File block has a new parameter “Write signal names” that lets you choose whether CSV files are written with a header row containing the names of the input signals.
  • The Rate Limiter has a new parameter “Sample time mode” that lets you choose whether the block operates with a continuous sample time or whether the sample time is inherited from the input.
  • The Octave engine shipping with PLECS Standalone has been updated to version 4.4.1. The new version supports graphical output (e.g. plot, surface) on all platforms and includes the Signal and Control toolboxes.

 Version 4.3 – June 17, 2019

  • The new Import Wizard of the thermal editor facilitates the import of data from graphs. The wizard also includes a fitting algorithm to calculate Foster network coefficients for the thermal impedance from heating curves.
  • The Target Support Package framework of the PLECS Coder has been extended to facilitate code generation and external mode operation for embedded targets.
  • The Monoflop and Turn-on Delay now have an option to specify the pulse duration resp. delay time via a control signal instead of a parameter.
  • The dialog callback of a masked subsystem lets you hide, show and move subsystem terminals depending on mask parameters.
  • The schematic editor now has two additional zoom modes: For smooth zooming hold the Ctrl key (cmd on macOS) while turning the scroll wheel on the mouse. To fit the entire schematic into the editor window, select Zoom to fit from the View menu or press Ctrl-* (cmd-* on macOS).

 Version 4.2 – August 31, 2018

  • The schematic editor has been enhanced with a smart routing algorithm that reduces the occurrence of overlapping connections. The new autoconnection feature lets you quickly create connections between two or more components.
  • PLECS now lets you create dynamic mask icons for masked subsystems that can change their appearance depending on parameter settings. You can also create dynamic dialogs by disabling or hiding a parameter or changing its value depending on the value of another parameter.
  • The PLECS Coder has been enhanced with the support of non-floating-point signal data types.
  • New scripting commands provide new methods to interact with PLECS Scopes. You can set cursor positions and query cursor data, and export curves as CSV files or bitmaps.

Version 4.1 August 11, 2017

  • PLECS has been extended with the capability to solve algebraic loops. Several new components make use of this feature: Algebraic Constraint, Variable Resistor, Electrical Algebraic Component, Rotational Algebraic Component and Translational Algebraic Component.
  • The State Machine has been enhanced with Junctions and Time-based Triggers.
  • For fixed-step simulations of physical models, a new discretization method with better accuracy and damping has been implemented as an alternative to the previously used Tustin method.
  • The PLECS Coder for PLECS Blockset is now also capable of producing code for the PLECS RT Box. Also, the External Mode can be used in PLECS Blockset to connect a PLECS model with an application running on a hard- ware target in order to tune parameter values on the target and display captured data in the PLECS model.
  • The State Space and Discrete State Space blocks have been enhanced to accept an empty A matrix (in which case the B and C matrices must also be empty). The blocks will then act like matrix gains.
  • When running simulations or analyses from a simulation script in PLECS Standalone, you can specify a timeout after which a simulation or analysis will be forcibly stopped.
  • The new command plecs (’warning’, ’message’) can be used in initialization commands to report warning messages to the Diagnostics window.
  • The mask icon drawing commands for subsystems now accept comments.

Version 4.0 – July 8, 2016

  • The new State Machine block provides a modeling environment for finite state machines that respond to discrete events.
  • The electrical machines library has been extended with new synchronous machine models based on look-up tables that can be imported from an FEM tool. The Induction Machine with Saturation now features a “Full VBR” implementation, in which both the stator and the rotor are modeled as voltages behind variable reactances.
  • The mechanical library has been extended with a Planetary Gear Set.
  • PLECS can now automatically calculate initial temperatures for thermal capacitances based on their ambient temperature.
  • The Processor-in-the-Loop framework has been extended to support STM32 F0, F1, F2 and F3 MCUs.
  • The PLECS Coder for PLECS Standalone has been extended with the capability to produce code for a specific hardware target. The new External Mode enables you to connect your PLECS model with an application running on a hardware target in order to tune parameter values on the target and display captured data in the PLECS model. The first supported hardware target is the PLECS RT Box.
  • In PLECS Blockset, continuous inputs of a Circuit block that do not have an immediate effect on any output are marked as “non-direct feedthrough” inputs. This helps reduce the occurrence of algebraic loops, e.g. if you model a mechanical load in Simulink by measuring the rotor speed of a machine in a Circuit block and feeding the load torque back into the same Circuit block.
  • The graphical user interface of PLECS now supports high-DPI displays on Windows and Mac OS X.
  • The help viewer now provides a full-text search engine.

Version 3.7 – July 20, 2015

  • The thermal modeling concept of semiconductor losses has been extended. Losses can now be described using functional expressions in addition to lookup tables. It is also possible to define custom parameters (such as gate resistance) and describe their influence on the device losses. Minimum and maximum values may be specified for custom parameters as well as intrinsic variables (voltage, current and temperature).
  • The PLECS Scope has been enhanced with a new „stripchart” scrolling mode and a dynamic y-axis auto-scaling method that is based on the currently visible signal values.
  • In PLECS Blockset it is now possible to create physical (i.e. electrical, magnetic, thermal and mechanical) connections between multiple PLECS Circuit blocks in a Simulink model.
  • The PLECS Standalone Coder and PLECS Blockset Coder have been unified into the PLECS Coder. In the PLECS Blockset it is now possible to generate code with or without the Simulink Coder.
  • The Processor-in-the-Loop framework has been extended to support Microchip dsPIC33F, STM 32F4 and TI 2837x dual-core Delfino MCUs. The new PIL Prep Tool simplifies the configuration of probes by parsing the source code and automatically generating configuration files. You can use the new PIL Calibrations to configure embedded control algorithms directly from PLECS. Run multiple simulations and compare results with different settings for, e.g., filter coefficients and regulator gains, without recompiling the embedded code. For a complete list of changes please refer to the release notes in the PIL User Manual.
  • The Integrator and the Discrete Integrator allow you to specify a reset value via an external signal.
  • The C-Script allows you to configure multiple input or output ports (which in turn may accept scalar or vector signals). It accepts string values to be passed in as user parameters and lets you issue custom warning messages that are logged in the diagnostics window.
  • The Sine Wave, the AC Current Source and the AC Voltage Source automatically limit the simulation step size to ensure smooth waveforms regardless of the maximum step size configured in the solver settings. The Sine Wave block is now an intrinsic component rather than a masked subsystem.
  • The parameter dialogs of the Signal From, Signal Goto and Electrical Label blocks now show a list of corresponding blocks, i.e. blocks with the same scope and tag name.
  • The PLECS Probe now features a Show component button to view the selected component in the schematic editor.
  • The new diagnostic option Division by zero controls the diagnostic action to take if PLECS encounters a division by zero during a simulation.
  • In PLECS Standalone, the analysis tools can now automatically determine the system period.
  • In PLECS Standalone, the maximum length of variable names used for mask parameters and workspace variables has been extended to 63 characters. In previous versions, the limit was 31 characters.
  • In the PLECS Blockset, the AC Sweep block and Multitone block now have a Show reference input option to facilitate the computation of transfer functions with references other than the actual perturbation.

Version 3.6 – November 3, 2014

  • Assertions allow you to monitor arbitrary signals during a simulation and raise a warning or error message if they fail to meet a given condition.
  • The new Multitone Analysis provides a fast alternative to an AC Sweep.
  • The new Processor-in-the-Loop framework - licensed separately - enables you to test control code executed on an external processor tied into the virtual world of a PLECS model. 
  • PLECS Web-Based Simulation - licensed separately - lets you share a PLECS model via the web. Models can be viewed, parameterized and simulated from any web browser without the need to download additional software.
  • Code generation now provides an enhanced switching algorithm for naturally commutated devices yielding a uniform execution time for simulation steps with or without switching events.
  • Tabbed dialogs enable you to design clearly arranged dialogs for masked subsystems that require a large number of mask parameters.
  • The new Power Module blocks are useful to create multilevel converter applications with a configurable number of voltage levels. They feature both a switched and averaged implementation, the latter being particularly well suited for real-time simulations with high switching frequencies.
  • Further new blocks have been added to the library: Discrete Integrator, Pause / Stop, Compare to Constant, Offset, Manual Switch, Manual Double Switch, Manual Triple Switch, Manual Signal Switch.
  • The XY-Plot can now display vectors in addition to or instead of trajectories.
  • The To File block allows you to specify the output file name as a literal string or via a string variable.
  • The Function block is resizable to display the function expression in the block icon.
  • The Ideal Transformer has an optional intrinsic magnetizing inductance.
  • The following blocks let you specify a pulse duration respectively delay time of 0 in order to deactivate them without having to remove them from the schematic: Monoflop, Turn-on Delay, Blanking Time, Pulse Delay, Transport Delay.

Version 3.5 – January 8, 2014

  • Certain parameters can be changed while a simulation is running.
  • Code generation now supports naturally commutated devices, such as diodes and thyristors, and control blocks with a discrete sample time.
  • The Enable block permits the conditional execution of subsystems containing control blocks.
  • New blocks have been added to the PLECS Library: Discrete State Space, White Noise Generator, Random Number Generator and 3-Level Space Vector PWM.
  • The circuit browser can display all components of a model in a hierarchical or flat view.
  • If multiple components of the same type are selected, their parameters can be changed simultaneously.
  • The Constant, Transfer Function and Discrete Transfer Function blocks are resizable to display their parameters in the block icon.
  • PLECS can be enabled to automatically check for updates.
  • The XY Plot can be set to a fixed aspect ratio.
  • In the thermal editor the user can exchange data with other applications, such as Microsoft Excel, using copy and paste. All thermal data can be scaled conveniently.
  • The C-Script editor now supports “Find and Replace”.

Version 3.4 – June 14, 2013

  • A mechanical domain has been introduced featuring one-dimensional translational and rotational motion.
  • All of the machine components have been updated to include a mechanical flange for connecting a shaft.
  • The two synchronous machine models now offer a full voltage-behind- reactance implementation allowing the connection of arbitrary circuits to the field winding as well as the stator windings.
  • With the Trigger block, a subsystem comprising signal processing blocks can be executed in an event-driven fashion.
  • The new 3-Phase Transmission Line models long power lines either as series-connected pi sections or with distributed parameters.
  • Code generation is now also available for PLECS Standalone. 
  • A status bar has been added at the bottom of the PLECS schematic window for displaying warning and error information.
  • PLECS Standalone can be used in a demo mode without a license file. In this mode, certain models can be opened and simulated but not saved.

Version 3.3 – July 6, 2012

  • The Magnetic library allows the user to include magnetic designs for inductors and transformers in the simulation model. 
  • Color and other curve properties of the PLECS Scope can now be customized. 
  • Trace data can now be saved and loaded into a PLECS Scope.
  • Multiple overlaying signals can automatically be separated in the PLECS Scope.
  • The state space matrices can now be accessed also in PLECS Standalone.
  • New components were added to the PLECS library: Moving Average, Periodic Average, Periodic Impulse Average.
  • The behavior of a PLECS Probe during copy operations has changed.
  • PLECS Standalone for Mac OS X is now a 64-bit application. Existing shared libraries for use with the DLL block must be recompiled for 64-bit support.

Version 3.2 – September 15, 2011

  • The PLECS Scope allows you to show multiple traces to compare results from different simulation runs. 
  • In PLECS Standalone, simulations and analyses can be parameterized and run from a simulation script. 
  • The DLL block allows you to interface external DLLs with PLECS. 
  • New components were added to the PLECS library: The Space Vector Modulator, Discrete Transfer Function, SR Flip-flop, D Flip-flop, JK Flip-flop, Monoflop, Quantizer, Rate Limiter, 3 phase AC Voltage Source and 3 phase Meter.
  • The Permanent Magnet Synchronous Machine has two implementations: The traditional rotor reference frame model and a new voltage behind reactance model.
  • The discrete analysis blocks can now be used in a PLECS Circuit directly and are also available in PLECS Standalone.

Version 3.1 – December 7, 2010

  • New components were added to the PLECS library: XY Plot, To File, Electrical Label, Signal From, Signal Goto, Transport Delay, Discrete Transport Delay and Turn-on Delay. 
  • Two different implementations for synchronous machine models and the Induction Machine with Saturation are now selectable: The traditional rotor/stator reference frame model and the new voltage behind reactance model. 
  • The Small Signal Analysis Tools are now available in PLECS Standalone. 
  • The modulator blocks can now be used in a PLECS circuit directly and are also available in PLECS Standalone.
  • A Fourier spectrum can be generated from the PLECS Scope. 
  • The number of inputs, outputs and states in the C-Script block can now be set dynamically. Compilation errors from the C-Script block are visualized in the editor. 
  • User libraries can be added to the Library Browser. 
  • For model initialization in PLECS Standalone it is now possible to set initial conditions and model initialization commands. 
  • A grid can be displayed in PLECS schematics. 

Version 3.0 – February 18, 2010

  • In addition to the traditional Simulink-based version, PLECS Standalone is now available as a separate product. Using dedicated solvers, it offers even faster simulation results.
  • New components were added to model control structures directly in PLECS: Clock, Step, Pulse Generator, Ramp, Sine Wave, Triangular Wave, Gain, Sum, Product, Abs, Signum, Relational Operator, Logical Operator, Trigonometric Function, Math Function, Transfer Function, State Space, Delay, Zero-Order-Hold, Memory, Saturation, Dead Zone, Relay, Signal Switch, Hit Crossing, Comparator, Combinatorial Logic, Polar to rectangular and Rectangular to polar transformation.
  • The C-Script block makes it possible to implement custom components in PLECS using the C programming language.
  • The new Library Browser allows easy access to the component library. Components can be searched in the browser to make access much faster than before.
  • If an electrical component with two terminals is moved onto an existing connection, the connection is split up and the component is inserted automatically.
  • PLECS no longer uses different connection types for continuous signals and gate signals. This distinction is made only in the Signal Inport when importing a signal from Simulink into a PLECS circuit.
  • The Variable Capacitor and Variable Inductor and related components can now be freely interconnected. 
  • Component names are no longer displayed in the component parameter dialog. They can be shown and hidden using the components context menu.

Version 2.2 – June 29, 2009

  • The extended code generation of PLECS now supports the Real-Time target in addition to the Rapid Simulation target.
  • The Configurable Subcircuit allows to exchange the implementation of a Subcircuit by parameter.
  • The Piecewise Linear Resistor allows to specify the behavior of non-linear resistors.
  • The data analysis in the PLECS Scope now allows to calculate the total harmonic distortions (THD).

Version 2.1 – December 22, 2008

  • The PLECS Scope is a convenient tool for viewing simulation results. It offers advanced zooming and panning features and cursors for reading data values and measuring time differences. It can perform simple analyses such as obtaining the RMS value of a signal. 
  • The code generation capabilities of PLECS enable you to use Simulink’s Rapid Accelerator mode, the rapid simulation (RSim) target and the S- Function target of the Real-Time Workshop with models containing PLECS blocks. 

Version 2.0 – April 3, 2008

  • The schematic editor was completely rewritten to allow for faster and better interaction.
  • Unlimited undo/redo capabilities in the schematic editor.
  • New editor and library concept for thermal descriptions. 
  • New analysis tool: Impulse Response Analysis. 
  • The preferences are no longer stored in a text file; they can be edited in the Preferences window. 
  • PLECS schematics can be exported to bitmaps or PDF files. 
  • New components in the Switches library: Reverse Blocking IGCT, Reverse Conducting IGCT, GTO with Diode.
  • New thermal component: Thermal Chain.
  • Enhanced PWM blocks to allow for time shift of carrier: Symmetrical PWM, Sawtooth PWM, Symmetrical PWM (3-Level) and Sawtooth PWM (3-Level).
  • Dynamic width propagation for vectorized components and connections.
  • PLECS is available in English and Japanese.

Version 1.6 – August 7, 2007

  • New analysis tools enable you to quickly determine the periodic steady state of a power electronic system, to perform ac analyses and to extract the state-space matrices of a circuit model.
  • New advanced behavioral semiconductor models: Thyristor with Reverse-Recovery, IGBT with Limited di/dt, MOSFET with Limited di/dt.
  • New components in Signals & Systems: Continuous Selector, Gate Selector, Wire Selector.
  • Additional vectorized components: Saturable Inductor, Saturable Capacitor, 1D Look-Up Table, 2D Look-Up Table, 3D Look-Up Table.

Version 1.5 – December 12, 2006

  • The Thermal library enables you to include the thermal design with the electronics design of your power circuit. 
  • The PLECS Viewer lets you share your circuit models with users that do not have a license for PLECS. 
  • The simulation parameter "Refine factor" of the Discrete State-Space Method allows you to simulate the discretized circuit model with a smaller time step than the Simulink model. 
  • Enhanced three-phase transformer models for three-leg and five-leg transformers including saturation: 2-Winding 3-Phase Transformer, 3-Winding 3-Phase Transformer.
  • New machine model: Simple Brushless DC Machine.
  • New semiconductor model: Zener Diode.
  • New function block: 3D Look-Up Table.

Version 1.4 – June 19, 2006

  • New saturable machine models: Saturable Induction Machine, Salient Pole Synchronous Machine, Round Rotor Synchronous Machine.
  • An advanced behavioral reverse-recovery diode model.
  • Define custom probe signals for masked subcircuits. 
  • Library references enable you to ensure that your models always use the most current version of custom components from the library.
  • Additional signal blocks, e.g. the Constant Block, 1D Look-Up Table, and 2D Look-Up Table.

Version 1.3 – November 16, 2005

  • New machine models: Brushless DC Machine, Switched Reluctance Machine.
  • Additional power semiconductor models: MOSFET, MOSFET with Diode, 2-Level MOSFET Converter, TRIAC.
  • Advanced models for nonlinear passive components, e.g. Variable Resistor with Variable Series Inductor, Saturable Capacitor.
  • New components with variable number of coupled windings: Mutual Inductor and Ideal Transformer.
  • All switches can now be vectorized, e.g. Circuit Breaker.
  • Command Line Interface (CLI). 

Version 1.2 – June 23, 2005

  • Fixed time step simulations (circuit discretization).
  • Possibility to encrypt and password protect PLECS circuits.
  • Automatic creation of subcircuits.
  • Vectorized electrical wires. See Wire Mux component. Most intrinsic components can be used with vectorized wires.
  • Additional blocks and components in the PLECS library, e.g. Electrical Ground, Integrator, discretizable machines.
  • Many enhanced components in the PLECS library, e.g. Inductor.
  • Configure the graphical representation of resistors and capacitors. 
  • Possibility to change the placement of subcircuit labels. 
  • Annotations in circuits. 
  • Specify initial conditions for switch components in the component dialog.