Stability Analysis Functions (RMS)

The RMS simulation tool in PowerFactory can be used to analyse mid-term and long-term transients under both balanced and unbalanced conditions, incorporating a simulation scan feature.  DIgSILENT Simulation Language (DSL) is used for model definition, and a large library of IEEE standard models is available. Flexible co-simulation options are also available.

  • Multi-phase AC networks, DC networks
  • Support of balanced and unbalanced grid conditions
  • Fast, fixed step size and adaptive step size algorithm
  • A-stable numerical integration algorithms supporting long-term stability simulations with integration step sizes ranging from milliseconds to minutes, individually selectable for each model
  • High precision event and interrupt handling
  • Simulation of any kind of fault or event
  • Transient motor starting (synchr./asynchr. machines)
  • Support of all protection library relays
  • Real-time simulation mode
  • Simulation scan feature, e.g. frequency scan, loss of synchronism scan, synchronous machine speed scan, voltage-/voltage recovery scan, fault ride through scan or common variable scan
  • Frequency Analysis Tool, including Fast Fourier Transform (FFT) and Prony Analysis for single point in time as well as time-range assessment
  • Frequency Response Analysis tool for dynamic models with Bode/Nyquist plots

User-Defined Dynamic Models (UDM)

  • High-level UDM Representation
    • Graphical modelling environment for the development of UDMs
    • Support of native models (inbuilt elements, DSL and Modelica), as well as externally-interfaced models (FMI and IEC 61400-27)
    • Support of highly scalable concepts for deployment of UDMs in large power networks using Composite Model Frames and Composite Models
    • Access to input/output signals of any network element
    • Support of scalar and vector based signals as well as various signal multiplexing options for easy distribution of signals from/to many components
    • Nesting of Composite Model Frames enabling complex system architectures e.g. interfacing between dispatch center controls, power plant controls and subordinated power equipment components
    • Inbuilt support for creation of user-defined power electronics topologies for EMT Simulation via submodels
    • Support of complete power equipment models: easily pack, export, import and deploy complex UDMs using General Templates
  • DIgSILENT Simulation Language (DSL)
    • Graphical modelling environment for development of complex DSL models
    • Large inbuilt library of DSL macros for simplified creation of block diagrams
    • Support of complex non-linear time-continuous control models including advanced functionality e.g. step size independent solution, instantaneous event triggering, fast simulation options
    • Inbuilt editor for coding user-defined DSL models using DIgSILENT Simulation Language
    • Large inbuilt standard model library, including IEEE, IEC, WECC and CIM ENTSO-E models
    • Automatic initialisation of complex, non-linear models
    • Configuration script for initialisation using DPL
    • Compilation of DSL models into DLLs for improved simulation performance
    • Option for automatic compilation of DSL models
    • DSL Encryption function1 for protection of intellectual property data when using non-compiled (open) DSL models
  • Modelica Simulation Language
    • Graphical modelling environment for development of complex Modelica models
    • Inbuilt library of Modelica basic blocks for simplified creation of models containing hierarchically structured block diagrams
    • Support of time discrete (clocked) control models including array signals and variables, sequential algorithms and selectable data types
    • Inbuilt editor for coding user-defined models using Modelica Language
    • Hierarchical parameter structure for Modelica models
    • Configuration script for initialisation using DPL
    • Export Modelica model using the FMU Export function2
  • Interfaces for Dynamic Models
    • Import external models using Functional Mock-up Interface (FMI 2.0 for Co-Simulation, FMI 2.0 for Model Exchange)
    • Import external models using IEC 61400-27 DLL C-interface
    • Communicate with external components using the OPC interface3 or various applications (e.g. real-time simulation)
    • Communicate with external components using the IEEE C37.118 simulation interface4 for PMU data streaming

Co-Simulation Functionality

  • Single domain co-simulation (RMS balanced – RMS balanced, RMS unbalanced – RMS unbalanced, EMT - EMT5)
  • Multiple domain co-simulation (RMS balanced – RMS unbalanced – EMT5)
  • Co-simulation with external solver6 (e.g. third party power systems ­simulation program) using FMI 2.0 (Functional Mock-Up Interface)
  • Computing supported as built-in for increased performance
  • Both accurate (implicit) and fast (explicit) co-simulation methods ­available
  • Support of multi-port Norton/Thevenin remote network equivalents for explicit method
  • Easy to define co-simulation border using boundary objects
  • Any number of co-simulation regions can be defined
  • Co-simulation of networks split by regions depending on any criteria: localisation, voltage levels, etc.


1 Licence for DPL/DSL/QDSL encryption required. Encryption Function licence. DIgSILENT does not give any express warranties or guarantees for cryptographic security of encrypted models. In particular, DIgSILENT does not guarantee that the details and functionalities of an encrypted model are secure against all means of access or attack attempts.
2 Requires FMU Model Export licence
3 OPC interface licence required
4 C37 Simulation Interface licence required
5 EMT licence required
6 Requires separate Co-Simulation Interface licence