Large-Scale Electromechanical Power System Real-Time Simulation

ePHASORSIM: OPAL-RT’s transient stability simulator for large-scale T&D systems. Power Grids are increasingly stretched beyond their limits by renewable energy sources, overloaded networks, and cybersecurity requirements. This dramatically increases the operational complexity and control/protection of these grids. ePHASORSIM offers in-depth analysis to simulate, test and maintain these networks, with significant time and money savings.

ePHASORSIM simulates power systems at a few-millisecond timestep and excels at testing/integration of EMS/SCADA systems, precise HIL simulation of large-scale networks, wide area protection and control schemes (WAMPAC), as well as operator training and power system studies. Its phasor domain solver performs transient stability simulation analysis–such as voltage/current magnitude and angle, power transfer, and machine speed–as accurately as phasor measurement units (PMU) installed on the power grid.

Real-Time Simulation of 100,000+ Nodes of T&D Systems

ePHASORSIM Helps Power Labs and Research Facilities to Focus On:

  • Real-time transient stability simulations for systems in range of 30,000 nodes
  • Wide-area control/protection/state estimation algorithms
  • EMS tools and algorithms, such as AGC and load shedding
  • PMU streams and PDC applications
  • System studies with massive numbers of renewable penetration
  • Design and test local controllers, such as voltage regulators
  • Advanced metering and information network
  • Impact of load profiles in distribution networks

The Integrated Environment of ePHASORSIM


ePHASORSIM real-time simulation is performed under the OPAL-RT’s flagship RT-LAB simulation platform. It allows ePHASORSIM to be connected as part of a larger Simulink model, enabling researchers to benefit from a complete grid ecosystem, as well as having access to all OPAL-RT hardware modules and I/O and communication protocols such as DNP3, OPC-UA, C37.118 and interconnect the real time simulation with physical devices under test. The platform also offers all features for monitoring, data processing and data acquisition to facilitate testing, analysis and reporting. ePHASORSIM could also be connected to other third party software such and ETAP, RTDMS, openPDC, and Kepware to send measurement data and receive control or operation commands.


Porting an existing simulation of a large grid model with thousands of buses represents a great deal of work, with no guarantee of research value. Designed to accelerate real-time simulation and maximize research time, ePHASORSIM imports simulation models of the most important third-party simulation offline tools, including ETAP, PSS®E, DIGSILENT and CYME.

A collection of models for positive sequence as well as three-phase unbalanced power grids is provided in library of ePHASORsim. The library includes models of generators and their controllers, loads, transformers, current injector devices and voltage sources, along with a various types of events associated with each component to simulate complex operating and control scenarios in real-time. In addition to the basic supported blocks, ePHASORSIM is expandable to new user defined components and functionalities based on Modelica’s Functional Mockup Interface (FMI) and Simulink/SimScape Power System toolboxes.


Perform thousands of tests automatically with ePHASORSIM's versatile API, enabling on-the-fly validation of different sets of parameters in the model. Automation tests are easily performed using PYTHON or C-family languages.

High Performance

ePHASORSIM allows the simulation of massive grids going up to 20k buses on a single core computer and its capability of performing parallel computing allowing unleashed performances for larger grid real-time simulation and offline simulation. Systems in the range of 50k to 100k nodes can be simulated for test and prototype of sophisticated operation scenarios. No matter of type, balanced or unbalanced, ePHASORSIM can perform real-time transient stability simulation with a time-step of a few milliseconds.  The parallel simulation feature goes much beyond by allowing to run multiple simulations of one or different power grids that each of them are associated with an individual operating scenario. This feature, easily can provide up to 32x speedup of a dynamic simulation on a 32 core real-time simulator.


Simulation type:Phasor domain
Typical time step:1ms - 10 ms
Compatible modeling environments: Simulink, Excel, ETAP, PSS®E, CYME, Power Factory, FMU (Open Modelica)
Maximum real-time network size:30,000 nodes
Maximum non real-time network size:100,000 nodes
Capability per CPU core:10,000 nodes @ 10 ms
Features:• Positive sequence and unbalanced networks
• Load flow (positive sequence)


Wide-Area Monitoring, Protection and Control

Develop new control and measurement algorithms for Wide Area Monitoring, Protection and Control (WAMPAC) applications.


Learn how real-time simulation is employed as a powerful and efficient testing tool, by simulating real-world cyberattacks and system failures in a controlled environment.

Operator Training

ePHASORSIM is the core software for operator training simulators for transmission systems using balanced positive-sequence network models, and for distribution systems using unbalanced phase-by-phase network models.

Customer Success Stories

L2EP have designed distributed energy test platform with an advanced metering infrastructure to assess electric vehicle supervision strategy influence.

Download PDF

Fraunhofer IWES’s development of a novel real time EV-fleet simulator for studying potential grid impacts and grid integration strategies of large EV fleets.

Download PDF

TNB Research uses a real-time simulator for WAMPAC studies who has the capability to simulate 1500 single-phase electrical nodes with individual control of breakers and transformer tap changers.

Download PDF

Related Resources