emtiop 1.0.1

3743

IEEE Std P3743, Recommended Practice for Electromagnetic Transient Model Interoperability for Electric Power Transmission Systems, has the purpose of building and maintaining electromagnetic transient (EMT) models of electric power transmission systems. The EMT models require input from different existing sources of data for power flow, short circuit and positive sequence dynamics, supplemented with new data source definitions. This recommended practice applies to offline and real-time EMT simulation tools. It does not apply to EMT models of electric power distribution systems, nor to positive sequence dynamic models of either transmission or distribution systems.

The first version of IEEE Std 3743 has been developed in 2025-2026, responding to a series of white papers from the NERC EMT Working Group. In a Reliability Guideline NERC identifies a critical need for accurate and efficient EMT studies to maintain electric power grid reliability, especially with inverter-based resources (IBR). NERC further identifies dynamic link library (DLL) models of IBR controls, based on the real hardware control code, as a preferred method of obtaining accurate EMT simulation results with IBRs.

Another IEEE Std P3597, Standard for Interfacing of Controls and Protection to Power System Simulation Tools, began work in July 2026 to standardize a DLL application program interface (API) for EMT simulations.

This open-source software helps users of P3743 and P3597 create and maintain interoperable EMT models. It incorporates extensions and profiles of the Commoon Information Model (CIM), tailored for EMT studies. It builds on open-source CIM available from the CIM Users Group under the Apache 2.0 license. It includes examples, test cases, and scripts that may help others implementing P3743 and P3597.

Documentation and Installation

On-line Documentation is maintained from source files in this repository.

A scripting package that supports P3743 may be installed using the command pip install emtiop

Leadership

• IEEE P3743 Working Group Chair: Tom McDermott, t.mcdermott@ieee.org
• IEEE P3743 Working Group Vice-Chair: Chavdar Ivanov, chavdar.ivanov@griddigit.eu
• IEEE P3743 Working Group Secretary: Meghana Ramesh, meghana.ramesh@pnnl.gov
• Open Source Lead: Tom McDermott, t.mcdermott@ieee.org
• Open Source Maintainer: Prabhpreet Dua, prabh.dua@gmail.com

IEEE Std. 3743 and this open-source project are sponsored by the IEEE PES Analytic Methods for Power Systems (AMPS) Committee. The Standards Coordinator for AMPS is Chris Dent, Chris.Dent@ed.ac.uk

Disclaimer Notice

This IEEE Open Source Project contains material that may be included in, or referenced by, an unapproved draft of a proposed IEEE Standard. All material in this Project is subject to change. The material in this Project is presented “as is” and with all faults. Use of the material is at the sole risk of the user. IEEE specifically disclaims all warranties and representations with respect to all material contained in this Project and shall not be liable, under any theory, for any use of the material. Unapproved drafts of proposed IEEE standards shall not be utilized for any conformance/compliance purposes.

Apache License Notice

Copyright 2026 3743 Authors

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

See the LICENSE file distributed with this work for copyright and licensing information, the AUTHORS file for a list of copyright holders, and the CONTRIBUTORS file for the list of contributors.

SPDX-License-Identifier: Apache-2.0

See the LICENSE file distributed with this work for copyright and licensing information, the AUTHORS file for a list of copyright holders, and the CONTRIBUTORS file for the list of contributors.