OpenDSS Files

The Open Distribution System Simulator, OpenDSS

Copyright (c) 2008-2025, Electric Power Research Institute, Inc.
All rights reserved.

Version 10.2.0.1 - Columbus

This version is an homage to celebrate the work of the father of OpenDSS - Roger Dugan, who is retiring in 2024 after 53 years of work for the electric power industry. This software is a small part of his legacy, as well as his countless publications and other contributions to the industry.

Changes this version
====================
- Solves an issue found when using load allocation routines due to lack of sync with the solution actor (it's been there probably for a while).
- RegControl: added flags (idle, idleReverse, idleForward) for idling in present tap position under certain flow conditions. This behavior is typical in regulator controls around the no-load zone (-revThreshold < kW < +revThreshold) or in the forward (kW> +revThreshold) or reverse (kW<-revThreshold) flow zones for certain reverse operation modes (Bi-directional, Locked Forward, Locked Reverse, Reverse Idle). The existing operation of the RegControl doesn't change if flags are left on their defaults. Also updated the description of the "reversible" property to fit this update.
- Fixes issue at DLL (Delphi) when retrieving the Y value based on X.
- Adds verifications when getting the pointer for the next reactor. Applies for COM and DLL.
- Fixes issue with AllowForms assignment (DLL/COM) in both platforms (C and Delphi).
- Fixes issus introduced in v 10.1.0.1 preventing A-Diakoptics to work properly.
- DSSpyServer updated for working under Linux and Windows environments.
- Introduces the pyControl object for allowing users modeling elements in native Python. The object is integrated into the simulation as a python script. 
- Fixes issues in COM and DLL affecting XYCurves [r4007] and Allocation factor [r4008]. 

C++:
- "UserManual" command triggers the online user manual in both, Windows and Linux.
- The program is compatible with gedit for displaying reports. If want to use it, install gedit in Linux using "sudo apt-get install gedit".
- The program supports pyControl objects in Linux and Windows. For enabling debugging in Linux, install xterm (sudo apt-get install xterm).


v 10.1.0.1
- Provides better sync between actors and main thread through queues preventing polling.
- Includes the property SemiConLayer the declare the existence of a semicon layer for CNData/LineGeometry objects.
- Improves the sync with the progress bar app.
- Removes over estimation (Size) for IBR working in GFM mode for better exposing the short circuit features of the model.

v 10.0.0.2
- Solves a bug found when reporting powers for generators while using NCIM solution mode.
- Adds interfaces in COM / DLL for directly handling Storage and WindGen objects.

v 10.0.0.1
- Adds the WindGen object for modeling wind generators in QSTS and dynamics domains.
- Introduces the NCIM solution method for handling transmission circuits that can be difficult to solve with the other methods already available in OpenDSS.
- Implements corrections in COM / DLL for recently noticed bugs found around.

The Version 8 was the first to be delivered with parallel processing capabilities in both 32-bit (X86) and 
64-bit (X64) versions. Version 9 is the latest update. The files are still listed under the 'Version8' folder on Sourceforge.net.
The OpenDSSInstaller download includes both X86 and X64 versions of Version 9, along 
with optional documentation and examples.  

If you have 64-bit Windows, you may install both the 64-bit and 32-bit 
versions.  The 32-bit version is required if you plan to automate OpenDSS 
from Excel or any other 32-bit program.  The 64-bit version is required to 
automate OpenDSS from 64-bit MatLab or other 64-bit apps on a 64-bit system.  

Installation
============

The installer will give you a choice to install the executables and 
optional files under a target directory of your choice, such as 
c:\opendss.  Files that are specific to the 32-bit version will be written 
to an x86 subdirectory, such as c:\opendss\x86.  Files that are specific 
to the 64-bit version will be written to an x64 subdirectory, such as 
c:\opendss\x64.  The EXE and DLL files should not be moved after 
installation, but may be updated in place with newer versions.
  
On a 64-bit system, you may install and use both the 32-bit and 64-bit 
versions with no conflict between them.  

Short-cuts to the program and manual are created under Start Menu/OpenDSS.
Please see the manual, OpenDSSManual.PDF, for an overview of the program. 
The most up-to-date reference information will always be found through the 
software's "Help / DSS Help" menu command.

If you have an earlier version of OpenDSS installed and registered, such as 7.4.3,
remove it completely. Otherwise, Windows may retain a registry entry to the
old 32-bit COM server when you start it up from a 32-bit program.

COM Automation
==============

The COM Server in OpenDSSEngine.DLL may be automated.  The installer will 
register either or both versions, depending on your selection.  Even 
though the file names and registration commands match, they are in 
separate locations and Windows will activate the correct version required 
by the calling program.  For example, 64-bit MatLab will call the 64-bit 
OpenDSSEngine.DLL and 32-bit Microsoft Excel will call the 32-bit version.  
(Note: The 64-bit version of Excel is rarely installed.) 

Background
==========

The OpenDSS is a simulator specifically designed to represent electric 
power distribution circuits.  OpenDSS is designed to support most types of 
power distribution planning analysis associated with the interconnection 
of distributed generation (DG) to utility systems.  It also supports many 
other types of frequency-domain circuit simulations commonly performed on 
utility electric power distribution systems.  It represents unbalanced 
conditions, stochastic processes, and other aspects of electrical power 
distribution systems and equipment in far greater detail than many other 
tools, including commercial products.  Through COM and scripting 
interfaces, other programs can drive OpenDSS in highly customized 
simulations, Monte Carlo analysis, etc.  Users can define their own models 
through dynamic linking, scripting, or automation.  

Electric Power Research Institute, Inc.  (http://www.epri.com) uses 
OpenDSS in its research and services work, and continues to enhance the 
software.  Earlier proprietary versions were used in dozens of studies for 
electric utility clients, and in a Web-based wind power simulator.  
There were several goals in making OpenDSS an open-source project in 2008: 

1 - Enhance the modeling capabilities available to government 
laboratories, universities, and other researchers engaged in grid 
modernization work.  

2 - Encourage interfaces between OpenDSS and complementary tools, such as 
communication system simulators or model compilers.  

3 - Encourage the adoption of items 1 and 2 into commercial products used 
by electric utilities.  

4 - Encourage collaborative efforts between industry, government, and 
university researchers in power distribution system analysis for grid 
modernization efforts.  

5 - Provide a capable testing platform for data and object modeling 
efforts currently underway in the electric utility industry.

Source Code
===========

The programming language for OpenDSS is Delphi 
(http://www.embarcadero.com), currently version Delphi 10.4 Sydney.  A free community version is available
to certain non-commercial users (see license requirements on Embarcadero site).
There is also a Free Pascal (Lazarus) version of the program.  Some of the supporting modules may 
require a C++ compiler to build from source.  OpenDSS source code is 
available from the following SVN repository: 

https://sourceforge.net/p/electricdss/code/HEAD/tree/trunk/


Third-party Components
======================

KLUSolve.DLL is open source software, available from
www.sourceforge.net/projects/klusolve

Other convenient Sourceforge.net Links
======================================

OpenDSS Download Files:

http://sourceforge.net/projects/electricdss/files/

Getting Started

http://sourceforge.net/apps/mediawiki/electricdss/index.php?title=Getting_Started

Latest Tech Notes in Wiki

Selected Tech Notes are available in the Doc Folder

Questions and Answers

Selected Q&A files are available in the Doc Folder

OpenDSS Forum

http://sourceforge.net/p/electricdss/discussion/861976/

What is Unique About OpenDSS?

OpenDSS was derived from a family of power system harmonics solvers designed for analysis of distributions systems. This analysis requires very detailed models of the circuit topology. This gives the program the capability to represent nearly any circuit topology that might be encountered on a power distribution system. While the power flow solution is the most common application, the program is technically not a power flow program. The solution method and circuit modeling has more in common with harmonics and dynamics solvers.

The program was developed because users realized in 1996 that they were not getting the correct answer for distributed generation problems when using only the typical static power flow analysis used for distribution planning. OpenDSS was one of the first programs to implement an efficient quasi-static time series (QSTS) simulation for DER analysis. The capability was built into the program from the start.

It was recognized that it is not possible to anticipate everything that users will want to do in DER analysis and build a single user interface for this. This issue was addressed by building the program around a scripting interface that is user defined. Also, the COM interface was added so that users could drive the program from other software such as MATLAB and Python. This feature is popular among researchers and graduate students who want to do things not already supported in the program. Of course, EPRI uses this feature extensively in its research. A direct function call DLL interface (OpenDSSDirect.DLL) was also developed to allow this feature to be used on platforms and computer languages that do not support COM.



IEEE Test Cases

https://sourceforge.net/p/electricdss/code/HEAD/tree/trunk/Version8/Distrib/IEEETestCases/

EPRI Test Circuits
https://sourceforge.net/p/electricdss/code/HEAD/tree/trunk/Version8/Distrib/EPRITestCircuits/

Source Code

https://sourceforge.net/p/electricdss/code/HEAD/tree/trunk/Version8/Source/

Top level of Distribution area (Releases)

https://sourceforge.net/p/electricdss/code/HEAD/tree/trunk/Version8/Distrib/

Examples

https://sourceforge.net/p/electricdss/code/HEAD/tree/trunk/Version8/Distrib/Examples/

License
=======

Use of this software is subject to a license. The terms are in:

 1 - A file called "license.txt" distributed with the software,
 2 - The user manual, and
 3 - The executable program's Help/About dialog box