v2.3.0

Release with major improvements on Feb. 1 2026.

Add new device static var source SV_SOURCE and multi-terminal HVDC MT_HVDC, and basic dynamic models.
Add new dynamic models of WT_GENERATOR, PV_UNIT, and ES_STORAGE, including both grid-following and grid-forming models.
Add new function of short-circuit solver.
Support seperate solution of P and Q equations in decoupled PQ powerflow solution for tuning powerflow.
Add nominal Qmax and Qmin for sources.
Add new support of load voltage sensor and lcc_hvdc2t model degrading in dynamic simulation for better convergence.
Reorganize interfaces for building meters.
Optimize codes for higher powerflow and dynamic simulation performance.
Add CMakeFiles.txt for compilation with CMake.
stepspy is also updated.

Two built stepspy can be found as follows:

stepspy.tar.gz: stepspy module with libSTEPS.so built on Ubuntu 24.04.2 LTS
stepspy.zip: stepspy module with libSTEPS.dll built on Windows 11.

STEPS v2.0.0

Great News on Oct. 16, 2023.
In v2.0.0, STEPS for the very first time fully supports the THREE major functions of power system analysis: powerflow solution, short circuit analysis, and dynamic simulation. See details in commit [5fccff9].
Here is a Windows version of stepspy with 'libSTEPS.dll'. Just download, unpack, and enjoy.
If you want to try Linux version, follow instructions below or contact maintainer.
-- How to build STEPS kernel: https://github.com/changgang/steps/wiki/How-to-build-STEPS-kernel
-- How to install stepspy module to Python: https://github.com/changgang/steps/wiki/How-to-install-stepspy-in-Python

V1.4

Default GENCLS model will be automatically added to generators without sync generator model when checking missing models. If the function to check missing models is not called, the default GENCLS model will not be added.
The check functions of some dynamic models are finished. It is useful for checking improper parameters.
Update stepspy with some new APIs to get spinning reserver.

V1.3.1

Minor changes to V1.3.
1, fix bug in IEEEG1 when T1 or T2 is non-zero
2, stepspy is updated with new APIs to enable or disable specific model of generator. default string encoding is changed to GB18030.

v1.3

Fix bug in building Z matrix. Add new APIs api_clear_meters, api_get_system_angular_stable_flag. Update implementation of bus frequency calculation. Reconstructure folder architecture and modify some benchmarks.
Update stepspy to add APIs is_system_angular_stable, get_(lines/transformers/hvdcs)between_lines(), set(generator/wt_generator/pv_unit/energy_storage/load/hvdc)_power(). Helps to stepspy module are added.
This version is compatible with -std=c++14 flag and can be complied with gcc>=4.9.2.
The attached libSTEPS.dll is for 64-bit Python 3 on Windows platform.

v1.1

This is a minor version of STEPS with significant performance improvement. APIs are backward compatible.
Binary libSTEPS.dll is provided for 64bit Python on x64-based Windows system.