GridLAB-D and OpenDSS: Better Together 5 September 2019 About the Image: PNNL Aerial Photo Aerial photo of the Pacific Northwest National Laboratory campus from the west. https://www.flickr.com/photos/pnnl/42712951642/in/album-72157670058514908/ Thomas E. McDermott Thomas.McDermott@pnnl.gov

GridLAB-D originated to handle buildings, controls, grid and markets. OpenDSS Domains Thomas.McDermott@pnnl.gov September 5, 2019

OpenDSS originated from harmonics analysis and DER siting optimization. Auto-adding DG at yellow sites to defer feeder and substation upgrades Injecting harmonic currents into a grid model Thomas.McDermott@pnnl.gov September 5, 2019

OpenDSS solves time-series power flow with two loops; power flow (fixed point) and controls (queue). Note: phases are numbered and flexibly connected Thomas.McDermott@pnnl.gov September 5, 2019

Which one is better? It depends… GridLAB-D OpenDSS Main Developers PNNL, SLAC EPRI, PNNL Programming Language C/C++ Delphi/Free Pascal Total Downloads to 9/2/2019 89,362 88,086 Strong Suit Cross-domain, multi-agent Fast and robust power flow Unique Features Weather Harmonics Building Thermal Models Protection Microgrid with Frequency Flexible Phasing Rotating Machines Any Transformer Connection Thermostats and Schedules Ease of Parallel Processing Time Stepping Variable Fixed (w/ pause and change) Automation HTTP, FNCS, HELICS Windows COM, FNCS Platforms Linux, Windows, Mac Windows (GUI), Linux, Mac Thomas.McDermott@pnnl.gov September 5, 2019

Example 1: feeder model conversions between CYMDIST, OpenDSS, CIM and GridLAB-D An SCE circuit layout in OpenDSS Thomas.McDermott@pnnl.gov September 5, 2019

Example 2: automates OpenDSS via Framework for Network Cosimulation (FNCS), as with GridLAB-D Total Feeder Load with Switching and PV Add 285 kW PV Open At Noon opendsscmd fncs_broker fncs_player Thomas.McDermott@pnnl.gov September 5, 2019

Example 3: linking OpenDSS power flow to GridLAB-D houses and weather over FNCS irradiance power voltage Thomas.McDermott@pnnl.gov September 5, 2019

References Downloading GridLAB-D: https://sourceforge.net/projects/gridlab-d/ Downloading OpenDSS: https://sourceforge.net/projects/electricdss/ Downloading OpenDSSCmd: https://sourceforge.net/projects/electricdss/files/OpenDSSCmd/ Chassin, Fuller, Djilali, “GridLAB-D: An agent-based simulation framework for smart grids”, 2014, doi: 10.1155/2014/492320 Dugan, McDermott, “An open source platform for collaborating on smart grid research”. 2011, doi: 10.1109/PES.2011.6039829 Ciraci, Daily, Fuller, Fisher, Marinovici, Agarwal, “FNCS: a framework for power system and communication networks co-simulation”, 2014, https://dl.acm.org/citation.cfm?id=2665044 Model Converters: https://github.com/GRIDAPPSD/Powergrid-Models/tree/develop CIM Schema: https://gridappsd.readthedocs.io/en/master/developer_resources/ index.html#cim-documentation Thomas.McDermott@pnnl.gov September 5, 2019