...It incorporates advanced modeling techniques with high-performance algorithms to deliver the latest in end-use load modeling technology integrated with three-phase unbalanced power flow, and retail market systems. Historically, the inability to effectively model and evaluate smart grid technologies has been a barrier to adoption; GridLAB-D is designed to address this problem.
User documentation can be found at: http://gridlab-d.shoutwiki.com/wiki/Quick_links
The source code is available from GitHub. See https://github.com/gridlab-d/gridlab-d.
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