Electric Grid Modeling for Distribution Generation Applications
2012 M.Eng. thesis, McGill University
Written by Michael Nicholas George
Chapter 7:
Conclusions
7.2 Future Work
The work presented here can be extended in several ways, with the aims of providing suitable platforms for testing new distributed generation solutions and associated interconnection issues.
The most apparent extension of this work would be in articulating guidelines for that suitably retain some imbalance in the benchmark feeder upon reduction. This would accommodate the needs for more specialized protection coordination analysis, drawing better focus on the actual characteristics of the protective devices themselves.
This methodology can be further demonstrated and verified by applying it on a great variety of rural distribution feeders. In addition to validating upon individual feeders, this work can be expanded to include application on multiple feeders that share the same substation or on neighboring feeders with switchable interconnections between them. DG islanding issues sometimes involve interactions between multiple feeders with a shared substation, giving potential importance to this direction of work.
7.1 Summary
Distributed generation resources are proliferating and comprise an increasing share of the electric power system’s generating capability. This holds great promise for alleviating transmission constraints, curtailing environmentally harmful emissions, and providing effective demand-side management capability. This thesis described the procedure to obtain a distribution feeder model compatible for use with currently standing DG interconnection guidelines.
The benchmarking methodology is used to obtain a balanced three-phase distribution feeder model, given an unbalanced distribution feeder model comprising a large number of laterals and unbalanced spot loads.
The need for a balanced feeder model arose from the necessity for the ability to connect a DG source at any point along the feeder in order to perform impact studies, particularly those concerning DG islanding and related feeder protection issues.
The necessary analytical steps were described in detail, and a literature review was performed to summarize the available distribution feeder reduction techniques. This circuit simplification methodology would be used to serve the needs of typical system studies. Furthermore, criteria were set on assessing the quality of the resulting feeder reduction, based on voltage profiles and losses. The proposed reduction methodology serves a range of impact studies comprising typical power flow and voltage drop analyses, fault analysis, and classical electromechnical-type transient analysis that are pertinent in the simulation of islanding events.
The proposed reduction methodology was validated against commercial-grade distribution analysis packages and an electromagnetic transients program. The results were found to be in satisfactory agreement.