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access icon free Three-phase power flow calculations by direct Z LOOP method for microgrids with electric vehicle charging demands

© The Institution of Engineering and Technology
Received 19/09/2012, Accepted 10/03/2013, Revised 04/02/2013, Published

A three-phase power flow solution approach for microgrids with electric vehicle (EV) demands is proposed in this study. Based on the loop frame of reference, a direct iterative approach is adopted. Most of microgrids are essentially unbalanced; hence, the proposed approach is developed based on true phase (a-b-c) frame, rather than the sequence-component frame. Based on the true phase frame, the total dimension of the performance equations of the network is the minimum required to represent the microgrid system. The mathematical component models, such as feeders, capacitors/reactors, transformers, automatic voltage regulators, loads, distributed energy resource units and EV demands can easily be involved in the proposed approach. To examine the validity of the proposed algorithm, four IEEE sample systems and a practical Taiwan Power Company distribution system are used as benchmarks for comparisons. The test results show that the proposed approach is accurate, efficient and robust with minimum memory requirements for three-phase power flow studies.

Inspec keywords: battery powered vehicles; load flow; iterative methods; power distribution; distributed power generation

Other keywords: microgrid system; true phase frame; capacitors-reactors; EV charging demands; loop frame; electric vehicle charging demands; practical Taiwan Power Company distribution system; direct iterative approach; direct ZLOOP method; distributed energy resource units; transformers; EV demands; feeders; mathematical component models; three-phase power flow calculations; IEEE benchmark systems; sequence-component frame; automatic voltage regulators

Subjects: Interpolation and function approximation (numerical analysis); Distribution networks; Transportation; Distributed power generation

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