• Journal of Electrical Engineering and Technology
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• 제13권2호
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• pp.608-619
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• 2018

As distributed generation (DG) is connected to grid, there is new node-type occurring in distribution network. An efficient algorithm is proposed in this paper to calculate power flow for weakly meshed distribution network with DGs in different load models. The algorithm respectively establishes mathematical models focusing on the wind power, photovoltaic cell, fuel cell, and gas turbine, wherein the different DGs are respectively equivalent to PQ, PI, PQ (V) and PV node-type. When dealing with PV node, the algorithm adopts reactive power compensation device to correct power, and the reactive power allocation principle is proposed to determine reactive power initial value to improve convergence of the algorithm. In addition, when dealing with the weakly meshed network, the proposed algorithm, which builds path matrix based on loop-analysis and establishes incident matrix of node voltage and injection current, possesses good convergence and strong ability to process the loops. The simulation results in IEEE33 and PG&G69 node distribution networks show that with increase of the number of loops, the algorithm's iteration times will decrease, and its convergence performance is stronger. Clearly, it can be effectively used to solve the problem of power flow calculation for weakly meshed distribution network containing different DGs.

• 전기학회논문지
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• 제66권10호
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• pp.1460-1465
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• 2017

Outage areas can be transferred to adjacent feeders to restore power supply in case of the fault on the distribution system. Feeders in the small island or mountain area may not have backup feeders due to the low density of load. In this weakly meshed open loop system, BESS can be used as a backup feeder to improve reliability of power supply. This paper proposes a new network reconfiguration method for BESS based service restoration. Fuzzy decision making technique is adopted to deal with fuzziness of service restoration planning rules. Case studies using KEPCO real distribution system have been performed to verify feasibility of the proposed method.