Service restoration method considering simultaneous disconnection of distributed generators by one‐bank fault of distribution system

Abstract

SUMMARYDistributed generators (DGs) such as fuel cells and solar cells are going to be installed in the demand side of distribution systems. The DGs can reduce distribution loss by appropriate allocation. However, there are several problems installing DGs such as service restoration of distribution system with DGs and so on. When one bank fault of distribution substation occurs in distribution system, since DGs are simultaneously disconnected from the system, it is not easy to restore isolated load by one bank switching in distribution substation. Therefore, a service restoration method to determine restoration configuration and restoration procedures (switching procedure from normal configuration to restoration configuration) taking into account simultaneous disconnection of DGs is needed. In this paper, the authors propose a computation method to determine the optimal restoration configuration and the restoration procedure considering simultaneous disconnection of DGs by one bank fault of distribution system. In the proposed algorithm, after all of the restoration configuration candidates are effectively enumerated under the operational constraints, the optimal configuration to restore the isolated load is selected among enumerated configuration candidates. After determining the optimal restoration configuration, the optimal restoration procedures are obtained by greedy algorithm. Numerical simulations are carried out for a real scale system model with 237 sectionalizing switches (configuration candidates are 2 237 ) and 21 DGs (total output is 5250 kW which is 3% of total load) in order to examine the validity of the proposed algorithm.

Service Restoring Reconfiguration for Distribution Networks Considering Uncertainty in Available Information

“…The authors have proposed an enumeration-based solution method for the distribution network reconfiguration [23,25,36]. In these methods, first, the target distribution network is partitioned into several groups.…”

“…The top priority in the emergency condition is to immediately resume service to as many outage consumers as possible [2][3][4][5][6][7]12,15,[23][24][25]. Therefore, the service restoration problem is formulated as an optimization problem in terms of minimizing the weighted sum of the total amount of outage loads and the number of switching operations.…”

“…Moreover, PVs connected to the outage load sections must be normally isolated from the distribution network to prevent their islanding operations [20,21]. Most of the traditional service restoration problems require accurate information of the load sections, including the status of the PVs, while the PV installation is accompanied by additional uncertainty in the measurement and estimation of the section loads [22][23][24][25]. That is, we cannot remove the uncertainty-originated operational risks of the overload and the voltage limit violation in the determined "optimal" restoration configuration.…”

Service Restoration Problem in Distribution Power System using Improved GA

“…Considerable research has been done for the purpose of creating switching procedures, prioritizing areas, and minimizing the restoration load and power loss [1][2][3][4]. Considerable research has been done for the purpose of creating switching procedures, prioritizing areas, and minimizing the restoration load and power loss [1][2][3][4].…”

“…With respect to creating a target system for restoration, a variety of methods have been proposed [2,4] for cases in which the areas without power can all be restored (normal bank capacity ≥ load capacity). However, with respect to the problem of minimization of the restoration load in the remaining cases (normal bank capacity < load capacity) in which only some areas are without power, there are few reports.…”