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Summary: This article presents an adaptive voltage sag compensation scheme by using interline bridge‐type fault current limiter (IBFCL) in radial distribution network to protect customers connected to the point of common coupling (PCC). Regarding voltage sag depth, the IBFCL provides a variable resistor in faulted feeder to compensate the PCC voltage at the acceptable level under whole voltage sag condition. To achieve this, a new control system based on the deviation of voltage sag at PCC bus is designed and implemented to the IBFCL. To check the effectiveness of the IBFCL for voltage sag compensation, extensive time domain simulations are performed under both symmetrical and asymmetrical fault conditions on the distribution system in professional's simulation tool for analyzing power systems transients (PSCAD)/electromagnetic transients including DC (EMTDC) environment. Also, its performance and control system are compared to the conventional BFCL and transformer‐type solid‐state fault current limiter (TSSFCL). The simulation results show that by using only one limiting resistor in the IBFCL used in distribution systems including multifeeders connected to the PCC, in addition to reducing the cost of limiting the fault current, the PCC bus voltage has effectively compensated the PCC bus. Also, comparison analysis with the conventional BFCL and TSSFCL shows that it outperforms them in terms of fault detection, voltage recovery time, and fault current limitation. [ABSTRACT FROM AUTHOR]

Summary: This paper proposes a new concept for limiting fault current in distribution systems with interline bridge‐type fault current limiter (IBFCL). It includes two or more BFCLs connected to only a common limiting resistor in DC link, which result in considerable cost saving. This configuration is inserted in series with feeders connected to a point common coupling (PCC). At first, the principle and characteristics of IBFCL are described. Then, a theoretical analysis of limiting performance and parameter design of the IBFCL is explained. Finally, the performance of the IBFCL for limiting fault current is validated on the distribution system comprising of parallel feeders connected to PCC through electromagnetic simulations by PSCAD/EMTDC under symmetrical and asymmetrical faults as well as different load current conditions. Simulation results show that the IBFCL provides a cost‐effective approach for limiting fault current in distribution system. [ABSTRACT FROM AUTHOR]

This paper presents the analysis of a novel framework of study and the impact of different market design criterion for the generation expansion planning (GEP) in competitive electricity market incentives, under variable uncertainties in a single year horizon. As investment incentives conventionally consist of firm contracts and capacity payments, in this study, the electricity generation investment problem is considered from a strategic generation company (GENCO) ′ s perspective, modelled as a bi-level optimization method. The first-level includes decision steps related to investment incentives to maximize the total profit in the planning horizon. The second-level includes optimization steps focusing on maximizing social welfare when the electricity market is regulated for the current horizon. In addition, variable uncertainties, on offering and investment, are modelled using set of different scenarios. The bi-level optimization problem is then converted to a single-level problem and then represented as a mixed integer linear program (MILP) after linearization. The efficiency of the proposed framework is assessed on the MAZANDARAN regional electric company (MREC) transmission network, integral to IRAN interconnected power system for both elastic and inelastic demands. Simulations show the significance of optimizing the firm contract and the capacity payment that encourages the generation investment for peak technology and improves long-term stability of electricity markets. [ABSTRACT FROM AUTHOR]

Wind energy integration into microgrids, has introduced new challenges to energy management systems because of its intermittent behaviour. Owing to continuous changes in generation and consumption, the energy price is volatile. This study proposes a new two‐stage stochastic framework for day‐ahead scheduling of microgrids. Uncertainties associated to wind power generation, real‐time electricity price and load demand are considered. Different scenarios are generated using autoregressive moving‐average method and then are reduced using fast‐forward technique. On the first stage, the microgrid master controller determines the procured energy from the day‐ahead market and commitment states of distributed energy resources (DERs). In the second stage, the purchased energy from the real‐time market and schedules of committed DERs are obtained. The problem is modelled using mixed‐integer linear programming approach and is solved via CPLEX® optimizer. Both grid‐connected and stand‐alone modes of operation are investigated. Despite of high operation cost in island mode, coordination of energy storage systems, incentive‐based and price‐based demand response (DR) programmes affect economy of microgrids. The framework is examined on a test microgrid. Results show that both of the releasing the microgrid master controller authority and DR resources result in significant saving in operating; especially in emergency conditions such as islanded mode. [ABSTRACT FROM AUTHOR]