Energy Management
Sh. Shadi; J. Salehi; A. Safari
Abstract
Energy management (EM) in smart distribution networks (SDN) is to schedule the power transaction between the SDN and the existing distributed energy resources (DERs) e.g., distributed generations, especially renewable resources and electrical vehicles, from an eco-technical viewpoint. Due to the dual ...
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Energy management (EM) in smart distribution networks (SDN) is to schedule the power transaction between the SDN and the existing distributed energy resources (DERs) e.g., distributed generations, especially renewable resources and electrical vehicles, from an eco-technical viewpoint. Due to the dual role of electric vehicles (EVs) acting as a power source and load, they presented both challenges and opportunities in EM. The complexity of EM increases as DERs become more prevalent in SDN. Moreover, the uncertainties of renewable resources, price, and load besides the uncertainties related to the place, amount, and time of EV’s charging makes EM a more intricate field. This supports the necessity of extensive tools and approaches to manage EM in SDNs. In this respect, this paper proposes an optimum scenario-based stochastic energy management scheme for intelligent distribution networks. The proposed approach is modeled as a MINLP problem and solved in GAMS software under the DICOPT solver. The test is conducted on a 33-bus SDN with and without factoring in uncertainties.
M. Faghihi Rezaei; M. Gandomkar; J. Nikoukar
Abstract
Installing the renewable energy sources (RESs) in distribution networks changes the fault current direction, increases the fault current level and, consequently, eliminates the protection coordination between the protective devices. Overcurrent relays are among the most important protective devices in ...
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Installing the renewable energy sources (RESs) in distribution networks changes the fault current direction, increases the fault current level and, consequently, eliminates the protection coordination between the protective devices. Overcurrent relays are among the most important protective devices in distribution networks. Proper performance of the protective system requires protection coordination between the overcurrent relays. The present paper proposes a new protection coordination scheme using digital directional overcurrent relays (DOCRs) and dual-setting digital overcurrent relays (DS-DOCRs) in the distribution network in the presence of the RESs and energy storage systems (ESSs). For this purpose, a multi-stage objective function was used. In the first stage, a weighted objective function was employed to optimize the size and location of the RESs as well as the location and impedance of the FCLs in order to reduce the loss, improve the voltage profile and decrease the variation of the feeders' currents at the connection time of the RESs. In the second stage, DOCR and DS-DOCR settings optimization, which included parameters A and B in addition to parameters I${}_{p}$ and TDS, was used to restore the lost protection coordination for the fault current in the shortest possible time. The simulation results on the IEEE 33-bus network in the presence of RESs using genetic algorithm and PSO algorithm method as well as DPL programming language in DIgSILENT software showed that the total operating time of digital relays and network loss were reduced and voltage profile was significantly improved.
M. Shadnam Zarbil; A. Vahedi
Abstract
Due to the presence of power electronic converters in electric vehicle battery chargers, the electrical power drawn from the distribution system has severe distortions which pose many problems to the power quality. Herein, the impact of chargers in terms of indicators, e.g., penetration level, battery ...
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Due to the presence of power electronic converters in electric vehicle battery chargers, the electrical power drawn from the distribution system has severe distortions which pose many problems to the power quality. Herein, the impact of chargers in terms of indicators, e.g., penetration level, battery state of charge, type of charging stations, the time of connection of chargers to the network, and the location of charging stations was comprehensively studied on a sample distribution network. The effect of these chargers was investigated based on power quality parameters, e.g., total harmonic distortion (THD) and voltage profile, and the effect of each indicator on these parameters was determined. To minimize the effects of the chargers, an IEEE 33-bus distribution sample network was optimized with the objective functions of voltage drop and THD. Based on this optimization algorithm, the installation placement and the power capacity of the charging stations were obtained to achieve the lowest voltage drop and THD.
Distribution Systems
S. Ghaemi; K. Zare
Abstract
The determination of practical and coherent policy to pin down the price in restructured distribution networks should be considered as a momentous topic. The present paper introduces a new method of distribution marginal price (DMP) calculation. The main aim of this paper is to evaluate the DMP for both ...
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The determination of practical and coherent policy to pin down the price in restructured distribution networks should be considered as a momentous topic. The present paper introduces a new method of distribution marginal price (DMP) calculation. The main aim of this paper is to evaluate the DMP for both producers and consumers separately. For this purpose, the first part of the procedure emphasizes a price by which the producers should sell their power. To meet this target, the share of each node plays a significant role in the total active loss of the network. The producers will make a substantial profit when their efficiency leads to decreasing the share of the node that is associated with the total loss. In the second part of the procedure, DMP is computed for the consumers. In this part, based on the distribution system operator’s decision about the obtained profit allocated to the consumers, their payment has been reduced. This method has been applied to the 33-Bus Distribution System. The results demonstrate the characteristic of the method which tends to encourage the distributed units to increase their output powers. This is the reason why the penetration of these units in the networks is an opportunity for consumers from an economic aspect in such a way that merchandising surplus (MS) becomes zero.
