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38
The impact of plugin hybrid electric vehicles on distribution networks: a review and outlook, “Renewable and Sustainable Energy Reviews
, 2011
"... This paper analyzes the potential impacts of plugin hybrid electric vehicles (PHEVs) on locational marginal prices (LMPs). PHEVs are the next generation of hybrid electric vehicles with batteries that can be recharged by plugging into a standard electric power outlet. On the one hand, PHEVs produce ..."
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This paper analyzes the potential impacts of plugin hybrid electric vehicles (PHEVs) on locational marginal prices (LMPs). PHEVs are the next generation of hybrid electric vehicles with batteries that can be recharged by plugging into a standard electric power outlet. On the one hand, PHEVs produce less emission, have higher mileage, and reduce dependency on foreign supply of oil. On the other hand, economical and technical obstacles still exist, and the potential impacts on both transportation and electric power systems need to be studied. Earlier studies have examined the potential impacts on nonLMPbased electricity markets. This paper analyzes how wholesale electricity prices in LMPbased electricity markets would be affected by PHEV penetration. Simulation results from a PJM fivebus test example show that, if the electricity load increases by 20 % due to recharging PHEVs, the loadweighted mean and standard deviation of LMPs would increase by more than 70 % and 140%, respectively. The effects of battery stations that provide hotswap service are also studied. If the load increases by 20%, by taking advantage of the spatial price differences and shipping batteries between different locations, the battery stations could recharge the batteries at 63 % of what it would cost for PHEV drivers to recharge in home garages. At the same time, the mean of LMPs would only increase by about 22 % and the standard deviation would even decrease. 1
Stateoftheart, challenges, and future trends in security constrained optimal power flow
 ELECTRIC POWER SYSTEMS RESEARCH
, 2011
"... This paper addresses the main challenges to the security constrained optimal power flow (SCOPF) computations. We first discuss the issues related to the SCOPF problem formulation such as the use of a limited number of corrective actions in the postcontingency states and the modeling of voltage an ..."
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Cited by 19 (2 self)
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This paper addresses the main challenges to the security constrained optimal power flow (SCOPF) computations. We first discuss the issues related to the SCOPF problem formulation such as the use of a limited number of corrective actions in the postcontingency states and the modeling of voltage and transient stability constraints. Then we deal with the challenges to the techniques for solving the SCOPF, focusing mainly on: approaches to reduce the size of the problem by either efficiently identifying the binding contingencies and including only these contingencies in the SCOPF or by using approximate models for the postcontingency states, and the handling of discrete variables. We finally address the current trend of extending the SCOPF formulation to take into account the increasing levels of uncertainty in the operation planning. For each such topic we provide a review of the state of the art, we identify the advances that are needed, and we indicate ways to bridge the gap between the current state of the art and these needs.
A LinearProgramming Approximation of AC Power Flows
, 2013
"... Linear activepoweronly DC power flow approximations are pervasive in the planning and control of power systems. However, these approximations fail to capture reactive power and voltage magnitudes, both of which are necessary in many applications to ensure voltage stability and AC power flow feasib ..."
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Cited by 17 (4 self)
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Linear activepoweronly DC power flow approximations are pervasive in the planning and control of power systems. However, these approximations fail to capture reactive power and voltage magnitudes, both of which are necessary in many applications to ensure voltage stability and AC power flow feasibility. This paper proposes linearprogramming models (the LPAC models) that incorporate reactive power and voltage magnitudes in a linear power flow approximation. The LPAC models are built on a convex approximation of the cosine terms in the AC equations, as well as Taylor approximations of the remaining nonlinear terms. Experimental comparisons with AC solutions on a variety of standard IEEE and MATPOWER benchmarks show that the LPAC models produce accurate values for active and reactive power, phase angles, and voltage magnitudes. The potential benefits of the LPAC models are illustrated on two “proofofconcept” studies in power restoration and capacitor placement.
An AgentBased Computational Laboratory for Testing the Economic Reliability of Wholesale Power Market Designs
 Market Designs, Proceedings
, 2005
"... Commission proposed the Wholesale Power Market Platform (WPMP) for adoption by all U.S. wholesale power markets. The WPMP market design envisions dayahead, realtime, and ancillary service markets maintained and operated by an independent system operator or regional transmission organization. Previ ..."
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Commission proposed the Wholesale Power Market Platform (WPMP) for adoption by all U.S. wholesale power markets. The WPMP market design envisions dayahead, realtime, and ancillary service markets maintained and operated by an independent system operator or regional transmission organization. Previous work reports on the development of an agentbased model for testing the economic reliability of the WPMP market design. This paper reports on the implementation of this model as an agentbased computational laboratory. Initial experiments focusing on optimal power flow solution methods for the dayahead and realtime markets are also discussed. I.
Convex Relaxation of Optimal Power Flow  Part I: Formulations and Equivalence
, 2014
"... This tutorial summarizes recent advances in the convex relaxation of the optimal power flow (OPF) problem, focusing on structural properties rather than algorithms. Part I presents two power flow models, formulates OPF and their relaxations in each model, and proves equivalence relations among them. ..."
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This tutorial summarizes recent advances in the convex relaxation of the optimal power flow (OPF) problem, focusing on structural properties rather than algorithms. Part I presents two power flow models, formulates OPF and their relaxations in each model, and proves equivalence relations among them. Part II presents sufficient conditions under which the convex relaxations are exact.
Approximating Line Losses and Apparent Power in AC Power Flow Linearizations
 PROCEEDINGS OF THE 2012 IEEE POWER & ENERGY SOCIETY GENERAL MEETINGS (PES 2012
, 2012
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A local control approach to voltage regulation in distribution networks
 in Proc. North American Power Symposium
, 2013
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Nodal Pricing in the German Electricity Sector – A Welfare Economics Analysis, with Particular Reference to Implementing Offshore Wind Capacities Authors:
"... This paper compares the results of different pricing systems in the German electricity sector. In particular, we compare a competitive nodal pricing approach to a cost minimization scenario under a uniform price. The model also simulates the effects of increasing offshore wind energy in the North Se ..."
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This paper compares the results of different pricing systems in the German electricity sector. In particular, we compare a competitive nodal pricing approach to a cost minimization scenario under a uniform price. The model also simulates the effects of increasing offshore wind energy in the North Sea, from the current 0 GW to 8 and 13 GW, respectively. Our model of the German electricity system includes 425 lines and 310 nodes of the 380kV and the 220kV grid. Power flows are calculated based on the DC Load Flow Model using a slightly modified version of the traditional approach (Schweppe et al., 1988, Stigler and Todem, 2005). Demand is proxied by linear demand functions that are regionally differentiated. Our results show that the nodal pricing regime is more efficient than uniform pricing and that offshore wind input leads to a significant welfare gain. The model also indicates that 8 GW offshore wind would be accommodated by the current network without significant investments.
Locational Marginal Pricing Basics for Restructured Wholesale Power Markets
"... Although Locational Marginal Pricing (LMP) plays an important role in many restructured wholesale power markets, the detailed derivation of LMPs as actually used in industry practice is not readily available. This lack of transparency greatly hinders the efforts of researchers to evaluate the perfor ..."
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Although Locational Marginal Pricing (LMP) plays an important role in many restructured wholesale power markets, the detailed derivation of LMPs as actually used in industry practice is not readily available. This lack of transparency greatly hinders the efforts of researchers to evaluate the performance of these markets. In this paper, different AC and DC optimal power flow (OPF) models are presented to help understand the derivation of LMPs. As a byproduct of this analysis, the paper provides a rigorous explanation of the basic LMP and LMPdecomposition formulas (neglecting real power losses) presented without derivation in the business practice manuals of the U.S. Midwest Independent System Operator (MISO).