TY - JOUR
T1 - Optimal Topology Control With Physical Power Flow Constraints and N-1 Contingency Criterion
JF - IEEE Transactions on Power Systems
Y1 - 2015/01//
SP - 1
EP - 9
A1 - Poyrazoglu, Gokturk
A1 - HyungSeon Oh
KW - CERTS
KW - locational marginal pricing
KW - optimal power flow (OPF)
KW - reliability and markets
KW - RM13-003
AB - In this paper, a novel solution method is proposed for the optimal topology control problem in AC framework with N-1 reliability. The resultant new topology of the proposed method is guaranteed to yield a better objective function value than the global solution of the problem with the original topology. In order to prove our statement, semi-definite programming relaxation is formulated to find a lower bound to the objective function value of the problem. The proposed method is favorable for parallelization to increase the computational efficiency, and the parallel computing flowchart is presented. Computational time of the algorithm for IEEE test cases is reported. An in-house power market simulator is developed to simulate a market environment complete with optimal topology control mechanism. Simulations held by participating human subjects are analyzed under the subtitles of the total operating cost, real power losses, and locational marginal price (LMP) variance. A simple example is illustrated to show that the resultant network topology may increase the real power losses while still providing a lower operating system cost than that of the original topology.
JO - IEEE Trans. Power Syst.
DO - 10.1109/TPWRS.2014.2379112
ER -
TY - JOUR
T1 - Is Deferrable Demand an Effective Alternative to Upgrading Transmission Capacity?
JF - Journal of Energy Engineering
Y1 - 2014/03//
SP - B4014005
A1 - Alberto J Lamadrid
A1 - Timothy D. Mount
A1 - Wooyoung Jeon
A1 - Hao Lu
KW - electricity markets
KW - energy storage
KW - optimal power flow (OPF)
KW - reliability and markets
KW - RM12-004
AB - With high penetrations of variable generation from wind turbines in remote locations, transmission capacity may be inadequate to transfer this relatively inexpensive source of generation to demand centers. The major reason is that transmission corridors into load centers are often congested when the system load is high, and additional wind generation is effectively shut out. In contrast, when the system load is low and the wind is blowing, wind generation may be able to meet most of the load throughout the network subject to the specific limitations of the network’s topology. This paper compares the system costs of two very different ways of reducing congestion on the network to increase the annual amount of potential wind capacity dispatched. The first way uses the standard supply side solution of upgrading transmission capacity on the network. The second way uses a demand-side approach in which deferrable demand shifts the system load from on-peak periods to off-peak periods. In addition, the deferrable demand can be used to offset the inherent variability of wind generation and reduce the amount of reserve generating capacity needed to maintain operating reliability. In fact, reducing the total amount of conventional generating capacity needed to maintain system adequacy for a given amount of installed wind capacity is a major source of cost savings with deferrable demand. The simulation is based on a multiperiod (24 h), stochastic, security constrained optimal power flow (SCOPF) and a reduction of the Northeastern Power Coordinating Council (NPCC) network. This framework includes stochastic forecasts of potential wind generation at multiple sites as inputs as well as deferrable demand (e.g., thermal storage) at different load centers. It determines the optimum patterns of dispatch, reserves, and ramping to maintain reliability over a set of credible contingencies. The results demonstrate that deferrable demand can effectively (1) lower the average wholesale prices for energy;, (2) reduce the installed generating capacity needed to maintain system adequacy; and (3) mitigate the ramping costs associated with wind variability. With a sufficient amount of deferrable demand, the typical daily pattern of load can be flattened, and all the variability of wind generation can be mitigated. The overall conclusion is that deferrable demand reduces the total annual cost of the conventional system substantially more than upgrading transmission capacity, and it is an effective alternative to the standard supply side solution.
VL - 141
IS - 1
JO - J. Energy Eng.
DO - 10.1061/(ASCE)EY.1943-7897.0000182
ER -
TY - CONF
T1 - An optimization based generator placement strategy in network reduction
T2 - 2014 North American Power Symposium (NAPS)
Y1 - 2014/09//
SP - 1
EP - 6
A1 - Zhu, Yujia
A1 - Daniel J. Tylavsky
KW - CERTS
KW - network reduction
KW - optimal power flow (OPF)
KW - reliability and markets
KW - RM11-005
AB - Solving the optimal power flow (OPF) problem on a large power system is computationally expensive. Network reduction and ac-to-dc network conversion can relieve this burden by simplifying the full system model to a smaller and mathematically simpler model. Traditional reduction methods, like Ward reduction, fractionalize generators when the buses they are attached to are removed, and scatters these fractions to topologically adjacent buses. In some OPF applications, this type of generator modeling is problematic. An improved approach is to keep generators intact by moving them whole to buses in reduced model and then redistributing loads to maintain base-case line flows. Determining generator placement using a traditional shortest electrical distance (SED) based method may result in cases where the OPF solution on reduced model is infeasible while the full model has a feasible solution. In this paper, an improved generator placement method is proposed. Tests show that the proposed method yields a better approximation to the full model OPF solutions and is more likely to produce a reduced model with a feasible solution if the unreduced model has a feasible solution.
JF - 2014 North American Power Symposium (NAPS)
PB - IEEE
CY - Pullman, WA, USA
DO - 10.1109/NAPS.2014.6965401
ER -
TY - CONF
T1 - Transient stability constrained optimal power flow for cascading outages
T2 - 2014 IEEE Power & Energy Society General Meeting
Y1 - 2014/07//
SP - 1
EP - 5
A1 - Lei Tang
A1 - James D. McCalley
KW - AA09-001
KW - optimal power flow (OPF)
KW - RTGRM
KW - System Security Tools
AB - This paper presents a strategy to implement transient stability constrained optimal power flow in cascading outages. Anticipatory computing detects transient instability due to weakened system conditions in cascading progressions and prepares transient stability constraints for optimal power flow. The prepared constraints use trajectory sensitivities, which can speed up the analysis by estimating rotor angle response changing with generation levels. The proposed strategy has been tested on a 140-bus, 48-machine system.
JF - 2014 IEEE Power & Energy Society General Meeting
PB - IEEE
CY - National Harbor, MD, USA
DO - 10.1109/PESGM.2014.6939917
ER -
TY - JOUR
T1 - Implementation of a Large-Scale Optimal Power Flow Solver Based on Semidefinite Programming
JF - IEEE Transactions on Power Systems
Y1 - 2013/
SP - 3987
EP - 3998
A1 - Molzahn, Daniel K.
A1 - Holzer, Jesse T.
A1 - Bernard C. Lesieutre
A1 - Christopher L. DeMarco
KW - AA13-005
KW - AARD
KW - optimal power flow (OPF)
KW - RTGRM
AB - The application of semidefinite programming to the optimal power flow (OPF) problem has recently attracted significant research interest. This paper provides advances in modeling and computation required for solving the OPF problem for large-scale, general power system models. Specifically, a semidefinite programming relaxation of the OPF problem is presented that incorporates multiple generators at the same bus and parallel lines. Recent research in matrix completion techniques that decompose a single large matrix constrained to be positive semidefinite into many smaller matrices has made solution of OPF problems using semidefinite programming computationally tractable for large system models. We provide three advances to existing decomposition techniques: a matrix combination algorithm that further decreases solver time, a modification to an existing decomposition technique that extends its applicability to general power system networks, and a method for obtaining the optimal voltage profile from the solution to a decomposed semidefinite program.
VL - 28
IS - 4
JO - IEEE Trans. Power Syst.
DO - 10.1109/TPWRS.2013.2258044
ER -
TY - CONF
T1 - An efficient transient stability constrained optimal power flow using trajectory sensitivity
T2 - 2012 North American Power Symposium (NAPS)
Y1 - 2012/09//
SP - 1
EP - 6
A1 - Lei Tang
A1 - James D. McCalley
KW - AA09-001
KW - optimal power flow (OPF)
KW - RTGRM
KW - System Security Tools
AB - A well-structured two-step efficient transient stability constrained optimal power flow is proposed. The transient stability constraints are obtained through time domain simulation and its corresponding trajectory sensitivity calculation. The process to obtain the constraints is an independent step from the dispatch problem solving. The added transient stability constraints prevent first swing instability, and bring much less computational burden than steady state security constraints. The proposed method was tested on a 9-bus system and the New England 39-bus system.
JF - 2012 North American Power Symposium (NAPS)
PB - IEEE
CY - Champaign, IL, USA
SN - 978-1-4673-2306-2
DO - 10.1109/NAPS.2012.6336308
ER -
TY - JOUR
T1 - Long-term benefits of online risk-based direct-current optimal power flow
JF - Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability
Y1 - 2012/02//
SP - 65
EP - 74
A1 - Dai, R.-C.
A1 - Pham, H.
A1 - Wang, Y.
A1 - James D. McCalley
KW - AA09-001
KW - AARD
KW - CERTS
KW - optimal power flow (OPF)
KW - RTGRM
KW - System Security Tools
AB - An online operational risk management method is presented in this paper. In this method, a risk-based direct-current (DC) optimal power flow approach is utilized to replace a traditional security-constrained DC optimal power flow approach. This risk management method is integrated into a commercial energy management system/dispatcher training simulator system to monitor and control system operation risk online. Comparison of the approach with traditional security assessment shows significant benefits over the long term via cost reduction and risk mitigation. A case study provides supporting evidence of risk mitigation in terms of steady-state angular separation reduction and cascading prevention.
VL - 226
IS - 1
JO - Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability
DO - 10.1177/1748006X11433660
ER -
TY - CONF
T1 - Optimal generation investment planning: Pt. 1: network equivalents
T2 - 2012 North American Power Symposium (NAPS)
Y1 - 2012/09//
SP - 1
EP - 6
A1 - Di Shi
A1 - Daniel L. Shawhan
A1 - Li, Nan
A1 - Daniel J. Tylavsky
A1 - John T. Taber
A1 - Ray D. Zimmerman
A1 - William D. Schulze
KW - CERTS
KW - Eastern Interconnection
KW - investment planning
KW - optimal power flow (OPF)
KW - Power system modeling
KW - reliability and markets
KW - RM11-005
AB - The requirements of a network equivalent to be used in new planning tools are very different from those used in traditional equivalencing procedures. For example, in the classical Ward equivalent, each generator in the external system is broken up into fractions. For newer long-term investment applications that take into account such things as greenhouse gas (GHG) regulations and generator availability, it is computationally impractical to model fractions of generators located at many buses. To overcome this limitation, a modified- Ward equivalencing scheme is proposed in this paper. The proposed scheme is applied to the entire Eastern Interconnection (EI) to obtain several backbone equivalents and these equivalents are tested for accuracy under a range of operating conditions. In a companion paper, the application of an equivalent developed by this procedure is used to perform optimal generation investment planning.
JF - 2012 North American Power Symposium (NAPS)
PB - IEEE
CY - Champaign, IL, USA
SN - 978-1-4673-2306-2
DO - 10.1109/NAPS.2012.6336375
ER -
TY - JOUR
T1 - MATPOWER: Steady-State Operations, Planning, and Analysis Tools for Power Systems Research and Education
JF - IEEE Transactions on Power Systems
Y1 - 2011/02//
SP - 12
EP - 19
A1 - Ray D. Zimmerman
A1 - Carlos E. Murillo-Sanchez
A1 - Robert J. Thomas
KW - CERTS
KW - load flow
KW - optimal power flow (OPF)
KW - power system economics
KW - reliability and markets
KW - RM07-002
AB - MATPOWER is an open-source Matlab-based power system simulation package that provides a high-level set of power flow, optimal power flow (OPF), and other tools targeted toward researchers, educators, and students. The OPF architecture is designed to be extensible, making it easy to add user-defined variables, costs, and constraints to the standard OPF problem. This paper presents the details of the network modeling and problem formulations used by MATPOWER, including its extensible OPF architecture. This structure is used internally to implement several extensions to the standard OPF problem, including piece-wise linear cost functions, dispatchable loads, generator capability curves, and branch angle difference limits. Simulation results are presented for a number of test cases comparing the performance of several available OPF solvers and demonstrating MATPOWER's ability to solve large-scale AC and DC OPF problems.
VL - 26
IS - 1
JO - IEEE Trans. Power Syst.
DO - 10.1109/TPWRS.2010.2051168
ER -
TY - JOUR
T1 - A Sensitivity Approach to Detection of Local Market Power Potential
JF - IEEE Transactions on Power Systems
Y1 - 2011/11//
SP - 1980
EP - 1988
A1 - Bernard C. Lesieutre
A1 - Katherine M Rogers
A1 - Thomas J. Overbye
A1 - Alex R. Borden
KW - electricity markets
KW - load flow
KW - optimal power flow (OPF)
KW - RM05-002
AB - Market power gives certain market participants the ability to manipulate the market to their advantage when their product is not substitutable by competitors. Identification of generators which have the potential for market power either individually or within a small group is performed using sensitivity information from the linear programming optimal power flow (LP OPF). The impact of network constraints on admissible price perturbations are used to group generators that have the potential to exhibit local market power. Specific price perturbation vectors are found that highlight a constraint-induced locational advantage for these suppliers. In practice, this is most commonly observed in “load pockets,” for which ISO policies mitigate market power.
VL - 26
IS - 4
JO - IEEE Trans. Power Syst.
DO - 10.1109/TPWRS.2011.2105893
ER -
TY - CONF
T1 - Dynamic optimization for the management of stochastic generation and storage
T2 - 2010 IEEE/PES Transmission and Distribution Conference and Exposition: Latin America (T&D-LA)
Y1 - 2010/11//
SP - 860
EP - 866
A1 - Alberto J Lamadrid
A1 - Timothy D. Mount
A1 - Shoemaker, Christine
KW - energy storage
KW - optimal power flow (OPF)
KW - reliability and markets
KW - renewables
KW - RM12-004
AB - In order to increase the amounts of renewable energy accommodated in the system, new tools that take into account the horizon of the decision taken are necessary. Feature like the availability of new information can be included in a dynamic optimization framework and therefore help mitigate congestion in the system and have positive effects on distribution systems. This study proposes a new algorithm and shows some preliminary results for the use of Energy Storage Systems (ESS) interacting with stochastic sources of generation. The initial motivation came from the study of the adoption of renewables for electricity, and how to better harness the power of sources that are inherently oscillatory in power output. The benefits of ESS in a dynamic optimization go beyond the amount of renewable energy actually dispatched in the system. The current debate and probable adoption of electrified transportation will most likely increase the pressure on local distribution systems. However, the availability of distributed energy will also increase, in the form of energy storage, once the interface between the grid and the power sources in the vehicles is developed in a mass scale.
JF - 2010 IEEE/PES Transmission and Distribution Conference and Exposition: Latin America (T&D-LA)
PB - IEEE
CY - Sao Paulo, Brazil
SN - 978-1-4577-0488-8
DO - 10.1109/TDC-LA.2010.5762985
ER -
TY - CONF
T1 - Risk-based optimal power flow and system operation state
T2 - IEEE Power & Energy Society (PES) General Meeting
Y1 - 2009/07//
SP - 1
EP - 6
A1 - Li, Yuan
A1 - James D. McCalley
KW - AA09-001
KW - AARD
KW - Automatic Switchable Network (ASN)
KW - load flow
KW - optimal power flow (OPF)
KW - power system economics
KW - power system reliability
AB - In this paper, the risk-based optimal power flow is proposed, which minimizes the economic cost considering the system reliability, and a refined system operation state is provided to clarify this approach. In order to obtain better economic benefit than traditional security-constrained optimal power flow, the corrective optimal power flow is used in this work. The reliability is represented by the risk index, which captures the expected impact to the system. This problem is solved by Benders decomposition. The specific designed Benders subproblem will assure that no collapse or cascading overload occurs for the corrective optimal power flow problem. The approach auto-steers the dispatch between different risk level according to the probability and consequence of the upcoming contingency events. Case studies with a six-bus system are presented.
JF - IEEE Power & Energy Society (PES) General Meeting
PB - IEEE
CY - Calgary, Canada
SN - 978-1-4244-4241-6
DO - 10.1109/PES.2009.5275724
ER -
TY - CONF
T1 - An advanced security constrained OPF that produces correct market-based pricing
T2 - 2008 IEEE Power and Energy Society General Meeting
Y1 - 2008/07//
SP - 1
EP - 6
A1 - Robert J. Thomas
A1 - Carlos E. Murillo-Sanchez
A1 - Ray D. Zimmerman
KW - electricity markets
KW - optimal power flow (OPF)
KW - reliability and markets
KW - RM07-002
AB - Security constrained optimal power flow programs are important tools for ensuring correct dispatch of supply while respecting the many constraints imposed by the delivery system. In addition to getting the dispatch right, locational prices must be calculated with equal precision in order to infuse market participants with the proper incentives for operation and investment. In this paper we discuss a co-optimization framework in which contingencies, ancillary services, and network constraints are correctly accounted for in determining both dispatch and price.
JF - 2008 IEEE Power and Energy Society General Meeting
PB - IEEE
CY - Pittsburgh, PA, USA
SN - 978-1-4244-1905-0
DO - 10.1109/PES.2008.4596331
ER -
TY - JOUR
T1 - Risk-Based Security and Economy Tradeoff Analysis for Real-Time Operation
JF - IEEE Transactions on Power Systems
Y1 - 2007/11//
SP - 2287
EP - 2288
A1 - Fei Xiao
A1 - James D. McCalley
KW - AA09-001
KW - AARD
KW - Automatic Switchable Network (ASN)
KW - optimal power flow (OPF)
KW - Power system modeling
KW - power system security
KW - risk analysis
AB - This letter describes a new perspective on balancing system security level with cost for real-time operation. Security level is quantified using risk, which provides that security may be optimized. A risk-based multiple-objective (RBMO) model, considering security and economy together, is compared with the traditional security-constrained OPF (SCOPF) model. A six-bus test system is used to show the merits of RBMO.
VL - 22
IS - 4
JO - IEEE Trans. Power Syst.
DO - 10.1109/TPWRS.2007.907591
ER -