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Carmel, IN, United States

The Midcontinent Independent System Operator, Inc., formerly named Midwest Independent Transmission System Operator, Inc. is an Independent System Operator and the Regional Transmission Organization that provides open-access transmission service and monitors the high voltage transmission system throughout the Midwest United States, and Manitoba, Canada and more recently integrated a southern region which includes much of Arkansas, Mississippi, and Louisiana. MISO operates one of the world’s largest real-time energy markets. Wikipedia.

Gu W.,Nanjing Southeast University | Wu Z.,University of Birmingham | Bo R.,Midwest Independent Transmission System Operator | Liu W.,Nanjing Southeast University | And 3 more authors.
International Journal of Electrical Power and Energy Systems | Year: 2014

A combined cooling, heating and power (CCHP) microgrid with distributed cogeneration units and renewable energy sources provides an effective solution to energy-related problems, including increasing energy demand, higher energy costs, energy supply security, and environmental concerns. This paper presents an overall review of the modeling, planning and energy management of the CCHP microgrid. The performance of a CCHP microgrid from the technical, economical and environmental viewpoints are closely dependent on the microgrid's design and energy management. Accurate modeling is the first and most important step for planning and energy management of the CCHP microgrid, so this paper first presents an review of modeling of the CCHP microgrid. With regard to planning of the CCHP microgrid, several widely accepted evaluation methods and indicators for cogeneration systems are given. Research efforts on the planning methods of the CCHP microgrid are then introduced. Finally, the energy management of the CCHP microgrid is briefly reviewed in terms of cogeneration decoupling, control strategies, emission reduction and problem solving methods. © 2013 Elsevier Ltd. All rights reserved. Source

Bo R.,Midwest Independent Transmission System Operator | Li F.,University of Tennessee at Knoxville
Electric Power Systems Research | Year: 2012

This paper presents an analytical approach for studying the impact of load forecasting uncertainty on locational marginal price (LMP), in electricity wholesale market. The random nature of load brings in uncertainty in LMP through a market clearing model, also known as an optimal power flow (OPF) problem. This work is built on alternating current OPF, a close representation of the actual problem where power losses are accurately modeled. In the context of load being a normally distributed random variable, the probabilistic LMP concept under ACOPF is firstly examined to be a mixed random variable assuming both continuous and discrete values. Then, with the LMP versus load model, the probability density function (PDF) and cumulative density function (CDF) of probabilistic LMP are formulated and shown to be differentiable almost everywhere. The derived PDF formulation reveals an interesting fact that LMP does not follow a normal distribution even when load is normally distributed. Rather, its PDF presents a piece-wise partial normal distribution pattern due to the LMP step-change phenomenon. Further, the expected value of the probabilistic LMP and its sensitivity are derived. The proposed analytical approach can be useful for power market participants in evaluating and hedging financial risks associated with LMP uncertainty. The validity and effectiveness of the proposed method will be exemplified on a modified PJM 5-bus system and the IEEE 118-bus test system. © 2012 Elsevier B.V. All rights reserved. Source

Bo R.,Midwest Independent Transmission System Operator | Li F.,University of Tennessee at Knoxville | Tomsovic K.,University of Tennessee at Knoxville
International Journal of Electrical Power and Energy Systems | Year: 2012

Critical Load Levels (CLLs) are load levels at which a new binding or non-binding constraint occurs. Successful prediction of CLLs is very useful for identifying congestion and price change patterns. This paper extends the existing work to completely solve the problem of predicting the Previous CLL and Next CLL around the present operating point for an AC Optimal Power Flow (ACOPF) framework. First, quadratic variation patterns of system statuses such as generator dispatches, line flows, and Lagrange multipliers associated with binding constraints with respect to load changes are revealed through a numerical study of polynomial curve-fitting. Second, in order to reduce the intensive computation with the quadratic curve-fitting approach in calculating the coefficients of the quadratic pattern, an algorithm based on three-point quadratic extrapolation is presented to get the coefficients. A heuristic algorithm is introduced to seek three load levels needed by the quadratic extrapolation approach. The proposed approach can predict not only the CLLs, but also the important changes in system statuses such as new congestion and congestion relief. The high efficiency and accuracy of the proposed approach is demonstrated on a PJM 5-bus system and the IEEE 118-bus system. © 2012 Elsevier Ltd. All rights reserved. Source

Gu Y.,Midwest Independent Transmission System Operator | McCalley J.D.,Iowa State University | Ni M.,State Grid Electric Power Research Institute of China
IEEE Transactions on Sustainable Energy | Year: 2012

In this paper, a generation expansion planning model and a transmission expansion planning model are proposed to inform investment decisions from the perspectives of generation companies and ISOs, respectively. Interactions between large-scale wind integration and transmission system planning are analyzed, and a new computational procedure of system expansion planning that coordinates generation and transmission investment is presented. The cooptimization of energy and ancillary services markets is considered to capture the impacts of wind power on the operation of the electric system. Benders decomposition is employed to reduce the overall computation time. © 2010-2012 IEEE. Source

Bo R.,Midwest Independent Transmission System Operator | Li F.,University of Tennessee at Knoxville
IEEE Transactions on Power Systems | Year: 2011

An accurate estimation of critical load levels (CLLs) is beneficial in evaluating the confidence level for the predicted locational marginal prices (LMPs) in power markets. This paper proposes an efficient algorithm to quickly identify CLLs under the with-loss-DCOPF framework. The proposed method approximates the trajectory of DCOPF solutions with respect to the system load variations. The quadratic coefficients of the trajectory can be efficiently obtained by solving a small-scale nonlinear system of equations formed by the variable substitution method, which does not require additional OPF runs and is thus more computationally efficient than existing methods such as binary search and interpolation. The obtained trajectory can be used for a quick calculation of OPF solutions without re-running OPF. Further, through trajectory extrapolation, new congestions and other binding constraints can be identified simultaneously with the CLL predictions. Particularly, the proposed method is not restricted to a specific DCOPF-based model and can be easily applied to other DCOPF-based variants. Numeric studies on a revised IEEE 30-bus system are presented to illustrate the high computational efficiency and accuracy of the approach. It is further tested on the IEEE 118-bus system using four different DCOPF-based models to illustrate its model adaptability. © 2006 IEEE. Source

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