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Uncertainty in power systems operations has been traditionally managed by multistage decision making and operating reserve requirements. A familiar example of multistage decisions is day-ahead unit commitment and real-time economic dispatch. An alternate approach for managing uncertainty is a stochastic formulation, which allows the explicit modeling of the sources of uncertainty. This paper compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem. Numerical studies show that unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach in terms of both economics and reliability metrics. Index Terms--Economic dispatch, operating reserve, optimization, Monte Carlo simulation, reliability, stochastic programming, unit commitment.

The evolution toward the standardized market design (SMD) is presented in this paper with references to the market developments in New Zealand, Australia, PJM, ISO-NE, and ERCOT. In the development of market designs, two main objectives--market liquidity facilitating bilateral trading and pricing efficiency facilitating congestion management, have been pursued. The efforts to balance the seemingly conflicting objectives led to most markets designed with a uniform or zonal pricing model. Introduction of locational marginal pricing and evolution of transmission rights from physical to financial form made it possible to harmonize the potentially conflicting goals in a market design. The close coupling between energy and ancillary services requires that markets for these commodities be carefully coordinated. Different operational practices and reliability standard requirements have led to major differences in ancillary service market designs. Index Terms--Ancillary service markets, electricity market, financial transmission rights, locational marginal pricing, standardized market design.

On-line dynamic security analysis has recently become realistic due to advances in analytical techniques and computer technology. This paper presents experience from implementation of the on-line transient stability analysis system at the B.C. Hydro control center. Implementation of that on-line system was conceived as part of a broader on-line dynamic security analysis system. As a description of what is believed to be the first implementation of a full-scale on-line transient stability analysis, this paper provides insight into the design and evolution of on-line dynamic security analysis. Keywords: Dynamic Security, Transient Stability, Operations, System Control

This paper discusses the design concept and usage of the Power System Toolbox, a Matlab-power system dynamics simulation and control design package. The motivation for developing the package is to provide a flexible environment for teaching power system simulation techniques and control design concepts to advanced undergraduate and graduate students, and for graduate students to perform research and development on power systems. The package can be executed without modification on all platforms that Matlab supports, including IBM PC, Macintosh and many workstations.

The integration of distributed energy resources into a virtual power plant (VPP) can realise the scale merit. This study presents a novel approach for determining the optimal offering strategy of a VPP participating in the day-ahead (DA), the spinning reserve (SR), and the real-time (RT) markets. To hedge against multi-stage uncertainties, the authors propose a robust mixed integer linear programming optimisation model that comprises four levels: (i) the optimal DA energy and reserve dispatch; (ii) the worst-case realisation of uncertainties involved in DA market energy prices, SR market capacity prices, stochastic power production, and called balancing power; (iii) the optimal RT energy re-dispatch; and (iv) the worst-case realisation of uncertain RT market energy prices. Moreover, a tractable solution method based on strong duality theory and the column-and-constraint generation algorithm to solve the proposed four-level formulation was developed. Finally, numerical results for a realistic case study demonstrate the efficiency and applicability of the proposed approach. The commercial benefits of this strategy are also evaluated. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) electric power has been widely employed to satisfy rising energy demands because inexhaustible renewable energy is environmentally friendly. In order to mitigate the impact caused by the uncertainty of solar radiation in grid-connected PV systems, a hybrid method based on a deep convolutional neural network (CNN) is introduced for short-term PV power forecasting. In the proposed method, different frequency components are first decomposed from the historical time series of PV power through variational mode decomposition (VMD). Then, they are constructed into a two-dimensional data form with correlations in both daily and hourly timescales that can be extracted by convolution kernels. Moreover, the time series of residue from VMD is refined into advanced features by a CNN, which could reduce the data size and be easier for further model training along with meteorological elements. The hybrid model has been verified by forecasting the output power of PV arrays with diverse capacities in various hourly timescales, which demonstrates its superiority over commonly used methods. [ABSTRACT FROM AUTHOR]

Since the Federal Energy Regulatory Commission's (FERC) order no. 888 has mandated the establishment of unbundled electricity markets in the newly deregulated environment, competitive bidding of ancillary services, along with bidding of energy, becomes increasingly important. In this paper, an optimization-based framework for solving a multi-commodity electricity market dispatch problem is presented. In compliance with New England Power Pool (NEPOOL) Market Rules and Procedures, a hybrid dispatch method which combines the sequential dispatch method with the joint dispatch method is proposed to solve the energy and ancillary dispatch problem for ISO New England (ISO-NE). Numerical results on a 6-unit test system and the 324-unit ISO-NE system are included. Index Terms--Automatic generation control, deregulation, electricity market, energy and reserve dispatch, system operator.