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This two-part paper surveys the frequency and voltage control ancillary services in power systems from various parts of the world. In this first part, the nomenclature used to describe active power reserves across 11 systems is first reviewed in order to facilitate the comparison of frequency control ancillary services. The essential technical features of frequency and voltage control ancillary services are then described. Finally, the technical requirements adopted in eight jurisdictions (North America, continental Europe, Germany, France, Spain, the Netherlands, Belgium, and Great Britain) are compared. The companion paper surveys the economic features of these ancillary services. [ABSTRACT FROM AUTHOR]

The solution of power system constraints is an important issue that has to be addressed to achieve a fair operation of a competitive electricity market. In the Spanish electricity market, the System Operator (SO) is in charge of determining the technical feasibility of the generation dispatch provided by the Market Operator (MO). An optimal solution method of power system constraints in the Spanish market must take into account the connection of off-line units to solve both branch overloads and voltage constraints, the adjustment of voltage control resources, the solution of the postulated n-I and n-2 contingencies with a preventive criteria and the coupling of the solution in the 24 hourly scenarios due to the start-up cost of nonconnected units. This paper details the management of power system constraints in the Spanish market, and contains a comprehensive review of solution methods of power system constraints. In addition, the paper proposes a novel approach to solve Spanish power system constraints that overcomes the limitations of existing methods, by decoupling the solution of branch overloads and voltage constraints. [ABSTRACT FROM AUTHOR]

The level of secondary reserve needed in a power system is traditionally settled by system operators according to engineering criteria. This paper proposes a novel methodology to determine the optimum level of secondary reserve based on both engineering and economic criteria. Within the proposed approach a price elastic-quantity demand curve for the secondary reserve is built. This approach assumes that the provision of secondary reserve is made under a competitive market. In this market, the supply curve that collects the bids from generators providing secondary reserve is matched with the calculated elastic demand cost curve. The cross of the supply and demand curves determines the optimal level of secondary reserve and the price for provision of the service. The developed approach is illustrated with a case study based on the current day-ahead secondary reserve market in Spain. [ABSTRACT FROM AUTHOR]

In this paper, an efficient method based on a new fuzzy neural network is proposed for short-term price fore- casting of electricity markets. This fuzzy neural network has inter-layer and feed-forward architecture with a new hypercubic training mechanism. The proposed method predicts hourly market-clearing prices for the day-ahead electricity markets. By combination of fuzzy logic and an efficient learning algorithm, an appropriate model for the nonstationary behavior and outliers of the price series is presented. The proposed method is examined on the Spanish electricity market. It is shown that the method can provide more accurate results than the other price forecasting techniques, such as ARIMA time series, wavelet-ARIMA, MLP, and RBF neural networks. [ABSTRACT FROM AUTHOR]