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This paper describes an innovative scheme based on a pluralistic load frequency control (LFC) and aimed at performing cross-border power control, secondary frequency regulation, and internal congestion resolution. Such an LFC scheme applies to a pluralistic block of control areas, whose regulators can adjust the production of their generators with respect to the request of the coordinating area when the power flows through grid sections exceed their maximum admissible values. This paper introduces the theoretical aspects and functional design of such an advanced LFC scheme, capable of controlling at the same time the cross border exchanges of the pluralistic block and the power flows between network subareas defined as market zones. Simulations on the Italian power system show the performance, main advantages, and limits of the proposed control method. [ABSTRACT FROM AUTHOR]

This paper considers a profit-maximizing thermal producer that participates in a sequence of spot markets, namely, day-ahead, automatic generation control (AG C), and balancing markets. The producer behaves as a price-taker in both the day-ahead market and the AGC market but as a potential price-maker in the volatile balancing market. The paper provides a stochastic programming methodology to determine the optimal bidding strategies for the day-ahead market. Uncertainty sources include prices for the day-ahead and AGC markets and balancing market linear price variations with the production of the thermal producer. Results from a realistic case study are reported and analyzed. Conclusions are duly drawn. [ABSTRACT FROM AUTHOR]

This paper proposes a novel technique for representing system security constraints that properly include voltage stability limits in the operation of competitive electricity markets. The market-clearing algorithm is modeled as a voltage stability constrained optimal power flow (OPF) problem, while the distance to the closest critical power flow solution is represented by means of a loading parameter and evaluated using a continuation power flow (CPF) technique. Sensitivities obtained at the OPF step are used to estimate power directions for the CPF method, while the CPF analysis provides the loading parameter to be used in the OPF problem based on an N - 1 contingency criterion. The OPF and the CPF steps are repeated until the maximum loading parameter is found, thus providing optimal solutions considering both proper market conditions and security margins. Two benchmark systems with both supply and demand bidding are used to illustrate and test the proposed technique. [ABSTRACT FROM AUTHOR]

Tidal stream generation is a form of renewable energy that is predicable but variable in nature. The paper initially identifies the tidal resource around Ireland, utilizing the most appropriate and developed tidal energy technology, thus providing a potential magnitude and output profile. Methods of deployment and control, including the down rating of the generator relative to turbine size and operational output reduction, are suggested to reduce capital cost, increase the capacity factor and reduce the impact on the grid system. The combination of the potential resource and the application of control methods provide the basis to study the effect on the grid system in terms of ramp rate and the demand profile. The same inputs also provide the ability to analyze generator characteristics such as the capacity credit. [ABSTRACT FROM AUTHOR]

Within an optimal power flow market clearing framework, this paper provides expressions to compute the sensitivities of locational marginal prices with respect to power demands. Sensitivities with respect to other parameters can also be obtained. An example and a case study are used to illustrate the expressions derived. [ABSTRACT FROM AUTHOR]

Performance specifications place restrictions on the dynamic response of many systems, including power systems. Quantitative assessment of performance requires knowledge of the bounding conditions under which specifications are only just satisfied. In many cases, this limiting behavior can be related to grazing phenomena, where the system trajectory makes tangential contact with a performance constraint. Other limiting behavior can be related to time-driven event triggering. In all cases, pivotal limiting conditions can be formulated as boundary value problems. Numerical shooting methods provide efficient solution of such problems. Dynamic performance. assessment is illustrated in the paper using examples drawn from protection operation, transient voltage overshoot, and induction motor stalling. [ABSTRACT FROM AUTHOR]