The Experts below are selected from a list of 13461 Experts worldwide ranked by ideXlab platform
A. Castro - One of the best experts on this subject based on the ideXlab platform.
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Self-excitation Operating Constraint for generators connected to DC lines
IEEE Transactions on Power Systems, 1999Co-Authors: P.g. Mclaren, A.m. Gole, D. Fedirchuk, A. CastroAbstract:In a generating station linked to a main power system through an HVDC transmission line, a load rejection of the HVDC line may cause generators in the station to become self-excited, resulting in a severe system overvoltage. It may also cause damage to generator exciters if negative current is not allowed to flow in the exciter. This paper derives the self-excitation Operating Constraint for generators Operating in such a system. Results show that a self-excitation Operating Constraint greatly reduces the Operating zone of a generator in such a station. However, this Operating Constraint can be effectively improved by self-excitation protection systems to remove surplus AC filter capacitive VArs.
Mohamed Ebeed - One of the best experts on this subject based on the ideXlab platform.
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A comprehensive model of C-UPFC with innovative Constraint enforcement techniques in load flow analysis
International Journal of Electrical Power & Energy Systems, 2018Co-Authors: Salah Kamel, Mohamed EbeedAbstract:Abstract Center-node Unified Power Flow Controller (C-UPFC) is a recent developed Flexible AC Transmission System (FACTS) device. C-UPFC is a combined shunt-series controller that connected at the midpoint of transmission lines to control various parameters such as, voltage magnitude at midpoint of line, active and reactive powers flow at both ends of line. This paper proposed an efficient modelling with handling Operating Constraints of C-UPFC device load flow solution. The proposed model based on power injection approach, where the parameters of C-UPFC are represented as function of the specified control values to keep the original structure of Jacobian matrix as it is. The Operating Constraints of C-UPFC including, the series injected voltages, the series current passing through converters, shunt injected voltage, the injected current of shunt converter, and exchanged power among converters are handled by an developed innovative methods. The developed handling methods based on modifying and updating the specified values as a function of maximum limit of the Operating Constraints. The proposed C-UPFC model with developed handling Operating Constraint methods implemented in IEEE 30-bus and IEEE 118-bus test systems. The obtained simulation results show the robustness and feasibility of the proposed model in load flow and superiority of the developed methods over the conventional methods for handling the Operating Constraints of C-UPFC.
F. Guhl - One of the best experts on this subject based on the ideXlab platform.
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Optimization of drinking water network: incorporating continuity Constraints
2000Co-Authors: F. GuhlAbstract:The optimization of production and transport costs in a drinking water network has been modelized using various operational research methods in recent years. For several years we have been building models used on large water networks, managed in real time. For short calculation times, linear programming has been chosen. Our optimization model is based on an objective function that minimizes the daily proportional costs and on physical Constraints such as tank size. In order to calculate the flows being able to forward on the network an hydraulic model is used. In certain networks, one Constraint has not yet been incorporated into optimization models. It is associated with the Operating conditions of the water treatment plant. To avoid problems with water quality, a waterworks must be able to operate continuously. The problem is difficult to solve because BellmanÖs principle of optimality cannot be applied. To take account of this extra Operating Constraint, we propose a method based on linear programming with mixed variables. We introduce set-up, stop and start-up variables. The optimization model is resolved using the Cplex Solver. The Solver uses several shortcuts that reduce the time taken by a conventional branch and bound algorithm. This method provides satisfaction by maintaining computing times compatible with real time network management. For example, we can solve the optimization of a real network with two different resources (river and groundwater), five tanks supplying 20,000 inhabitants in about 30 seconds.
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Continuity Constraint in optimization of water supply
1999Co-Authors: F. GuhlAbstract:The optimization of production and transport costs in a drinking water network has been modelized using various operational research methods in recent years. In certain networks, there exists a Constraint, which has not yet been incorporated into this type of model. The Constraint is associated with the Operating conditions of the water treatment plant. To avoid problems with water quality, a water works must be able to operate continuously. This problem is difficult to solve because one cannot apply the Bellman's principle of optimality.To take account of this extra Operating Constraint, we propose a method based on linear programming with mixed variables. This method provides satisfaction by maintaining computing times compatible with real time network management.
P.g. Mclaren - One of the best experts on this subject based on the ideXlab platform.
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Self-excitation Operating Constraint for generators connected to DC lines
IEEE Transactions on Power Systems, 1999Co-Authors: P.g. Mclaren, A.m. Gole, D. Fedirchuk, A. CastroAbstract:In a generating station linked to a main power system through an HVDC transmission line, a load rejection of the HVDC line may cause generators in the station to become self-excited, resulting in a severe system overvoltage. It may also cause damage to generator exciters if negative current is not allowed to flow in the exciter. This paper derives the self-excitation Operating Constraint for generators Operating in such a system. Results show that a self-excitation Operating Constraint greatly reduces the Operating zone of a generator in such a station. However, this Operating Constraint can be effectively improved by self-excitation protection systems to remove surplus AC filter capacitive VArs.
Salah Kamel - One of the best experts on this subject based on the ideXlab platform.
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A comprehensive model of C-UPFC with innovative Constraint enforcement techniques in load flow analysis
International Journal of Electrical Power & Energy Systems, 2018Co-Authors: Salah Kamel, Mohamed EbeedAbstract:Abstract Center-node Unified Power Flow Controller (C-UPFC) is a recent developed Flexible AC Transmission System (FACTS) device. C-UPFC is a combined shunt-series controller that connected at the midpoint of transmission lines to control various parameters such as, voltage magnitude at midpoint of line, active and reactive powers flow at both ends of line. This paper proposed an efficient modelling with handling Operating Constraints of C-UPFC device load flow solution. The proposed model based on power injection approach, where the parameters of C-UPFC are represented as function of the specified control values to keep the original structure of Jacobian matrix as it is. The Operating Constraints of C-UPFC including, the series injected voltages, the series current passing through converters, shunt injected voltage, the injected current of shunt converter, and exchanged power among converters are handled by an developed innovative methods. The developed handling methods based on modifying and updating the specified values as a function of maximum limit of the Operating Constraints. The proposed C-UPFC model with developed handling Operating Constraint methods implemented in IEEE 30-bus and IEEE 118-bus test systems. The obtained simulation results show the robustness and feasibility of the proposed model in load flow and superiority of the developed methods over the conventional methods for handling the Operating Constraints of C-UPFC.