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This paper gives 3000 solutions for reactive power optimization using repeated genetic algorithm. The objective function is minimization of voltage deviations at load buses and the control actions are changes in generator excitations, capacitor switching and tap changing transformers. IEEE30 bus system is the test data and simulated on MATLAB. New data prediction algorithm is given.
This paper considers the problem of selecting a set of residual generators for inclusion in a model-based diagnosis system, while fulfilling fault isolability requirements and minimizing the number of residual generators. Two novel algorithms for solving the selection problem are proposed. The first algorithm provides an exact solution fulfilling both requirements and is suitable for small problems...
In this paper, an approach based on the concept of Model Predictive Control (MPC) is used to control transmission voltages and prevent long-term voltage instability. The MPC model is based on a linearized steady-state system model derived from power flow equations. Simulation results are presented for the case of Nordic32 test system.
In view of bridging the gap between increasing power demand and limited generation, augmentation of renewable resources into existing power systems is gaining importance. Distribution network which includes these small generating sources and loads are called micro-grids which can work either in non-autonomous or autonomous mode. In this regard, this paper attempts at determining the optimal location...
The allocation of ohmic losses in the transmission system with a method that complies with the requisite of cost causality is critical for sending location-specific, efficient economic signals to transmission system users, and to incentivize the efficient use and expansion of the electricity system. In this paper, we employ a formulation of the Incremental Transmission Losses allocation method that...
This paper discusses the problem of loss reduction by the means of reactive power redispatch. The idea is to keep the system security following a transaction. In this sense, identifying the generators most likely to play redispatch is crucial. A sensitivity-based methodology is proposed, so the generators are identified and their reactive power equations are incorporated into the ordinary power flow...
This paper presents a power flow adjustment method for unsolvable power flow equation. The proposed method is based on the line transfer limit and system PV, QV and Pδ curve. New slop indexes are defined to describe the characteristics of the system infeasible critical point. Using the indexes can find the system weak line when system power flow is on the solution boundary. Paper also discussed the...
This paper shows the interest of extending the dynamic parity space fault detection method for fractional systems. Accordingly, a comparison between fractional and rational residual generators using the later method is presented. An analysis of fractional and rational residuals' sensitivity shows the merits of the fractional residual generators. A numerical example illustrating the advantage of using...
Conventional optimization technique suggests that marginal unit generation sensitivity (MUGS) may be calculated based on perturbation at optimality. The calculated MUGS however only applies to the perturbed operating point. Often times it is not advisable to apply this local information to predict generations at another loading level with considerable load change, and therefore another calculation...
In a deregulated electricity market, it may always not be possible to dispatch all of the contracted power transactions due to congestion of the transmission corridors. The ongoing power system restructuring requires an opening of unused potentials of transmission system due to environmental, right-of-way and cost problems which are major hurdles in the expansion of power transmission network. Flexible...
The problem of fault diagnosis in thrusters of autonomous underwater vehicle is studied. Solution of the problem involves residual generation as a result of mismatch between vehicle behaviour and its reference model behaviour followed by decision making via evaluation of the residual. Sensitivity theory based methods are developed for the design of both residual generator and decision making procedure...
The strong coupling between bus voltages and reactive power injections has been widely used in steady state power flow algorithms. In the Newton-Raphson formulation the Jacobian matrix represents small-signal sensitivities relating real and reactive power injections to bus phase angles and voltage magnitudes respectively [1]. Decoupled approaches neglect real power-voltage and reactive power-phase...
This paper presents a sensitivity based congestion management technique based on generation rescheduling and/or load shedding. A sensitivity index which relates the change in line current with respect to change in bus injections is developed to select the participating generators and/or loads. Proposed technique is simulated on IEEE 30 and 118 bus test systems and its effectiveness is illustrated.
In a deregulated electricity market transmission congestion occurs when there is insufficient transmission capacity to simultaneously accommodate all requests for transmission service within a region. One of the most important tasks of independent system operator (ISO) is to manage congestion as it threatens system security and may cause rise in electricity price resulting in market inefficiency....
This paper addresses parameter estimation for hybrid dynamical systems, such as electric power systems, with state-dependent events and time-delayed parametric switching. Previous work dealing with hybrid dynamical systems has addressed the calculation of trajectory sensitivities used in gradient-based parameter estimation methods, as well as the computation of proper sensitivity jump conditions at...
This paper presents multi-objective optimization approach for determining optimal location of distributed generators in deregulated electricity market. Distributed generators optimal location have been obtained in a most suitable zone which has been identified based on the variation of real power flow sensitivity and real power loss sensitivity. The multi-objective function consist maximization of...
Usually, the main purpose of optimal reactive power flow (ORPF) programs is to minimize the total power losses of a network, maintaining the voltage profile within an acceptable range. This model was adopted by almost all the vertically integrated utilities. Nowadays, in the liberalized environment, a new ORPF formulation, aimed at an explicit maximization of the system security, is more suitable...
Due to their reconfigurability and their high density of resources, SRAM-based FPGAs are more and more used in embedded systems. For some applications (Pay-TV,Banking, Telecommunication ...), a high level of security is needed. FPGAs are intrinsically sensitive to ionizing effects, such as light stimulation, and attackers can try to exploit faults injected in the downloaded configuration. Previous...
This paper deals with long-term voltage instability triggered by the outage of transmission or generation equipments. It is shown how the onset of voltage instability could be detected in real-time from post-disturbance bus voltages provided by phasor measurement units (PMUs), assuming observability of the whole region prone to voltage instability. An extended set of equilibrium equations is fitted...
A new framework to estimate dynamic parameters of synchronous generator is proposed in this paper. The methodology does not require special tests but uses disturbance data collected from the system without disconnecting the generator from the grid. It requires measurements that are easily available, more precisely, the 3-phi currents and voltages, the field voltage and the mechanical rotor speed....
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