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System ability to continuously supply load is very important. One of the factors that influence that system ability is frequency and voltage stability. Frequency and voltage stability need to be considered during electrical power planning and operating to avoid system instability that can cause system blackout. Load shedding need to be done to restore the system into normal condition after interference...
One of the biggest threats for the security of power grids are congestion of cross-border lines and congestion in the network itself as result of parallel flows. Nowadays, occurrence of congestion is a result of limited network transfer capacities as a direct consequence of increased power transactions. One of the reasons for cross-border congestions are the unreal cross-border capacities calculations...
We examine the robustness of solar capacity-value estimates to three important data issues. The first is the sensitivity to using hourly averaged as opposed to subhourly solar-insolation data. The second is the sensitivity to errors in recording and interpreting load data. The third is the sensitivity to using modeled as opposed to measured solar-insolation data. We demonstrate that capacity-value...
This paper proposes the use of Demand Response programs for congestion management. Two DR programs are implemented: Time-of-Use (TOU) and Emergency Demand Response Program (EDRP).A combination of single period modeling and multi-period modeling on the basis of elasticity concept is used to model the DR programs. The model that has been put forward is implemented on load data varying on the hourly...
Wind turbine system (WTS) now a day has turned out to be exceptionally useful technique to minimize the centralization of electrical power particularly in provincial territories and rural areas. In any grid connected WTS there are alternatives for receiving reactive power from main grid but if it is islanded or made off grid in that case we need to look for different choices for voltage profile improvement...
Based on the equivalence method of sensitivity consistency and component particularity representation, an equivalent power flow model and a minimum load shedding model are proposed. With these two models, an equivalent reliability evaluation method considering the equivalence of external system is developed. Because the sensitivity information, voltage support, power support and transfer characteristics...
An efficient and agile load-shedding model based on power flow tracing is proposed in this paper, which can effectively alleviate the high stress of power system in some emergency cases. First, calculate the distribution coefficient of bus to the overloaded branch by power flow tracing. Then, find out the loads and generators that have the most impact on the overloaded branch, i.e. those that linked...
Blackouts in large interconnected power system can cause damage to equipment of power plants, interruption of production cycles, and great economic losses. In order to avoid blackouts from occurring in the power system, an effective forced islanding scheme with a suitable load shedding scheme can be used, for improving power system security. Further, a suitable restoration sequence is required to...
This paper proposes an optimal method to plan and dynamically operate the distributed generation (DG) based on the modified nondominated sorting genetic algorithm II (NSGA-II). First, the uncertainty of load and DG (photovoltaic panels) output are considered. Daily summer load data and ideal photovoltaic (PV) panels output data are taken from a local electrical company in Albuquerque. To model the...
With the rapid development of both the size and intricacy of the power system, power system is gradually approaching its operating limit. System islanding is usually considered as the ultimate control action to preserve as many stable areas as possible. The islanding strategy plays an important role in the power system restoration as it determines whether the islands can make safe and steady operation...
Blackouts in large interconnected power system can cause damage to equipment of power plants, interruption of production cycles and great economic losses. In order to avoid these blackouts, a forced islanding scheme with suitable restoration sequence will be effective. This paper proposes an algorithm that identifies the risk during an outage and forcefully splits the system into predefined islands...
The structural cost of offshore wind energy can be drastically reduced by the development of floating wind turbines. However, the design of a feedback controller for rotor speed control of such turbines faces fundamental bandwidth limitations because of the presence of nonminimum phase zeros. New developments in lidar technology enable turbines to measure the incoming wind and use the measurements...
This paper assumes significant amount of protracted local loss of the generation capability (approximately 20% of the total capacity), and examines the resulting load changes in the loop system, which likely result in creating considerable power flow differences in such a system. We then propose the use of phase shifting transformers (PSTs) to alleviate load differences among transmission lines, allowing...
With introduction of wind power distributed generation into the distribution system, the reactive power drawn from and injected to the system are affected. This further affects the load bus voltages due to which on load tap changers of the transformers respond to maintain the terminal voltage. Due to the intermittent behaviour of wind, the reactive power requirements of wind generator vary. This may...
The paper introduces an approach to investigate voltage sags, which are caused by large generator rotor swings following a transient disturbance. Therefore, the method exploits sensitivities derived from the algebraic network equations. These provide information on the impact of a generator on the voltage magnitude at a load bus and the effect of load variation on the generator's power injection....
This work deals with a new formulation for the Direct Current Optimal Power Flow (DCOPF) including the corrective actions related to the phase shifting transformers. The formulation is based on the outage of generators and/or branches modelled as fictitious injections of active power. The inclusion of the sensitivities of the phase shifting transformer with respect to the injected powers is one of...
This paper proposes a peak load management scheme to transfer certain consumers onto local non embedded generators during peak load period and improve the voltage profile correspondingly alleviating the voltages at nodes where the voltage is less than the specified value. These non-embedded generators depending on operating characteristics and location, can mitigate under voltage profile and help...
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.
This paper summarizes ongoing research in the application of intelligent methods to the design, modeling, simulation and control of microgrids including optimal design of microgrids, and centralized and decentralized control.
Scarcity of power is a common problem in developing countries like Bangladesh. The demand of fossil fuel as a conventional component for producing power, is not adequate. Merely, It is located in a region where prominent amount of solar irradiation and water flow can be accumulated for rendering power. In this paper, an integrated hybrid energy system has been discussed. This hybrid energy system...
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