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This paper presents a model to include a security constraint for wind power plant in a hydrothermal dispatch problem. The proposed Unit Commitment (UC) is an augmented problem to take into account different scenarios of wind speed during the day. The wind farms are represented by a linear model that the generations are considered proportional to the availability of wind. The proposed optimization...
By influencing the demand side by means of price signals (Demand Response) additional flexibility potential in electric supply systems can be provided. However, by influencing the demand side typical consumption patterns of previously unaffected consumers are changed. This will lead to increasing uncertainty in load forecasting. This paper deals with the forecast of load time series in consideration...
nowadays, power system tends to be operated in heavily stressed load, which can cause voltage stability problem. Moreover, occurrence probability of contingency is increasing due to growth of power system size and complexity. This paper proposes a new preventive control scheme based on voltage stability and security monitoring by means of wide area monitoring systems (WAMS). The proposed control scheme...
Due to the increasing share of distributed energy resources, which will be integrated into the electrical grid within the next decades, innovative grid structures and management concepts are required to ensure a reliable supply of electrical energy in the future. The integration of energy storage devices will become more and more important in this context to ensure the stability of the electrical...
Distribution system state estimation (DSSE) is an essential tool in active distribution grids in order to enhance the awareness of the power system operators regarding the state of the distribution system. One of the peculiarities of the DSSE is the lack of adequate real-time measurements. Thus, in this paper a three-phase DSSE algorithm enhanced with an advanced approach for modeling pseudomeasurements...
Recent technological developments have facilitated the emergence of smart grids. In the smart grid perspective, metering and communication functionalities of the grid are greatly enhanced, thus boosting its observability and load management capabilities. This is an ideal scenario which is frequently encountered in contemporary literature. Unfortunately, in reality, operational and financial reasons...
This paper presents optimal transmission systems reinforcements in the existing lines considering (n-1) criterion for transmission outages. The proposed reinforcement minimizes the total investments costs and ensures a viable operation of the system under contingencies. The formulation includes, in an Optimal Active Power Flow (OAPF), the relationship between the inductive susceptance and transmission...
Risk-based security indexes can be used as a constraint in OPF to determine the most economic generation dispatch while ensuring that the risk of power system operation stays below a given value. Existing approaches only limit the total risk, which can result in some system states having significantly higher values of risk compared to others. In this paper, a risk-constrained AC OPF that limits the...
This paper presents the situation of the photovoltaic power plants nationwide (Romania) and in particular the situation of the photovoltaic (PV) power plants in Mureş county. It also describes the minimal technical conditions that a PV power plant must fulfill before it is connected to the national grid. A particular case study consists of the impact that the PV power plant in Chirileu has on the...
This paper presents use of no-load current harmonic analysis to detect presence of inter-turn fault at incipient stage. At steady state, third and fifth harmonic components are predominant in transformer no-load current. Inception of fault results in decrease in THD and increase in increase in primary current. Based on reduction of total harmonic distortion (THD) of each phase and simultaneous increase...
In this paper two different methods to estimate the proximity of the system to the Maximum Loading Point (MLP) are proposed. They are compared with a specific method recently published that uses the Cubic Spline Extrapolation (CSE) for estimating the MLP. All three methods are based on tracking the Thévenin Equivalent (TE) of the system as seen from the load buses using data from Phasor Measurement...
This paper proposes an optimal control strategy for participation of wind farms (WFs) in primary frequency control. In this strategy, we exploit wake interaction in a WF to maximise the total kinetic energy (KE) of the wind turbines' (WTs') rotating masses in the WF, and optimally deploy this KE after a frequency event to reduce the frequency nadir, by controlling the rate of change of the rotor speed...
Distribution system operators will gather an increasing amount of electricity data from the lower level of the grid to be able to cope with several challenges, such as an increase of distributed, heterogeneous energy production, local storage, and electric vehicles. Most DSOs are not yet prepared for collecting, storing and processing these large amounts of data. This paper introduces a method for...
The impact of several technologies of dispersed generation on the fault current flow in regular distribution networks is discussed. The short-circuit current behavior of conventional generators (for instance those used in heat and power plants), of generators equipped with full convertors and of double fed induction generators (DFIG) are described from the perspective of a distribution system operator...
Low-frequency, electro-mechanically induced, inter-area oscillations have in the past, posed a serious threat to the stability of interconnected power systems. Wide Area Monitoring, Protection and Control (WAMPAC) systems based on wide-area measurements can be exploited to address the inter-area oscillation problem. This work develops a modular software architecture for a prototype WAMPAC control...
Machine learning methods are the main stream algorithms applied in short term load forecasting. However, typical machine learning methods consisting of Artificial Neural Network (ANN) and Support Vector Regression (SVR) have deficiencies hard to overcome, such as easy to be trapped in local optimization (for ANN) or hard to decide kernel parameter and penalty parameter (for SVR). On the other hand,...
Two approaches for modelling the impact of ambient conditions on powerlines have been developed and recognised as international standards. Methods of thermal analysis of powerlines have been collated and presented in standards by both the Institute of Electrical and Electronics Engineers (IEEE) and International Council on Large Electric Systems (Conseil International des Grands Réseaux Électriques,...
The energy resource management is becoming increasingly important and complex, because of the growing use of distributed generators and electric vehicles connected to the distribution network. This paper presents a platform to be used by virtual power players regarding the energy resource management in smart grids and considering day-ahead, hour-ahead, and real-time time-horizons. This method considers...
This work is about the in-process visualization of multi-dimensional datasets recorded by compressed event-driven energy metering methods. The main goal of this work is to provide easy visual form to better understand energy transformations caused by real-life processes.
The Dutch Transmission System Operator TenneT TSO B.V. is responsible for the Dutch electricity grids with voltages of 110 kV to 380 kV. The company is required to guarantee the Security of Supply at all times, and must comply with both national and international legislation and agreements. Economic efficiency and market facilitation are prompting an increase in interconnection capacity between European...
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