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In this paper, a PV energy source has been connected to a flywheel (FW) for short term energy storage in addition to a battery (BAT) for long term energy storage. The purpose of this system is to serve as a part of a shipboard power system as means to deal with large transient loads. In order to make a robust power system for such loads, we propose a flywheel connected to a dc motor and connect this...
This paper presents voltage transient analysis of a proposed 3MW permanent magnet synchronous generator (PMSG) wind power generation system (WPGS) using a real time digital simulator (RTDS). The WPGS that is modeled with realtime digital simulator (RTDS) and RSCAD simulators are characterized for voltage transient analysis. Furthermore, a newly actual controller-hardware-in-the-loop simulation (CHILS)...
In response to the governmental policy of saving energy sources and reducing CO2, and carry out the resident quality of local; this paper proposes a new method for a non-intrusive energy management (NIEM) system in smart home to implement the load identification of electric equipments and establish the electric demand management. Non-intrusive energy management techniques were often based on power...
This paper describes the evolution of procedures to protection relays performance testing. In the early days, the measurement and calibration of relays were made by analog devices and instruments that basically provided the steady-state tests. In the 70's came the electronic test equipment. With the passage of time have evolved, providing a full range of dynamic tests. With technological advances,...
Reportedly, switching operation in gas insulated substation (GIS) leads to deformation of transformer winding and bushing failures. This paper presents practicable method that is investigated for mitigation of overvoltage magnitude and resonance frequency amplitude of very fast transients (VFT) at the power transformer. Properties of this method are simple and inexpensive with at least changes in...
This paper deals with the automatic classification of Power Quality (PQ) transients according to their amplitudes and frequencies, and following the geometrical pattern established via higher-order statistical measurements. The clustering is achieved thanks to the third and fourth-order features associated to the electrical anomalies, which in turn are coupled to the 50-Hz power-line. The main contribution...
Empirical mode decomposition (EMD) approximate entropy and least squares support vector machines (LS-SVM) with bacterial colony chemotaxis (BCC) were used to detect the fault signals in single phase earth, and then distinguish the transient faults and permanent faults on transmission lines. After faults occur, different kinds of faults have different complex levels of voltage transient signals which...
Modern numerical relays often incorporate the logic for combined single and three-phase auto-reclosing scheme; single phase to earth faults initiate single-phase tripping and reclosure, and all the other faults initiate three-phase tripping and reclosure. Accurate faulted phase selection is required for such a scheme. This paper presents a novel scheme for detection and classification of faults on...
A new technique for fast detection of power islands in a distribution network, which uses transient signals generated during the islanding event is investigated. Performance comparison of several pattern recognition techniques in classifying the transient generating events as islanding or non-islanding is presented. Features for the classifiers are extracted using the Discrete Wavelet Transform of...
The Modeling methods for elements (equipments) in the primary circuits of Gas Insulated Substation (GIS) are discussed and summarized. The EMTP is used to set up the simulation model of the primary and secondary circuits of an 110kV GIS and the Very Fast Transient Overvoltage (VFTO) and conducted interference caused by swiching operations traveling to the secondary circuits are calculated. The so-formed...
During early stage of primary restoration process, unexpected Overvoltages may happen due to nonlinear interaction between the unloaded transformer and the transmission system. The most effective method for the limitation of the switching overvoltages is controlled switching since the magnitudes of the produced transients are strongly dependent on the closing instants of the switch. We introduce a...
The quality of electricity supply has become a major concern of electric utilities in power system. In order to acquire the improved power quality, it is required to know the sources of power quality disturbances and find ways to mitigate them. This paper presents a new approach to detect and classify power quality disturbances based on wavelet transformation and neural network. By means of wavelet...
The power quality issues have become an exponentially demanding research field for electric utilities and customers, which usually involve transient variation in power supply voltage or current. This paper presents a new method using wavelet transformation and neural network, investigating the power quality in qualitative and quantitative results. The major feature of wavelet transformation is the...
This panel paper presents research activities related to modeling portability between electromagnetic transients simulation programs. Although modern computer programs are provided with sophisticated graphical user interfaces, each program has its own modeling interface and model development methods. There are no portability or interoperability standards between applications of the same type. This...
To have an accurate simulation of capacitor voltage transformer (CVT) the proper modeling is required. This paper presents and implements a comprehensive model of CVT in the PGTRP software. The transient behavior of CVT is then investigated under different faults. Finally, the effects of CVT transients on distance relays performance is studied using extensive simulation.
In this paper, a Kalman filtering based approach is proposed to measure the light flicker of the electricity transmission systems. Analytical expressions of the instantaneous light flicker sensation are obtained beginning from a voltage waveform and these expressions are used to obtain a flicker estimation method based on the IEC (International Electrotechnical Commission) flickermeter. In the proposed...
This paper presents a support vector regression machine (SVRM) to predict the energy margin (EM) of power systems subjected to severe disturbances. The nonlinear relationship between the pre-fault, during-fault and post-fault power systems parameters and the degree of stability of the system under post-fault state is captured by the SVRM trained offline. Significant generators are selected by feature...
One of the most important issues on the power system course is the study of the transient power systems. However, due to the complexity of the power systems networks, for an effective instruction of this topic it is required to use a computed simulation environment to provide a complement to analytical methods. Therefore, a methodology for the modeling of power systems on the transient analysis using...
In this paper, application of SVM to classify disturbances in power quality is discussed. Power system transient can pose a serious threat to the reliability of power system apparatus and sensitive loads. There are numerous causes of power system transient namely short circuits, capacitor bank switching, switching of large inductive loads that include motors and transformers as well as lightning....
The paper presents a comparative study of three different 3D-SVM techniques for the control of flying-capacitor multi-level inverters under both balanced and unbalanced operating conditions. Simulation results show that Direct 3D-SVM is the most efficient in computational effort. Application of this scheme to a three-level FCMI is simulated using the Alternative Transients Program (ATP). Output performance...
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