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With the increasing application of electrical and power electronic equipments, there are more and more power quality problems due to the special loads applied to the power grid even the whole power system. A definition for the Pulsed Power Load is advanced, and 3 types of circuit structure model of pulsed power load are devised with the analysis of its fundamental, among which the differences of modeling...
Due to the continuous increases of the tonnage and consequently of the power required on board, low voltage systems are being replaced by High Voltage (HV) distribution systems. The advantages are a partial reduction in fault currents values and cable weights, with consequential benefit for overall weight and dimensions. The 2010 Manila Amendments to the Standards of Training, Certification and Watchkeeping...
This paper presents the design and simulation of a simple wind farm consisting of three identical airborne wind energy systems. The novel concept of airborne wind energy (AWE) is briefly introduced. The focus of the paper is on the modelling of an operational method that provides a continuous power supply from a cluster of AWE systems whose individual operation delivers a non-continuous, periodic...
This paper presents a micro-grid simulator tool useful for implementing and testing multi-agent controllers (SGridSim). As a common engineering practice it is important to have a tool that simplifies the modeling of the salient features of a desired system. In electric micro-grids, these salient features are the voltage and power distributions within the micro-grid. Current simplified electric power...
In order to facilitate exchanging and sharing data between the domestic and international main tools for power system electromechanical transient analysis, this paper analyzes and compares the common mathematical models for transient stability including synchronous generator, excitation system, turbine and governor, load and even DC transmission system in PSD-BPA and PSS/E. Several typical problems...
Under frequency load shedding has been widely used to restore the power system frequency following a severe generation demand unbalance due to a disturbance. If system frequency is not counteracted properly system will be led to major blackouts. This frequency decline may be corrected by shedding certain amount of load so that system is back to stable state. This paper reports a case study on Sri...
In software testing, most attention is given to verify the functionality of produced software. However, the quality of services (such as time to response or amount of produced data) is also important, especially in world of mobile or embedded devices. These properties are often estimated by using models of components, instead of testing the components from real applications. We have developed a simulation-based,...
In this paper, the APF and zig-zag transformers technology are applied to the design of generator wave filter, article focus on APF harmonic detection method, which is based on p-q algorithm. At the same time, According to zero sequence of harmonic problems of power transmission and distribution system, zig-zag transformers technology is adopted to suppress harmonic zero sequence, this paper also...
Most studies aimed at designing and optimizing optical networks, involve substantial software development. The software tools resulting from each project are varied but generally have parts in common. Regrouping these overlapping parts in a single framework can be valuable and enable the efficient usage of developed features for new networks design and performance evaluation. In this paper, we present...
This article presents a modular approach to generate the interleaved carriers of a parallel converters. Compared with previous solutions requiring accurate analog computations, a straightforward implementation of the generator is proposed here. By using only comparators and logical gates dedicated to the tuning of the carrier phase, a correct interleaving of the carriers is obtained in steady-state...
We propose in this paper a new hardware architecture for implementing the hyperchaotic Lorenz generator using FPGA technology. The goal is to design a new complex chaotic system which can be used as an unidentifiable key generator in embedded cryptosystems. The proposed architecture provides good performances in terms of throughput and resources cost required for highly secure communications between...
In this paper, a frequency control method is introduced for wind-diesel hybrid system by using a sliding mode controller and a Super-Capacitor energy storage system to reduce frequency deviations. By means of the proposed method, output power control of WTG system considering the conditions of power utilities and maximizing energy capture are achieved. The proposed method is compared with the conventional...
A new current-mode triangular/square wave generator based on MO-CFTAs (Multiple output current follower transconductance amplifiers) is presented in this paper. The circuit description is very simple, its construction consists of 2 MO-CFTAs and 1 grounded capacitor without any external resistor. The output frequency and triangular/square wave amplitudes can be electronically/independently tuned via...
Electrostatic energy harvesters powered by ambient motion and integrated at the microscale are an attractive replacement for batteries in small, low-power electronic devices. This paper contains model and design considerations for electrostatic generators based on mechanically-variable capacitors. The performance of single-stage and multistage microgenerators are compared. The main design trade-offs...
Several methods that can be used to verify effectiveness of startup circuits in eliminating known stable Trojan operating states will be discussed. It will be shown that some widely used approaches do not guarantee Trojan states have been removed. Some of the methods introduced appear to be more practical to work with than others. These methods can also be used to identify the presence of unknown...
In the encoding of Luby transform (LT) codes, information bits (variable nodes) are randomly connected to the check nodes. Although the check-node degrees have been optimized for error-rate performance, the arbitrary connections in the code graph cannot guarantee efficient propagation of the channel information (intrinsic messages), and may slow down the convergence speed of the iterative decoding...
Government incentives to use alternative renewable sources of energy have caused an increase in requests for connections of small generators in distribution networks. The presence of this distributed generation enables its islanded operation, forming microgrids, when there are contingencies in the main grid. Taking into account the Brazilian regulating procedures for distribution networks (PRODIST),...
This paper proposes a robust control of double-fed induction generator of wind turbine to optimize its production: that means the energy quality and efficiency. The proposed control reposes in the sliding mode control using a multimodel approach which contributes on the minimization of the static error and the chattering phenomenon. This new approach is called sliding mode multimodel control (SMMC)...
In this paper we propose a multi-agent approach for modeling an industrial system (boiler). A Multi-Agent System (MAS) are used in order to modeling a complex system which requires the consideration of its several parts. A system which can often be tackled from different angles. We have identified the set of problems to solve, searched and find convenient multi agent models for their resolution. Then,...
This paper addresses the problem of generating non-overlapping clock phases for switched capacitor circuits at more than 1 GHz clock frequency. A simple clock phase generator providing two non-overlapping phases with low values of RMS period jitter, RMS jitter of phases' widths and phase shift of 180 degrees is proposed. The circuit relies on a back-to-back inverter structure. Simulation results over...
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