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Even though the concept of Demand Response (DR) is not really widespread across Romania yet, the Technical University of Cluj-Napoca (TUCN) is currently implementing a pilot project in its own buildings within the Horizon 2020 Project named DR-BoB (project no. 696114/2016). The main purpose of this pilot project is to develop an energy monitoring and targeting system, along with a DR program in load...
The paper deals with the design of an electric locomotive drive system used in electric railway transportation. The drive system consists of an induction motor and a voltage source inverter. A dedicated induction motor design algorithm is developed, in order to improve the motor efficiency. The design of the induction motor was realized with MathCAD and validated with Matlab Simulink. In the second...
A new formula for the hysteresis losses prediction at higher magnetic fields is proposed. Its efficiency is tested both for sinusoidal and non-sinusoidal waveforms, applied for non-oriented magnetic FeSi sheets of various sorts, which are used for electrical machine cores. The model parameters are identified starting for laboratory measurements made by a standardized single sheet tester (SST). The...
Distribution networks are increasingly hosting embedded generators, most of them converting renewable energy primary sources. These units are usually interfaced with the main network by means of static power converters. Grid codes have recently introduced stabilizing functions to engage distributed plants in supporting the main system stability during network events and consequent voltage/frequency...
Switched networks modelling lead very often to discontinuities of circuit's variables corresponding to switching time moments. This phenomenon is said to have inconsistent initial conditions (IIC). The IIC problem appears only for ideal switches in ideal circuits when, after switching, the circuit contains excess elements. As a consequence, Dirac delta functions and their derivatives can occur in...
In this article we'll tackle the control of multi-motors electric drives with high dynamic, with rapid changes in torque and speed, with flexible coupling of motors, where the control strategy is FOC (Field Oriented Control) for each drives and the distributed control in local network using the CanOpen protocol. In the surface mining industry, from which the electric drive application for this article...
This paper presents a comprehensive survey of the energy harvesting concept in the current social and technological context, with the intent to draw attention to linear generators, in different topologies, as competitive candidates in green energy conversion microsystems. The emerging technologies of energy scavenging are discussed, examining both the environmental sources and a selection of applications...
A brief review of technical solutions for the implementation of controlled "flexible" connection of asynchronously operating power systems was made. Transmission of active power between power systems with the same nominal frequencies, linked via phase-rotating transformer is examined. The device is based on hexagonal scheme, which provides symmetrical 12-phase output system of voltages,...
World of industry in this moment doesn't offer possibility to have unlimited time for maintenance. When a breakage it is happen, in a limited time you need to solve the problems. In this article we are proposing a solution for a good management of accidental maintenance. Our solution is a little module that can be interchanged in a system when the breakage of this appear. The module that we propose...
This paper proposes a novel method to estimate the influence of domestic consumers on power quality, namely harmonic pollution, using fuzzy logic. Comparing the conventional measurement approach, the proposed fuzzy logic method is simpler and time saving. The fuzzy logic system used to quantify the impact on harmonic distortion, contains several modules: the fuzzifier, database, base rule and defuzzifier...
The paper is focused on the simulation, realization and testing of a low current RC passive filters. The analysis relies on low pass and high pass first order passive filters. Staring from these filters other two RC circuits can be achieved: band pass and band stop filters. Based on the results yielded by the design and respectively by simulation, an integrated experimental platform was realized....
The development of IPC technology provides additional opportunities to improve the controllability of widely branched heterogeneous electric networks. The objective of this paper is to present innovative variant of decoupling interconnector that is capable in bidirectional control of active and reactive power flows throughout operating transmissions. A high degree of controllability in this case is...
The increased penetration of RES requires the development of advanced control techniques that can work accurately with improved performance and less computational resources under unbalanced and harmonically distorted grid conditions. The paper sets out with a benchmarking study of two existing current control techniques developed for compensating the harmonics and gird voltage unbalance. The techniques...
The paper presents the results of a new statistical based data mining approach that explores the load curves in order to detect abnormal data, the so-called outliers. The load curves characterized by their main indicators are provided from Smart Meters mounted on the power substation. The proposed method was tested using a real database with 290 substations from rural area. By outlier's elimination,...
This paper examines the effectiveness of additional reactive current injection of the inverter-based distributed energy resource to mitigate short voltage instability during extreme-low voltage ride through, by studying the steady-state voltage rise effect under different X/R ratios and the effect of normal operating setting, such as unity-power factor and under-excitation. The response to the potential...
Transformers are the most complex and costly components of the electric power grid and that is why there are monitoring systems for most operating parameters except for the winding axial clamping forces. It has been demonstrated that they vary in time as a result of stresses to which the transformer is subjected. An objective assessment of the lifetime mechanical stability can be made only by the...
In this paper we present some aspects about the design of a small permanent magnet wind generator with axial magnetic flux often used in residential wind turbine. There are presented the main steps of the magnetic and electric calculations with applications to a specific case: 0.6 kVA wind generator, and the finite elements analysis of the excitation magnetic field generated by permanent magnets....
The paper presents the energy exchange mediated by a prosumer, highlighting the measurement context for the active power and energy. It is a case study on the combined measurement uncertainty calculated for typical power system measurement chain deployed for hourly power dispatch on the Romanian Energy Market.
Wireless Sensor Networks are used widely for remote environmental monitoring, target tracking or for recording weather conditions change applied at diverse applications. They have become integral part of our lives, by giving reliable data gathering and even that the sensor node is small, lightweight and portable. As the power for each sensor node is supplied from a battery, the lifetime and residual...
This paper aims to detail and illustrate the operation of the LEMS during the grid-connected and grid-disconnected mode of the Smart Rural Grid (SRG) project. The SRG project is focused on DSO's capabilities to increase the interoperability, resilience, efficiency and robustness of the existing rural distribution network by the utilization of new Smart Grid technologies. This project is founded by...
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