The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Electric power supply installations must ensure a permanent power feed to the train traffic security installations. Any damage to the power feed components lead to delays in train traffic. This work proposed a modern computer-based diagnosis method based on diagnosis charts, both created by the authors. Running the hereby proposed software package and following its indications, the failure cause can...
In practice, vector control methods are widely used offering the possibility to reach high performance. Certain application areas need optimum control in at limit operating conditions, as, operation at maximum torque. The paper presents how through the proposed control scheme at the output of the flux and the voltage controllers, provide direct the frequency and voltage values for an asynchronous...
This work presents the limits of mathematical models of wind turbines. At a wind turbine, WT, in the region of negative powers, Pwt, usual mathematical models are no longer valid, the errors being unacceptably high, the obtained values are much different from real values. In the area of positive power, the mathematical models are valid and approach to the real power characteristics. These considerations...
Practical installations of illuminance systems use Light Emitting Diodes (LED) more and more. In most of the cases, tests in the field have shown that the details listed on the lights' technical specifications differ from the field values. The present study has been done on 7 W light sources with a 700 lm nominal light flux. We use statistical methods on multiple measurements sets on LEDs to determine...
This article presents a method for the computerized diagnosis of entry lighting signals in a CFR1 railway station. The railway station is controlled by a Electrodynamic Centralized type 4 block-and-interlocking installation. The work presented here deals with interrupted glowing wire signals of the red light and with the inability to command the call signal. The proposed method substantially shortens...
The entry signal of a Romanian railway station is an installation that allows or forbids the entry of a train in the station. Together with other, interconnected installation, the entry signal insures the railroad traffic safety. Any defect to the signal cause train delays, signal malfunctions may cause railroad traffic events. The diagnosis method proposed in this work comes to the aid of railroad...
Continuous development of urban areas and extending industrial zones have lately generated an accentuated trend in the transition from aerial electrical lines to cable lines. At the same time with this transition, a number of problems occurred connected to the normal operation of the power cables and their use in powering domestic and industrial electric consumers. This work discusses actual issues...
This paper presents a control method for a wind turbine with a synchronous generator with permanent magnet (SGPM), to achieve optimal function in the optimal energy field at variable wind speed. The wind speed and the angular speed of the SGPM impose the value of the generator load in the optimal energy area. Based on energy balances, done with speed and power measurements, the generator load is determined...
The Automatic Block Signal installations (ABS) is a system of powering and receiving circuits that ensure train traffic command, control, and signals between two consecutive train stations. The circuits are usually electronically or electrodynamically synchronized. Because the distance between two stations is at least 4 kilometers, any failure to these installations cause long traffic delays, especially...
In train traffic, traffic security installations failure recovery is time consuming, causing time delays the the railroad traffic. Automatic Block Signal Installations (ABS) are on type of installations that ensure railroad traffic security. To decrease the failure diagnosis and remedy times for ABS Installations in cases where the installations do not regularly invert, we defined a set of diagnosis...
We present in this paper a software module for the diagnosis of Automatic Bloc Signaling installation failures in situations where the train open line figures as blocked, although it is, in reality, free. The software module created by us, LCOBla, is designed for the use of maintenance staff specialized in Signals, Centralizations, Blocking (SCB) at the Romanian Railroad Company (CFR). LCOBla allows...
This work presents a method to determine rotor oscillations during a three-phased sudden short-circuit test of a synchronous generator. To our best current knowledge, no such similar method is yet published in the technical literature. During the periodic and non-periodic component separation of the three phase currents, it was found that the time difference between the currents' extreme values, for...
This paper analyzes some transient processes specific to high voltage electric networks. There are followed especially the electric stresses in disconnecting shunt reactors. Analytical and numerical determinations are taken into account. The simulations confirm the analytical conclusions.
We present in this work the use of the CONMac software, named so by authors, for the switch electromechanics failure diagnosis, when the failure cause is absence of electric control. The software is created in response to the need of quick and reliable methods for failure diagnosis as well as a way to safely operate remedies to the switch electromechanics. The software can be used by the traffic security...
In this paper the authors aim to make a comparative analysis of performance for the same synchronous generator, resulting from the calculations of classical designing and the calculations of optimal designing. The analysis is done for different values of the air gap magnetic induction, Bδ, within the range indicated in the design manuals. Both of designing methods using the MathCad software. The optimal...
This paper presents a comparison between the stationary and dynamic parameters of a synchronous generator depending on the air gap magnetic induction. To perform this comparative analysis it was necessary to classical designing and optimal designing of the synchronous generator. The classical designing followed the steps indicated in specialty literature, and to reduce the designing time and for more...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.