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.
In this paper, a new pulse separation technique based on fuzzy logic algorithm is proposed. An equivalent Time-Frequency diagram (TF map) is obtained from the feature extraction and clustering of both PD pulse signal and ambient noise signal. Since different kinds of PD types derived from different PD sources, they will form specific clusters in the TF map. It provides a possibility to classify the...
The arc energy has an important influence on the breaking capacity of switches. Based on the theory of magneto-hydrodynamics, a simplified two-dimensional dynamic arc model of switch is established and the variation law of arc temperature, current and arc shape are analyzed under the conditions of different breaking velocity and load characteristics. At the same time, the arc voltage, arc current...
Based on magneto-hydrodynamics (MHD) theory, an air arc model is set up for the contacts and arc inducing plate at chamber inlet of a certain type of DC contactor and the dynamic behavior of the arc is simulated. The variation laws of arc length and the main conductive area migrating from moving contact to arc inducing plate were studied quantitatively under the influence of breaking speed and the...
A rotary interruption technology is expected to significantly promote the breaking performance of high voltage switchgear. When the technology is introduced into a fault current interruption, arc plasma is driven to mitigate the erosion pattern of contact surface. However, there still remains little understanding on the arcing behaviors between a pair of rotating electrodes. In this paper, it presents...
Research on the problem of partial discharge after spraying zinc that has important significance for the insulation analysis and improved of solid-insulated ring main units. In this paper research object is 12kV solid-insulated ring main units' insulation cylinder, finite element analysis method is used, in the view of electric field concentration on the end of line insulation sleeve when the surface...
Using finite element simulation method to carry a comparative analysis of the repulsion mechanism and permanent magnetic mechanism, come to the conclusion that the repulsion mechanism has the advantage of rapidity;Aiming at the problem of high speed easy to cause instability, presenting a design of adding coil and repulsion chassis on the basis of the original repulsion mechanism, and optimizing the...
In order to improve the prediction accuracy of phase controlled switching operation time, restrain overvoltage and inrush current when the circuit breaker switched on, this paper establishs BP network prediction model based on voltage and ambient temperature as the main input parameters, and weights the uncertainty influence factors such as aging and wear. In order to improve the accuracy of prediction...
The small fault samples and single characteristic parameters in vacuum circuit breakers (VCBs) would lower the accuracy and reliability of mechanical fault diagnosis. In this paper, the problem has been solved with applying a fault diagnosis method based on particle swarm optimization (PSO) and least square support vector machine (LSSVM). By analyzing the close coil current (CC) of VCB, the eigenvalues...
In view of the requirement of high reliability and small disturbance in the condition of high-voltage (HV) vacuum circuit breaker (VCB), this paper puts forward a method of fault diagnosis based on online monitoring of vibration and acoustic signal. The research object is the 12kV indoor high-voltage vacuum circuit breakers and the system of fault diagnosis of the research object is built. This method...
This paper presents a power supply used in switching DC / DC converter new current sampling circuit, the main power drop by detecting switch series inductor current is sampled on to replace traditional detection sampling resistor voltage power on the bus on the drop method. Methods currently required less resistance, more efficient, low power consumption, and the drop of the inductor current changes...
For improving reliable operation of switchgear in power system, an approach for on-line monitoring the insulation characteristic and bus-bar temperature rising of the switchgear is proposed in this paper. Through comparing several existing temperature measurement methods for monitoring temperature rising elevation at bus-bas, a new design of temperature monitoring method is proposed. It adopts quick-magnetic...
Detection device of circuit breaker (CB) mechanical characteristic is established in the paper, which takes TMS320F2812 as a core, and makes a logic extension. The necessary signal is collected, stored, and transmitted to position machine upper memory block through CAN bus. The signal is analyzed and disposed, and the experimental data is transported to remote monitoring machine, thus the date is...
The nozzle structure of circuit breaker has a direct influence on the flow of blowing arc gas. Based on equation of N-S, the flow field and the electric field in the arc chamber which has different nozzle throat diameters without load are calculated and simulated in this thesis. The influences on the flow of blowing arc gas and the characteristics of dielectric recovery in SF6 circuit breaker with...
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.