faults/fractures detection is an essential step of the full field study in hydrocarbon reservoir. definition of exact location of these structural events is a critical step to optimize location of the development wells. despite of the fast development of the geo science technology and oil industry in recent years, detection of the small geological events such as faults and fractures in some of ...

Original scientific paper In this paper, the necessity of the protective relay of the micro-grid is described as the anti-islanding protection and Low Voltage Ride Through (LVRT), and the fault characteristics of the renewable energy sources are analysed. The applicability of over-current protection, distance protection, differential protection, pilot protection, voltage protection and frequenc...

To transfer large amount of direct current power having high amplitude voltage over long distance, high voltage direct current (HVDC) transmission system is used. This system was introduced 60 year ago and now it is widely used all over the world. Some examples of HVDC systems are following; Voltage-SourcedConverter (VSC), current commutated converter (CCC) and line commutated converter (LCC) d...

Power transmission and distribution lines are the vital links that achieve the essential continuity of service of electrical power to the end users. Transmission lines connect the generating stations and load centers. As the generating stations are far away from the load centers they run over hundreds of kilometers. Hence, the chances of fault occurring in transmission lines are very high. Sinc...

Cascaded tripping of power lines due to mal-operation of zone 3 distance relays was one of the main causes of many previous blackouts worldwide. Encroachment of load into the zone 3 characteristics is one of the main cause for the maloperation of the relays. By improving the operation of zone 3 of distance relays it is possible to prevent such mal-operations so that cascaded line tripping can b...

Wireless Sensor Networks (WSN) promise researchers a powerful instrument for observing sizable phenomena with fine granularity over long periods. Since the accuracy of data is important to the whole system’s performance, detecting nodes with faulty readings is an essential issue in network management. As a complementary solution to detecting nodes with functionnal faults, this paper proposes FI...

Transmission lines are usually suspended from steel towers and provided with one or more earth wires. Therefore the earth fault resistance during flash over on the isolators is only few ohm. In the case of rare arc faults, at mid-span, or during flash over to trees, very high impedance faults may result. Depending on the setting of the zones in R-direction, a maximum of some tens of ohms can be...

This paper presents an algorithm for adaptive determination of the dead timeduring transient arcing faults and blocking automatic reclosing during permanent faults onoverhead transmission lines. The discrimination between transient and permanent faults ismade by the zero sequence voltage measured at the relay point. If the fault is recognised asan arcing one, then the third harmonic of the zero...

subalpine ecosystems are highly fragile as compared to biological andenvironmental factors. landslide is one of the ruinous upshots of this ecosystem. one of theimpressionable areas in the cause of natural factor is masoleh watershed in western alborzmt, (iran). in order to landslide hazard zonation, landslide index and frequency ratio methodbased on twelve causative factors such as slope, slop...

Subalpine ecosystems are highly fragile as compared to biological andenvironmental factors. Landslide is one of the ruinous upshots of this ecosystem. One of theimpressionable areas in the cause of natural factor is Masoleh watershed in western AlborzMt, (Iran). In order to landslide hazard zonation, landslide index and frequency ratio methodbased on twelve causative factors such as slope, slop...