Study On Effective Domain Fusion Of Faulty Line Detection In Small Current Grounding System Based On VxWorks

In distribution power networks, because of its low-level voltage, its neutral point used to disconnect to the ground directly in order to improve its reliability. However, in recent years the distribution power networks are becoming larger and larger and the enormously use of cables in city power system, which increases the current through the grounded capacitor. These make the single-phase faulty current increase, which lead to more and more instantaneously grounding faults unable to eliminate naturally. To solve these problems, the compensating method of neutral point grounding through extinction coil is commonly used in our country.In extinction coil system, the capacitor current through fault point and the over-voltage caused by the grounding fault can be effectively decreased, which is helpful for the extinguishments of electric arc. But there are some disadvantages in this system; especially it is difficult to select the line with fault. In this system, once the problem of selecting faulted line can be solved, the method of neutral point grounding through extinction coil will be the preferred method of neutral grounding in power supply networks.In this paper, the overview of the research and development status of the small current grounded line is given. The current measurement principles, the relevant structures and reasons for their advantages as well as the disadvantages of the devices in power network are analyzed.Because single fault line selection methods only use parts of fault information for faulted line detection, its reliability poor. The thesis uses fusion technique to integrate all fault line selection method to amend the arithmetic. To improve the success ratio of lines election in resonant grounded systems, it is an importance measure to confirm the applicability of all kinds of methods, which calls validity of methods.This paper presents a new solution based on the VxWorks to realize the faulted line detection. The software design of this instrument is based on embedded real-time operation system-VxWorks. After a basic introduction of VxWorks and Tornado, the main flow chart of the system program and the blocked frame work charts of each functional subroutine are given .The hardware design for the intelligent controller is described in this thesis, and the realization plan of partial units is produced.Finally, a summary and some tentative plan on the extended research are brought forward.