Experimental Research On Series Arc Fault & Simulation Analysis On Grounding Arc Fault In Low Voltage Distribution System

The modern economy's dependence on electricity supply becomes much more and more important day after day; both low voltage distribution system size and capacity are constantly expanding, and the consequences and loss of power outages more and more serious. Therefore, the safe operation and the reliability of the power system is increasingly high demanded. Throughout the annual national fire statistics, electrical fires have been living in the fire first, and the series arc fault because of the insulation aging is one of the main causes of electrical fires. For the problem that can not effectively detect series arc fault in low-voltage distribution system, this thesis, collected loop current in residential and office building's in low voltage distribution systems with typical loads which have series arc fault by the test platform. A series arc fault identification method was proposed based on the Automatic regression model parameter; because there was no effective way to assess the single phase to ground arcing fault in low-voltage distribution system, thesis used the MATLAB software to build a model for solving the problem. Specifically as follows:The built arc generator can simulate and reflect the series arc fault in low-voltage distribution system; the series arc fault identification in residential and office buildings'low-voltage distribution system was achieved through established 3 order burg autoregressive parameter model method; through a large number of experiments, this paper proposed a reference vector fit for residential and office buildings and the experimental results also show the effectiveness of the method. It can achieve not only the series arc fault identification in linear load circuit, but also the series arc fault identification in non-linear load and its combination circuit. This method effectively solves the interference of series arc fault identification by the nonlinear loads in low voltage distribution systems.For single-phase arc short fault in low-voltage distribution system, based on the research on existing mathematical models of the arc, the paper used MATLAB/ SIMULINK simulation software to build a simulation model that could reflect single-phase arc short fault's circuit current RMS in any low-voltage distribution system. Based on the simulation model, the limitation of assessing the single-phase arc short fault by the expected metal short-circuit current was analyzed, and this paper proposed the arc fault RMS current and RMS arc voltage should be used to assess the single-phase arc short fault. Meanwhile, the arc fault protection action delay phenomenon was analyzed according to the current - time characteristics of low-voltage circuit breaker, at last it proposed the importance to take account of single-phase arc short fault circuit current calculation when design and install low-voltage distribution system.