Characteristics analysis and detection of AC arc fault in SSPC based on wavelet transform

Solid state power controller (SSPC) is the key component of advanced aircraft power distribution system and is adopted to control and protect the transmission lines intelligently. In addition to the common faults such as the overcurrent and short circuit, arc faults will also damage the transmission lines in aviation electrical system. In order to improve the overall safety of the aircraft, it is necessary to study the SSPC with function of arc fault detection_(AFD). In this paper, the discharge characteristics and classification of arc faults are introduced first. Then, the research status of AC AFD methods are summarized; meanwhile, this paper analyses those methods advantages and disadvantages, and a new method for arc fault detection based on arc fault difference signal analysis and wavelet transform is proposed. For series arc characteristics described, experimental Test bed is built to obtain the data of aviation AC series arc fault under two different loads. The fundamental waves of the collected current signals are removed, then the obtained difference signal is analyzed by the stationary wavelet transform in matlab, and then the modulus maxima of a layer of detail waveform are selected as the feature for detection. The experimental results show that this method can improve the accuracy of fault arc detection.