Abstract
With the rapid development of the national economy, our national power industry also has been developing fast. The larger the size of the grid, the more complex and advanced the power distribution network, the larger the application of power cable, the more the power cable fault. The gradually improvement of the voltage classification of transmission line and the transmission capacity leads to greater influence and loss to the social and economic life caused by transmission line fault. Consequently, how to detect the point of fault as soon as possible, especially how to identify exactly and quickly repair the cable fault, is a rather difficult task for the operation maintenance personnel of power supply. At present, the railway protection is approaching into the microcomputer protection era, while wavelet transform, as the innovative and the most effective mathematical analysis tool, has been widely applied in the power system.
This thesis is adopting the wavelet transform fast algorithm to analyze and judge the fault signal of power system. The emulation results show that this formula can judge and locate the fault precisely and timely, which conforms to the requirements of real-time project. Compare with traditional methods, this method uses the band-pass filter qualification of the wavelet, and decreases the signal loss, simplifies electrical circuit of detecting hardware system. This method is easy to accomplish and boasts a great effect of signal analysis.
Keywords:wavelet analysis、 power cables、fault waveform、the waveform detection