The synchronization method based on the sound and magnetic makes power cable precise positioning more intuitive in this paper,which based on the pre-positioning of the cable fault an accurate fault location method.First the pulse generator discharges pulse applied to the cable, the fault point will release the sound signal and an electromagnetic signal. But the electromagnetic signal propagation speeds approaching the speed of light instantaneously reaches the point of failure.when the electromagnetic signal is detected , the microcontroller timer T1 is informed. T1 starts counting until up to the sound signal is detected. the LCD will display the counting result, and along the cable to we will find the minimum point of the time value ,which is the location of the fault point.

In this paper, A location system for single phase grounded fault in distribution network is proposed and it is based on the phase of zero-sequence current. The system is composed of central station and nodes installed on the power line, and their functions are illustrated in this paper. The principle of the method is shown and experiments are carried out. The results show that the feasibility of the method. The advantage of this method is it’s short time to detect. The method is Applicable to detect the faulty segment for neutral point non-grounded system with grounded resistance less than 1kΩ.

This article will Wave Mesh wireless ad-hoc network technology is applied to urban LED street lamp management system,with the single chip microcomputer 80C51F310 as the core,using real-time sensor testing environment brightness, and according to the brightness level of brightness, the LED street light illumination automatic adjustment;Aiming at the condition of the midnight staff less activity,using pyroelectric infrared human detection to control the brightness of the street lamp, the experimental data proved that energy saving effect is remarkable.The system safe and reliable, low cost,It has the advantages of single lamp remote monitoring,automatic dimming,electric energy measurement,alarm,fault diagnosis and fault location,etc.