A study on high-speed data acquisition system for single ended traveling wave fault location

Single ended traveling wave fault location technology has been commonly used for testing cable for years. The waveform attenuation and distortion of the reflected pulse is an inherent problem to define the arrival time and the propagation velocity of traveling wave correctly. Aim at obtaining the required information of the incident and reflected pulse waveform, a high-speed data acquisition system is designed based on the technology of random equivalent sampling (RES). And the problem of data storage and communication caused by high sampling rate is solved. The highspeed data acquisition system consists of fine time interval measurement module with 65ps resolution which is the key technology of RES, relatively low-speed A/D converter, Field Programmable Gate Array (FPGA), high-speed Synchronous Dual-Port RAM buffering storage and high performance programmable digital signal processors (DSP). The data acquisition and storing of the system is realized with FPGA and DSP as the core. The system promises 15.4GHz equivalent sampling rates with 125MHz real-time sampling rate. Experiment proved that the high-speed data acquisition system is stable and accurate.