Research On Fault Waveform Inversion And Terminal Closed - Loop Detection Technology For Distribution Network

It is very important to study the influence of the fault which occurs in distribution network to the reliability of power supply system because the reliability of power distibution network has a high requirement to keep the normal running and development of the society. The fault of the distribution network system can be directly reflected in the waveform of voltage and current, so it is very important to stidy the fault waveform and establish a fault waveform gene library.This paper gives an approach to study the inversion of fault waveform in power distribution network and the terminal detection technology. First, we detect the fault in real lines by fault monitor. When the grid fails, the monitor will start the terminal fault recorder to record the fault waveform. In this paper, we explaine the operation mode of the fault monitor, and where can be installed the monitor. According to the actual topology and principle in Xiangshui County, Yunnan Province, real fault monitor was installed to catch the fault waveform. Then, a simulation model based RTDs is built. The key work is to experiment the non effective grounding and neutral point earthing system, were single grounding fault, two-phase short circuit or grounding fault and three-phase short circuit fault are simulated really. Get through the fault test, fault current and voltage waveform diagram and the A, B, C three-phase transmission line. Because RTDs is a real-time power simulation software, and build the model from the actual materials, modeling parameters are based on the actual, so the simulation waveform data and the actual age. Through simulation experiments, and summarizes the characteristics of different fault waveforms under various conditions, a fault waveform gene library is built up. Finally, In the terminal closed loop detection part, through RTDs simulation software extraction, COMTRADE format file to generate waveform data, and the file input to the relay protection tester for inversion. Relay protection testing device of D/A conversion module will automatically import the fault data as real data of voltage and current is transmitted to the terminal distribution. Only in this way can the fault occurs, the installation of feeder automation device can correct action, in order to test whether protection is useful.The inversion of fault waveform in power distribution network and the terminal detection technology is new to power distribution network. The establishment of fault waveform gene library has positive influence to the future distribution fault line selection and fault location. It is helpful to improve the distribution network fault detection.It has important significance to ensure the social production and life.