The Research Of Adaptive Transmission Line And Asynchronous Motor Protection Installed In High Voltage Switch Cabinet

The target of the research of adaptive relay protection is to settle the disadvantage in traditional relay protection and improve the performance of protection. the discussing of the dissertation is on the background of the research&develepment of adaptive transmission line and asynchronous motor protection device installed in high-voltage switch cabinet. At first,This dissertation summarizes the characteristics of adaptive protection and its development direction,and analyses the status quo and disadvantages of relay protection on transmission line and asynchronous motor in distribute power systems nowadays.then the dissertation give the project of adaptive protection in transmission line and asynchronous motor respectively. In transmission line protection,the phase differential current is regarded as the characteristic value of the adaptive protection judgement criterion.the character of phase differential current is analysed in theory and simulated by ATP-EMTP software. In asynchronous motor protection,a method is involved to judge the running state of motor,so that the set value of overcurrent quick-break can adjusts adaptively, the variate-rate of impedance at input port is regarded as the characteristic value to judge locked rotor during the starting process,in this dissertation, SIMULINK,a dynamic simulation tool in MATLAB software,is used to establish the simulation model of the asynchronous motor starting process,and simulation results verify the correctness of the judgement criterion.Also in this dissertation,a new inverse-time overcurrent protection curve is suggested to solve the precision problem of the time delay calculation in traditional inverse-time overcurrent curve. With the research of measure&protection device installed in high-voltage switch cabinet, the adaptive protection configure principles of transmission line and asynchronous motor respectively are analysed in this dissertation. also a universal hardware platform is designed installed in high-voltage switch cabinet, at last a proper structure of software for the measure&protection device is designed.