Study Of Mine Anti?grade Trip System Based On EtherCAT Protocol

At present, China's power supply system has the prevalent characteristics of multistage and short lines per level. The multi-level feature will cause problems with protection time limit can not be met. And the characteristic of short lines each stage will lead to the polblem of quick break protection with little or zero zone. Ultimately, the two problems result in the same consequence: relay protection system go to an over-ride trip. To solve this problem, the thesis, on the basis of extensive research on EtherCAT and the actual situation of mine power system, proposes an anti-grade trip program which bases on EtherCAT protocol.Abandoning the idea to solve the problem of over-ride trip by additional devices, the program combines both the function of anti-grade trip and of monitoring system to solve the problem of over-ride trip fo mine protection system. They are combined via EtherCAT communication protocol. And the real-time feature of anti-grade trip is ensured by the real-time kernel of monitoring master station which collects the action value of each high voltage integrated protector through EtherCAT network and, according to the agreed plan, sends the corresponding instructions of action value and delay action to high voltage integrated protectors. Due to the priority of monitoring tasks is lower than that of anti-grade trip, monitoring tasks are executed in the task of anti-grade trip intervals. The solution based on EtherCAT protocol can not only solve the problem of over-ride trip without adding extra devices, but also futher improve the real-time featuer of mine monitoring system.Firstly, the thesis explores the reason of mine relay protection system override trip in detail, and proposes the anti-grade trip EtherCAT network with substations. The network is compared with the existing mine “Ethernet + RS485/CAN” double network architecture on the aspect of reliability. The real-time characteristic of system is calculated in theory, and brings out the concrete implementation plan of the system. Secondly, through the study of wavelet filtering technique and simulation, it proposes the optimal wavelet basis of both wavelet hard threshold and soft threshold de-noising method. Finally, the EtherCAT high voltage integrated protector and the software of system is designed in detail, and based on the existing labortaory equipment, the testing EtherCAT high voltage integrated protector, which consists of the Shenzhou fourth development board and AB6607 whose ESC controller is NP40, is made. The testing results of monitoring and control part show that monitoring master station can accutately and reliably detect the various values of system, including short-circuit current, remove the fault whenever there is a short circuit fault, and proves that the study of the anti-grade trip EtherCAT has a research and application value.