Research And Development Of Real-time Simulation Platform For Relay Protection

With the expansion of the scale of the power grid and the increase of the complexity of the line,it has brought huge challenges to the reliability and efficiency of the power grid operation and management.At the same time,the upgrade of relay protection devices and the application of new relay protection methods have put forward high requirements on the professional quality and practical ability of relay protection professionals.Therefore,the training of maintenance and operation staff has become more and more important.At present,power grid corporation mainly use traditional training methods such as centralized theoretical teaching and physical experimental devices for relay protection training,which is insufficient.Therefore,an efficient training equipment is urgently needed to improve the professional level and practical ability of employees.In this thesis,the development of power system simulation technology at home and abroad is analyzed,then the simulation mode,simulation characteristics functions are summarized.Based on the analysis of the relay protection simulation device,this thesis introduce the hardware-in-the-loop simulation technology into the field of relay protection training experiment.The scheme of low-cost relay protection real-time simulation experiment platform is designed,based on embedded simulation technology,which is mainly composed of a simulation machine,a real relay protection device and a host computer.Considering the switching state of the circuit breaker and asymmetrical faults,A power grid electromagnetic transient simulation model that can simulate asymmetric operation or faults is built in MATLAB language,which can fully reflect the response of the simulating power system.The Gear algorithm for rigid differential equations was written to solve the numerical oscillation problems caused by circuit breaker and faulty phase switches in grid model.The simulation model and differential algorithm written in MATLAB language are compiled into C++language,and the core part of the real-time simulation of the power grid model is realized.The hardware support of model calculation and data sampling is realized by using embedded board and FPGA.Relay protection theoretical learning and experimental operation of the host computer interface is realized by MFC framework.The function of parameter download and data monitoring from the host computer to the simulator is realized by the TCP/IP protocol.Finally,Real-time simulation of electromagnetic transient equation and excellent human-computer interaction are realized by semi-physical equipment based on ARM embedded system.The experimental results show that the simulation results of the platform are accurate and the entire semi-physical system operates reliably.The platform outputs real-time Signals of the line status through the calculation of 200μs steps.Relay protection practitioners can not only implement data collection and protection logic algorithms on the actual relay protection device,but also observe the transient change process of the simulated power grid system.The platform developed in this thesis,has been successfully applied in the Training Center of Fenghua Electric Power Corporation,and achieved excellent training results.