Research On Substation Training And Simulation System Based On Pre-simulation Strategy

At present, substation training and simulation system has become an effective training tools to train substation stuff, among which hybrid substation simulation and training system receives much concern. Real time digital simulation is used to the primary simulation system of the simulation and training system, while real equipments is adopted to the secondary simulation system. The signals of VT voltage and CT current provided by the real time digital simulation of the primary system must real-time in order to ensure real equipments of the secondary system to be normal operation. when parameters of simulation model work stably, computing time is short, but once it suddenly change, computing time become longer so that the mass calculation will be produced.According to above problem, The primary simulation system of hybrid substation simulation and training system is studied .The following work is made in this paper.Firstly, the primary system simulation model of the substation is established by the differential method. Simulation models of the power supply, transformer, line, load and other major equipment of the substation are discussed in the paper, and also including the switches, substation equipment and line fault model.Secondly, the Polynomial Preconditioned Conjugate Gradient method (PCG) is used to the solution of the simulation model. The algorithm is mainly applied to solve linear equations formed in the primary system transient simulation. PCG is an improved method compared to the CG method. By pretreatment to the coefficient matrix, the eigenvalue of the coefficient matrix is more focused, and the convergence rate is speed up. In addition, PCG method fully takes advantage of using the CG method, which is easy to parallelize and also takes advantage of sparse features, which effectively reduces the computational.Finally, the algorithm combines a number of accelerated simulation technology to speed up the speed of simulation. In the area of simulation model, Bergeron’s circuit is used to segment the whole simulation model into the power supply ends module, substation equipment module, line module and load module. The short circuit transfer method is used to simplify the substation simulation module, which only including the transformer, feeder bus nodes and endpoints. Logical analysis is used to determine the real current of current transformer, which effectively reduces the compute nodes and the size of the simulation model, providing a good method for the simulation of substation expansion In the area of algorithm, in order to solve the mass calculation when parameters of simulation model suddenly change, a pre-simulation strategy in which the calculation model is independent from output model is proposed.