Research On Transient And Power Flow Calculation Interface Of Four Winding Induction Filtering Transformer In PSASP

In order to suppress a great amount of harmonic generated by 220 k V substations and meet actual demand of compensating the reactive power in power systems,the four winding induction filtering transformer and its LC tuning device which can take advantage of the principle of ampere-balance between four windings at specific subharmonic frequencies are used to control harmonic pollution and improve power factor.What is more,when the novel transformer is put into operation in the substation,it cannot be directly used for simulation such as transient stability,power flow calculation in PSASP because its structure is different from the three winding transformer,which is not conducive to the promotion and application of the novel transformer in various fields.This paper focuses on how to connect the novel transformer with the highly professional power system simulation software PSASP and finally realize the important problem of transient and power flow calculation simulation.This article mainly describes the research content from the followi ng aspects.Firstly,this paper describes the working principle of the novel transformer to eliminate the harmonic flux of the internal iron core,and analyzes the necessary condition for implementing the induction filtering technology.On this basis,the mathematical model is derived through a series of basic theories,and the equivalent circuit of the novel transformer is established after the polygon circuit of a multi-winding transformer is simplified.And the mathematical expressions are used to describe the operating characteristics and two performance indexes of the novel transformer in the condition of stable operation,and then the inductive filtering technology is realized from its special design of the winding arrangement and parameters,impedance values and parameters of the LC tuning device.Simulation results analysis the filtering effect is significantly improved after inputing of the novel transformer.On the basis of knowledge systems such as the mathematical model of the novel transformer,the equivalent model that can reflect its external characteristics is successfully built in the MATLAB/Simulink environment.The configuration file and arguments are set according to the requirements of the co-simulation,and then the code is automatically generated by the Code Generation function.Then the main part of the system is built in the transient stability module of PSASP.The co-simulation technology of the PSASP and MATLAB is realized by the calling function of PSASP external MATLAB model and the setting of transient stability parall el computing related data,in the meantime,the correctness of the equivalent model of the novel transformer is verified.Finally,this paper introduces the basic concepts,principles and programming process of PSASP/UPI environment.According to these requirements,the power flow program of the novel transformer is compiled by VC6.0 software platform,and then the user program of the novel transformer is called in the PSASP power flow calculation function to realize the power flow calculation.the simulation results verify that the PSASP can be correctly connected with the novel transformer through the interface technology.At the same time,it shows the feasibility of the user program interface technology and the openness of the software.