Computer-aided Analysis Method For Power Electronic Devices And To Achieve

With the fast development and wide application of power electronic technology, it earns much more attention to do the analysis and research on power electronic circuits by means of computer simulation. Although some of simulation software are fairly powerful efficient, due to the constraints of elements' models and the complexity of the load of power electronic devices, these software cannot accomplish all the required analysis of power electronic devices, especially the simulation on dealing with faults of power electronic devices. In order to resolve the above problems, this thesis developed a professional program for simulation analysis of power electronic devices on the basis of research on Elements Modelling Approaches and Devices Simulation Approaches.First of all, this thesis presents the modelling of different kinds of power electronic components. Moreover, it also established the electrical circuit and logical simulation models after mastering the main characteristics of each power electronic component, which was achieved by means of complete comprehension of the features of various components through the known circuit theory and modelling approaches. As the power electronic devices proposed in this thesis were studied as a whole, the high level circuit models (ideal switch model or bi-polar resistance model) are applied in the process of components' circuit modelling. The logical models of components are completed through Petri Net Theory, and the logical models of different accuracy could be established according to different simulation purposes. As the principle of decomposition step by step is applied in the process of establishing the components' logical models, which is in accordance with the idea of top-down and progressive refinement in the object-oriented program design. Therefore, the components' models constructed are described by C++ language in the simulation program.Contributed to the non-linearity, ill-posed feature and complexity of the power electronic devices, sequential analysis is used. Furthermore, modular design of the program is achieved after making sure of the overall structure of the simulation program. The general-purpose state testing module and compatible testing module, which are independent of the specific circuit architecture, are used to determine the exact moment when the states of the components in the power electronic device is changing. Although the state-equation module and output-equation module is correlative with the specific circuit structure, they could also be reconstructed as the form of module;and only the description of the state-equation and the output-equation has to be changed in different circuit structure. Due to the significance of simulation results for numerical calculating method, the features and applying range of several numerical integrating methods are discussed in this thesis, then several sorts of common arithmetic are involved in the programming for users' benefits. The accuracy and practicability of the simulation program are verified by simulation on chopper, three-phase all-controlled bridge rectifier and three-phase half-controlled bridge rectifier.