Reliability Analysis Of Power Electronic Circuits Base On Complex Network

The importance of the power electronic circuits has become much apparent with theywidely used in various fields of the national economy, and the requirements on their stabilityand reliability has also increased. Therefore, the reliability research is necessary for powerelectronic circuits. In recent years, complex network theory has been widely used in the friendrelationships, the virus spread networks, transportation networks, scientific citation networks,financial networks, electricity networks and so on, it’s an effective research tool of thereliability for kinds of actual networks from the angle of the system. Studies have shown thatthe power electronic circuits have the complex network characteristics, so the complexnetwork theory can be also used to analyze the reliability of power electronic circuits.The network models of power electronic circuits are set up and the network characteristicparameters are calculated in this paper, and the importance of each element in the powerelectronic circuits is quantified, the key elements of power electronic circuits are found out.Then, base on the reliability characteristics of power electronic circuits, some measures forenhancing the circuit reliability can be got.In this paper, the following several aspects are studied:1. The unweighted network models under normal and different fault conditions of powerelectronic circuits are built, the centrality parameters of each node in the network modelsare calculated, and the key elements of power electronic circuits are found. Then, byquantifying the influence of each element toward the network efficiency in theunweighted network model according to assuming each element fault, the correctness ofthe judgment about the key elements is confirmed.2. The reliability difference are further considered in different power electronic components,the average failure rate of the two components at both ends of each electrical connectionline in the circuits is used for the edge weight, and the weighted network models of powerelectronic circuits are built based on the unweighted network model, the structurecharacteristics and the reliability of each component are reflected together in thismodeling method.3. The network efficiency of the weighted network models are calculated when the failurerate of each component is changing, the weak points in power electronic circuits arefound, and it is proved that the reliability of power electronic circuits not only contactwith the failure rate of the elements, but also relate with the position of the elements inthe circuits. 4. Based on the relevant conclusions obtained by analyzing the reliability of powerelectronic circuits, some design methods for enhancing the circuit reliability can beproposed and proved. In the last, the optimization design strategy of power electroniccircuits are discussed briefly when the reliability and the cost of the circuits areconsidered at the same time.