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Electric drive system with Insulated gate bipolar transistor (IGBT) power device is widely used in Electric vehicle (EV), which consists of inverter, cables and Permanent magnet synchronous motor (PMSM). Due to the fast switching in di/dtand dv/dtof IGBT device, the system produces serious radiated Electromagnetic interference (EMI) through the interconnection cables. Thus, modeling of EMI source, propagation path and load PMSM is the key to accurately evaluate the system's radiation level. In addition, the system's radiated EMI involves the integrated calculation of circuit, cable and electromagnetic field, which cannot be solved by using a single circuit or electromagnetic calculation method. Therefore, this paper develops an effective field‐linecircuit coupling based method to investigate the radiated EMI problems for IGBT‐PMSM drive system, which is validated by experimental measurement. Besides, the impact of power cable parameters on radiated EMI is discussed. The proposed approach has guiding significance for electromagnetic compatibility design of EV.

The current methods of detecting flight conflicts are difficult to grasp the overall conflict situation in the air, which is not conducive to the controllers to make accurate judgment on different conflict situations. In this paper, a method to identify key nodes of flight conflict based on complex network theory is proposed. Firstly, a conflict situation network model was built based on the ACAS protection area model. Then node degree centrality, closeness centrality and PageRank were used to evaluate the comprehensive importance of all nodes in the conflict situation network by AHP method. And we can find out the key conflict locations and conflict aircrafts based on the evaluation results of the index. The simulation results show that the model can effectively identify the key conflict aircrafts and positions in the airspace. And It can help controllers fully grasp the air security situation by classifing the air conflict situation levels.