2:00 pm on May 25, 2021，By Graduate School of Shandong University、Sponsored by the Postgraduate Affairs Department of the Party Committee，The 55th (total 1044th) "Jixiafeng" postgraduate academic forum hosted by the School of Electrical Engineering was held in the lecture hall on the fourth floor of the Electric Power Building on Qianfoshan Campus。This forum invites Professor Yin Yi, Vice Dean of the School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University，The topic of the lecture is "Characterization of charge transport in solid media、Simulation and Engineering Applications”。This forum is hosted by Professor Li Qingquan。

Lecture begins,Yin YiProfessor’s research significance on charge transport in solid media、Experimental characterization technology of charge transport in solid media、Numerical simulation of charge transport in solid media、Engineering applications of charge transport in solid media, current problems and prospects are expanded into five aspects，Systematically introduced the research results of their team。Yin YiProfessor first passed through the diversification of voltage waveforms under working conditions faced by electrical equipment、Higher workplace strength、Tests and challenges such as obvious local electric field concentration lead to the necessity of studying solid insulation issues under high field strength，Because there are a large number of solid media in widely used power electronic devices，And the anomalies of solid dielectric charge under high field strength，The study of charge transport in solid media is of great significance。Continue，Yin YiThe professor introduced several characterization techniques of space charge，Respectively, combined with conductance characterization、Periodic electric field and full size cable，And introduced their respective characteristics in detail，Also，Yin YiThe professor also introduced the traditional method of experiments and the characterization method of the dielectric strength of solid dielectric embedded in electrodes，And the relationship between solid dielectric resistance dendrites and partial discharge consistency、Characterization of temperature and electric field on field strength and conductivity of solid media。Continue，Yin YiProfessor’s Special Problem Modeling Through High Field Charge Transport——The difficulty lies in the physical process under "high field" tells the meaning and application of simulation，And introduced in detailS Le RoyThe traditional bipolar carrier model proposed by the research team，As well as the physical process and simulation of charge transport in high field modeling and two-dimensional structure segmentation algorithm。Continue，Yin YiThe professor gave an example of the engineering application of charge transport in solid media，One is the simulation of DC prevoltage short-circuit electrical tree behavior，Because the experimental phenomenon cannot be quantitatively explained，The other is space charge dynamic simulation of high-voltage power electronic module packaging insulation，Cannot be directly measured due to small scale，The other one is the space charge under the alternating electric field of oil-paper insulation。final，Yin YiProfessor mentioned，Current research on charge transport in solid media，Acquisition of simulation parameters、The improvement of physical processes and the simulation of long-term dielectric behavior still need to be improved。

Question session，Students and teachers present asked questions on different issues，There are different electrode models such as needle plates、Problems with making needle balls, etc.，There are improved methods for breakdown experiments, etc.，Yin YiThe professor explains one by one，Professor Li Qingquan also put forward his own opinions on the lecture content。This issueThe "Jixiafeng" postgraduate academic forum ended successfully with warm applause from teachers and students。

Speaker’s introduction:

Yin Yi, male,Born in October 1972，Jiangsu Jintan people。Professor，Doctoral Supervisor，Vice Dean, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University。Main research areas include: (1) Dielectric physics theory and engineering application of polymer nanocomposite media；(2) Key technologies and engineering applications of ultra-high voltage flexible DC cables；(3) Solid medium carrier transport model and space charge characterization technology；(4) Power equipment insulation status assessment technology based on generalized relaxation theory and multi-technical correlation analysis。As the person in charge，Undertaken key projects of the National Natural Science Foundation、Special Project on Basic Scientific Instruments、National 863 project and national key R&D projects, etc.。Published more than 150 papers in domestic and foreign academic journals and conferences。