Efficiency Optimization And Design Of Extended Interaction Device

Extended Interaction Device(EID)is a type of vacuum electronic device that combines the advantages of klystron and traveling wave tube.It has become an important high-power source device in the millimeter-wave to terahertz band.How to obtain high frequency,wide bandwidth,high power and high efficiency has always been the research focus of high frequency microwave devices,but the optimal value between the various objectives of the Extended Interaction Device will be restricted by objective conditions.This paper based on the one-dimensional nonlinear self-consistent theory,taking the W-band Extended Interaction Oscillator(EIO)as an example,considering of output power,efficiency,bandwidth and number of periods,the simulation analysis and optimization design have been discussed,mainly completed the following work:(1)Based on the electronic disk beam-wave interaction equation and the basic principle of energy conservation,combined with the cold measurement parameters of the extended interaction oscillator,a one-dimensional self-consistent nonlinear theoretical model is obtained,and the W-band and 7-gap oscillator are used as examples to calculate and simulate.The effects of the structural parameters and operating parameters of the oscillator on its output power,electron conversion efficiency and start-up time are discussed.(2)Based on Non-dominated Sorting Genetic Algorithms ?(NSGA-?),the Extended Interaction Oscillator optimization problem is equivalent to multi-objective optimization problem,the decision vector and solution vector are completed.Combining the one-dimensional nonlinear program with the NSGA-? algorithm,the automatic optimization program of the output performance of the Extended Interaction Oscillator is obtained.The optimization results and the parameter distribution rules under different periodic parameters and objectives are analyzed.The global optimization algorithm for dealing with multi-dimensional complex problems of extended oscillators is obtained,which effectively solves the problem of multiple target embedding of output power,efficiency and bandwidth.(3)According to the global optimization program,the working parameters and structural parameters of 6-gap Extended Interaction Oscillator structure are obtained and the output power is 2065W,conversion efficiency is 25.2%.The optimized structure is modeled by CST,and the PIC simulation is used to verify the accuracy of one-dimensional program.Finally,a high-frequency structure with output power of 1893W and conversion efficiency of 22.7%is obtained,which verifies the feasibility of global optimization of extended interaction oscillator.