The Optimization Of Electromagnetic Railgun System

For the demand of new military revolution, the new concept kinetic energyweapons has been paid widespread attention for its excellent performance. As one ofthe kinetic energy weapon, electromagnetic(EM) railgun has the characteristic ofhigh muzzle velocity, energy available to control and good performance ofconcealment, which will be a strong part in the future. With the consideration of itscomplex launch process and testing or post-care cost, the simulation methods areutilized in the analysis and design of EM railgun. In this paper, multi-objectiveoptimization of EM railgun will be studied in order to solve the problem that themuzzle velocity and efficiency of EM railgun can’t achieve the best performancesimultaneously. With the optimization, a satisfied result of the whole system will begive by making a concession and coordination of the two objectives. Meanwhile, themodel establishment, the anylys is of performance and the singe-objectiveoptimization has been studied as well. The paper is carried out from the followingaspects：Firstly, the model of EM railgun system is established. In order to give a cleardescription of the system launch process, the system model is divided into severalsub-models including power, rail and armature-projectile. Meanwhile, the model ofEM railgun optimization is established, and the optimization indicators, variablesand the constraint are given, which makes a foundation of the simulation analys isand optimization design.Secondly, the effects of EM railgun launch Moroto to the optimizationindicators have been analyzed. In the orthogonal design, the significant order offactors and the best parameter combination are achieved via range analysis.Considering the constraints of current peak, a set of feasible solution is given by thecomprehensive evaluation, which can be used as an initial solution to a furtheroptimization design.Thirdly, the single-objective for muzzle velocity and conversion efficiency ofEM railgun has been optimized respectively. The harmony search(HS) algorithm isused as the main optimization methods, and the penalty function method iscombined to solve the process constraints problem. The result of single-objectiveoptimization can provide a reference of decision making for the multi-objective ofEM railgun optimization.Finally, two methods of multi-objective optimization are used in theoptimization design of EM railgun. First, the weighted combination method isadopted, which is the method of decision before optimization, and then the basic HS algorithm is improved, which is the method of decision after optimization. In theweighted combination method, the multi-objectives is transferred into a new singleobjective, and the new "single" objective is optimized by changing the weightingfactor. In the improved HS algorithm, the infeasible solutions are participated in theprocess of optimization to solve the constraint problems and the EM railgunperformance will be introduced to the optimization as well. With the improved HSalgorithm, a series of pareto optimal solutions are kept in parallel in the searchprocess, and the fina l solution of optimization has been selected with otherdecision-making information.