Research On SHEPWM Method Of Multilevel Inverter Based On Imperialist Competitive Algorithm

Multi-level inverters are widely used in high-power applications because of their high voltage level and low electromagnetic interference.SHEPWM technology has the advantages of low switching frequency and good waveform quality.It is widely used in high-voltage and large-capacity applications.This paper takes Seven-level cascaded H-bridge inverters as the research object,and conducts SHEPWM research.The specific contents are as follows:This paper introduces the common topology and control method of multi-level inverters,and analyses their characteristics.Taking two-level inverters as an example,the working principle of SHEPWM is explained.The two-level SHEPWM equations are established and solved.The trajectory diagrams of three and five switching angles are drawn.The simulation results show that the specified harmonics are eliminated.The shortcomings of existing algorithms such as numerical algorithm and genetic algorithm in solving SHEPWM equations are analyzed.In view of the shortcomings of traditional algorithms for solving SHEPWM equations,this paper proposes an imperial competition algorithm for solving SHEPWM equations.Compared with traditional algorithms,imperial competition algorithm does not need initial values,has higher accuracy and convergence speed,less evolutionary algebra and is not easy to premature.The SHEPWM non-linear transcendental equations of three-level and cascade H-bridge Seven-level are deduced and established.The trajectory diagrams of three and five switching angles of three and Seven-level are solved by Empire Competition algorithm.The simulation results show that the solution of Empire Competition algorithm is feasible.The calculation results of imperial competition algorithm are processed,and the performance of imperial competition algorithm and genetic algorithm are compared in detail.The results show that imperial competition algorithm has higher accuracy and convergence probability,and is not easy to premature.The experimental platform of cascaded H-bridge Seven-level inverters is built to verify the switching angle of the imperial competition algorithm.The results show that the imperial competition algorithm is correct.The paper has 37 figures,13 tables and 69 references.