Abstract:At present, the control mode of aviation engine fuel metering device is mainly indirect control based on metering valve.In order to further study the influence of different indirect control modes on the stability and dynamic characteristics of fuel metering device, the scheme of electro-hydraulic servo valve with single (double) cavity system was taken as an example.According to the physical structure and working principle of the aviation engine fuel metering device, the open-loop model of metering valve position with single (double) cavity indirect control mode was established in AMESim simulation platform.By analyzing the physical mechanism of the single (double) cavity control structure model, the open-loop transfer function from the input current of the electro-hydraulic servo valve to the displacement of the metering valve core was established.In order to verify the accuracy of the theoretical model, it was compared with the nonlinear model in time domain and frequency domain.The important structural parameters of control cavity area ratio and spring stiffness coefficient in the single (double) cavity control scheme- were selected, and the influence of structural parameters on the stability and dynamic characteristics of the metering device was analyzed.The results show that the theoretically derived linear model meets the actual requirement of model linearization and has high reliability.The single (double) cavity control scheme can meet the engineering requirements in terms of stability, the single cavity control scheme is suitable for the asymmetric design scheme of metering valve, and the double-cavity control scheme is suitable for the asymmetric design scheme or symmetric design scheme of metering valve with high area ratio.