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在燃油泵调节器模态分析过程中,高集成装配体的模型简化和以螺钉连接为主的多种连接方式的有限元建模对分析结果的影响是一个难点.本文从实际工程应用角度出发,提出了关键子结构验证结合整体有限元建模的模态分析方法.首先,根据燃油泵调节器的结构特点对模型进行简化和网格处理;然后,开展了关键子结构壳体模态的仿真分析和实验测试,并在V... 相似文献
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针对某型航空发动机空中降转故障,从改变燃油流量调节器的供油特性方面分析其发生的主要原因,提出了核心排故途径,即改变膜盒组件相关设计参数。 相似文献
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REALIZATION OF FUZZY-FILTER CONTROL ON A BRUSHLESS AC GENERATOR 总被引:5,自引:0,他引:5
CHEN Zhi-hui 《中国航空学报》2000,13(3):172-176
AC generators have adopted transistor volt-age regulators widely traditionally.The researchon the digital voltage regulators has arousedstrong interest[1~ 3] .The digital voltage regula-tors have some advantages on the transistor reg-ulators[4 ] : ( 1 ) They can realize advanced control algo-rithm; ( 2 ) They have communication function; ( 3) They have data record function. Recently,the DSPs ( Digital Signal Proces-sors) have been widely applied in digital controlarea with… 相似文献
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杨守环 《中国民航学院学报》1989,(4)
当同步发电机输出电流大小与功率因数改变时,其电枢反应与内阻抗压降将改变,则发电机输出电压也将改变。为使发电机输出电压保持额定值,通常都有自动电压调节器与发电机配套工作。本文较详细地分析了MD-80飞机使用的AVR403型电压调节器各部分电路的工作原理,以及整机调压的工作过程,并阐述了该调压器的特点。 相似文献
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The electro-hydrostatic actuator (EHA) is a kind of power-by-wire (PBW) actuator that converts the electrical power into localized hydraulic power for flight control. By removing the central hydraulic power supply together with hydraulic pipes, an EHA's reliability and efficiency are greatly improved but its frequency width and stiffness decreased. To overcome the drawback, this article proposes a novel structure of EHA associated with a power regulator. Composed of a high-pressure accumulator and a proportional valve, it can store and harness the hydraulic power flexibly according to the changing control requirements. The concept of transferred volume is put forward to estimate the capability of the power regulator. The actuator output position can be kept fixed with a hydraulic lock. The compounded control is specially developed to ensure the actuator system to operate in a correct manner. The simulation results indicate that the new-brand actuator results in efficient expanding of the system frequency width with an optimal power supply. 相似文献
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《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013,52(12):2067-2079
In this study the gravitational perturbations of the Sun and other planets are modeled on the dynamics near the Earth–Moon Lagrange points and optimal continuous and discrete station-keeping maneuvers are found to maintain spacecraft about these points. The most critical perturbation effect near the L1 and L2 Lagrange points of the Earth–Moon is the ellipticity of the Moon’s orbit and the Sun’s gravity, respectively. These perturbations deviate the spacecraft from its nominal orbit and have been modeled through a restricted five-body problem (R5BP) formulation compatible with circular restricted three-body problem (CR3BP). The continuous control or impulsive maneuvers can compensate the deviation and keep the spacecraft on the closed orbit about the Lagrange point. The continuous control has been computed using linear quadratic regulator (LQR) and is compared with nonlinear programming (NP). The multiple shooting (MS) has been used for the computation of impulsive maneuvers to keep the trajectory closed and subsequently an optimized MS (OMS) method and multiple impulses optimization (MIO) method have been introduced, which minimize the summation of multiple impulses. In these two methods the spacecraft is allowed to deviate from the nominal orbit; however, the spacecraft trajectory should close itself. In this manner, some closed or nearly closed trajectories around the Earth–Moon Lagrange points are found that need almost zero station-keeping maneuver. 相似文献