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This paper intends to provide theoretical basis for matching design of hydraulic load simulator (HLS) with aerocraft actuator in hardware-in-loop test, which is expected to help actuator designers overcome the obstacles in putting forward appropriate requirements of HLS. Traditional research overemphasizes the optimization of parameters and methods for HLS controllers. It lacks deliberation because experimental results and project experiences indicate different ultimate performance of a specific HLS. When the actuator paired with this HLS is replaced, the dynamic response and tracing precision of this HLS also change, and sometimes the whole system goes so far as to lose control. Based on the influence analysis of the preceding phenomena, a theory about matching design of aerocraft actuator with HLS is presented, together with two paired new concepts of "Standard Actuator" and "Standard HLS". Further research leads to seven important conclusions of matching design, which suggest that appropriate stiffness and output torque of HLS should be carefully designed and chosen for an actuator. Simulation results strongly support that the proposed principle of matching design can be anticipated to be one of the design criteria for HLS, and successfully used to explain experimental phenomena and project experiences. 相似文献
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Transient performance and intelligent combination control of a novel spray cooling loop system 总被引:2,自引:1,他引:1
Effective thermal control systems are essential for the reliable working of insulated gate bipolar transistors (IGBTs) in many applications. A novel spray cooling loop system with integrated sintered porous copper wick (SCLS-SPC) is proposed to meet the requirements of higher device level heat fluxes and the harsh environments in some applications such as hybrid, fuel cell vehicles and aerospace. Fuzzy logic and proportional-integral-derivative (PID) policies are applied to adjust the electronic temperature within a safe working range. To evaluate the thermal control effect, a mathematical model of a 4-node thermal network and pump are established for predicting the dynamics of the SCLS-SPC. Moreover, the transient response of the 4 nodes and vapor mass flowrate under no control, PID and Fuzzy-PID are numerically investigated and discussed in detail. 相似文献
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针对复杂电磁信号环境下雷达辐射源识别困难的问题,提出了一种基于多维几何形状的辐射源识别算法。借助几何形状将辐射源空间特征向量转换为平面向量,计算向量各夹角余弦值,再同辐射源数据库进行比较,实现辐射源型号的自动识别。仿真验证了提出的识别算法,识别率均在80%以上。 相似文献
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