MPC generally needs a digital control system to implement in practical. It is a typical digital control method, and digital control systems generally have the problem of one-step delay. In motor control, the existence of a one-step delay in the system lead to undesirable consequences such as current ripple, increased oscillation, and weakened stability. In this paper, aiming at the one-step delay problem of the permanent magnet synchronous motor MPC control system, the extended state observer (ESO) is used for closed-loop delay compensation. This method can improve the anti-interference ability of the system, and has obvious suppression effect on parameter perturbation and unknown disturbance that appear during system operation. Finally, it was verified by Simulink, and compared with non-compensation and commonly used compensation methods based on the actual model of the motor. The results show that the proposed method has good one-step delay compensation characteristics and can effectively improve the control effect of finite set model predictive current control (FCS-MPCC).

博物馆APP是传统博物馆形态与新兴数字技术相结合的产物,它的出现突破了传统博物馆与大众之间的时空限制,使博物馆与大众的交互方式更加便捷、高效、灵活、丰富.本文从当前国内外博物馆APP的现状分析出发,从用户体验设计的战略层、范围层、结构层、框架层和表现层等五大层面综合考虑,探讨数字化语境下结合了博物馆特色与智能终端优势的博物馆APP体验设计新模式.

The fray fault of the aircraft wire is common,but it considered difficult to be detected. Now it would be a serious threat to the safety of the aircraft. As the flight of the aircraft, the fray fault can be more and more serious and it would become open or short circuit at last. If the wire fault degree can be detected accurately, it will make important significance to life prediction of wire. A quantitative detection method for wire fray fault is brought out in this paper. Characteristic impedance is selected for describing wire fray fault by theoretically analysis. Simulation model of wire damage is presented and the quantitative relationship between characteristic impedance and wire damage is calculated by FEM analysis. The rule of characteristic impedance changing over time is obtained according to the data gained from the friction-wear test. The result shows that the characteristic impedance of wire increases linearly with time. The proposed method is beneficial for quantitative detection for wire fray fault and prediction for the remaining life.

提出一种基于GPS的巡道工巡道作业监控系统来解决铁路工务部门保证巡道作业质量的一种新思路,并对系统手持机的设计要求作了较充分的介绍,对上位机的软件应具备的功能作了阐述.现场实验数据表明,该系统的技术路线可行,有利于加强巡道作业的质量监控和责任追究.

This paper proposes a hybrid active power filter consisting of a small-rated active power filter and a single-tuned passive filter. It can efficiently damp harmonic resonance in industrial power system. The traditional passive filter (PF) has to decrease its factor quality to satisfy filter request at the cost of the damping effect of the harmonic resonance. The method proposed in this paper can infinitely increase the factor quality of PF by properly controlling the active power filter, and then the harmonic resonance is significantly mitigated. Furthermore, experimental results verify the feasibility and effectiveness of the hybrid active filter.