A Passive Third-Order Cascade PLL Filter

2011 ◽  
Vol 255-260 ◽  
pp. 2262-2266
Author(s):  
Lin Feng ◽  
Chu Wu ◽  
Bo Jin ◽  
Zhen Yu Wu

In this paper, the traditional passive loop filter is improved, and a new type of Cascade Third-order filter structure and Graphical Phase Design method is proposed, which greatly simplifies high-order PLL filter’s design, analysis and calculation. According to graphical phase design principle, parameters for cascade third-order filter could be figured out from the given formula, the derived result is simulated in the form of Bode plots and Unit-step response with Pspice software and the loop target under different parameters is compared. Experiments show that this third-order filter could significantly improve the stability of PLL, deeply attenuate the phase detector’s high-frequency noise and is well adapted to the loop gain change. Users can also change the design parameters flexibly according to the system requirements with this filter.

1996 ◽  
Vol 33 (2) ◽  
pp. 134-156
Author(s):  
S. M. I. Lidgey

Classical control – a hybrid design method by inspection This article describes a method whereby most linear time – invariant SISO control systems dominated by no more than three time constants can be designed by a simple procedure, refined if necessary by empirical formulae. In many cases specifying the initial peak time of a classical third order step response is sufficient.


2013 ◽  
Vol 385-386 ◽  
pp. 125-128
Author(s):  
Ji Tao Chen ◽  
Hai Yan Song ◽  
Wei Wei Ge ◽  
Yuan Yuan Li

Drill tower is the support structure to ensure normal work for drilling, and the structural characteristic has been played a vital role in the stability of drilling rig. In the paper, the 3-D modeling of the drill tower has been established by the software UG and the finite element analysis of the structure has been finished by software ANSYS that it provides a new design method and thought for the new type of electro-hydraulic controlling core drill tower. According to the analysis result, the practicability for the structure is discussed, and furthermore, this study can provide reliable and efficient technical reference for future design of drill tower products.


2011 ◽  
Vol 110-116 ◽  
pp. 2590-2595 ◽  
Author(s):  
Ling Zhou ◽  
Wei Dong Shi ◽  
Wei Gang Lu

In this paper in order to develop high efficiency and high head deep-well pump, a L9 (34) orthogonal experiment was performed with four factors and three values including outlet angle, outlet width, the outside diameter of impeller back shroud, etc. 9 impellers were designed. The whole flow field of new-type two-stage deep-well pump at the operating point for design was simulated by FLUENT 6.2 using the standard model, SIMPLEC algorithm, second-order upwind scheme to solve, and analyze the independent of the number of the grid. 9 groups of the efficiency and head in design scheme were obtained. The effects of geometrical parameters on efficiency, head were researched using Latin square test method. The primary and secondary factors of the design parameters were acquired by way of variance analysis. According to the test result, an optimum program to further design was put forward. After manufactured and tested, the efficiency and head of the final optimal design models were significantly improved. The productions show good energy saving and material saving characters and could replace traditional pumps for deep well in the future, the comprehensive technical indicators achieve international advanced levels. The results would be instructive to the design method of new-type deep well pump.


Energies ◽  
2020 ◽  
Vol 13 (19) ◽  
pp. 4992
Author(s):  
Heng Li ◽  
Yu Zhang ◽  
Hongtao Liao ◽  
Jun Peng

Autonomous rail transit (ART) vehicle is a new type of urban rail transportation, which has good development prospects. It is powered by onboard supercapacitors, which are charged at midway stations. It requires short charging time and fast charging speed. Usually, multiple chargers are used in parallel for charging. However, this will cause an overshoot phenomenon during charging, and the overshoot of multiple chargers will be superimposed on the supercapacitor, affecting the stability and life of both supercapacitors and chargers. In this paper, we propose a predictive set point modulation charging method, which can reduce the system’s overshoot and increase the reliability of the system. First, the state-space averaging method is used to establish the electronic physical model of the multicharger system. Secondly, a predictive set point modulation charging control method is designed, and the closed-loop model of the proposed charging system is developed using the buck diagram. The effectiveness of the proposed method is verified through extensive simulation and experiments. The experimental results show that compared with the classical design method, the proposed method can effectively suppress the current overshoot.


2021 ◽  
Vol 13 (7) ◽  
pp. 168781402110343
Author(s):  
Mei Yang ◽  
Yimin Xia ◽  
Lianhui Jia ◽  
Dujuan Wang ◽  
Zhiyong Ji

Modular design, Axiomatic design (AD) and Theory of inventive problem solving (TRIZ) have been increasingly popularized in concept design of modern mechanical product. Each method has their own advantages and drawbacks. The benefit of modular design is reducing the product design period, and AD has the capability of problem analysis, while TRIZ’s expertise is innovative idea generation. According to the complementarity of these three approaches, an innovative and systematic methodology is proposed to design big complex mechanical system. Firstly, the module partition is executed based on scenario decomposition. Then, the behavior attributes of modules are listed to find the design contradiction, including motion form, spatial constraints, and performance requirements. TRIZ tools are employed to deal with the contradictions between behavior attributes. The decomposition and mapping of functional requirements and design parameters are carried out to construct the structural hierarchy of each module. Then, modules are integrated considering the connections between each other. Finally, the operation steps in application scenario are designed in temporal and spatial dimensions. Design of cutter changing robot for shield tunneling machine is taken as an example to validate the feasibility and effectiveness of the proposed method.


Robotica ◽  
2021 ◽  
pp. 1-14
Author(s):  
Hongkai Li ◽  
Xianfei Sun ◽  
Zishuo Chen ◽  
Lei Zhang ◽  
Hongchao Wang ◽  
...  

Abstract Inspired by gecko’s adhesive feet, a wheeled wall climbing robot is designed in this paper with the synchronized gears and belt system acting as the wheels by considering both motion efficiency and adhesive capability. Adhesion of wheels is obtained by the bio-inspired adhesive material wrapping on the outer surface of wheels. A ducted fan mounted on the back of the robot supplies thrust force for the adhesive material to generate normal and shear adhesion force whilemoving on vertical surfaces. Experimental verification of robot climbing on vertical flat surface was carried out. The stability and the effect of structure design parameters were analyzed.


Mathematics ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1434 ◽  
Author(s):  
Wonhee Kim ◽  
Sangmin Suh

For several decades, disturbance observers (DOs) have been widely utilized to enhance tracking performance by reducing external disturbances in different industrial applications. However, although a DO is a verified control structure, a conventional DO does not guarantee stability. This paper proposes a stability-guaranteed design method, while maintaining the DO structure. The proposed design method uses a linear matrix inequality (LMI)-based H∞ control because the LMI-based control guarantees the stability of closed loop systems. However, applying the DO design to the LMI framework is not trivial because there are two control targets, whereas the standard LMI stabilizes a single control target. In this study, the problem is first resolved by building a single fictitious model because the two models are serial and can be considered as a single model from the Q-filter point of view. Using the proposed design framework, all-stabilizing Q filters are calculated. In addition, for the stability and robustness of the DO, two metrics are proposed to quantify the stability and robustness and combined into a single unified index to satisfy both metrics. Based on an application example, it is verified that the proposed method is effective, with a performance improvement of 10.8%.


2021 ◽  
Vol 11 (7) ◽  
pp. 3017
Author(s):  
Qiang Gao ◽  
Siyu Gao ◽  
Lihua Lu ◽  
Min Zhu ◽  
Feihu Zhang

The fluid–structure interaction (FSI) effect has a significant impact on the static and dynamic performance of aerostatic spindles, which should be fully considered when developing a new product. To enhance the overall performance of aerostatic spindles, a two-round optimization design method for aerostatic spindles considering the FSI effect is proposed in this article. An aerostatic spindle is optimized to elaborate the design procedure of the proposed method. In the first-round design, the geometrical parameters of the aerostatic bearing were optimized to improve its stiffness. Then, the key structural dimension of the aerostatic spindle is optimized in the second-round design to improve the natural frequency of the spindle. Finally, optimal design parameters are acquired and experimentally verified. This research guides the optimal design of aerostatic spindles considering the FSI effect.


2013 ◽  
Vol 791-793 ◽  
pp. 799-802
Author(s):  
Ya Ping Wang ◽  
H.R. Shi ◽  
L. Gao ◽  
Z. Wang ◽  
X.Y. Jia ◽  
...  

With the increasing of the aging of population all over the world, and With the inconvenience coming from diseases and damage, there will be more and more people using the wheelchair as a tool for transport. When it cant be short of the wheelchair in the daily life, the addition of the function will bring the elevation of the quality of life for the unfortunate. Staring with this purpose, the research designs a pickup with planetary bevel gear for the wheelchair. After determining the basic function of the wheelchair aids, the study determines the design parameters by using the knowledge of parametric design and completes the model for the system with Pro/E, on the other hand, it completes key components optimization analysis which is based on genetic algorithm optimization.


Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 823
Author(s):  
Wen-Jer Chang ◽  
Yu-Wei Lin ◽  
Yann-Horng Lin ◽  
Chin-Lin Pen ◽  
Ming-Hsuan Tsai

In many practical systems, stochastic behaviors usually occur and need to be considered in the controller design. To ensure the system performance under the effect of stochastic behaviors, the controller may become bigger even beyond the capacity of practical applications. Therefore, the actuator saturation problem also must be considered in the controller design. The type-2 Takagi-Sugeno (T-S) fuzzy model can describe the parameter uncertainties more completely than the type-1 T-S fuzzy model for a class of nonlinear systems. A fuzzy controller design method is proposed in this paper based on the Interval Type-2 (IT2) T-S fuzzy model for stochastic nonlinear systems subject to actuator saturation. The stability analysis and some corresponding sufficient conditions for the IT2 T-S fuzzy model are developed using Lyapunov theory. Via transferring the stability and control problem into Linear Matrix Inequality (LMI) problem, the proposed fuzzy control problem can be solved by the convex optimization algorithm. Finally, a nonlinear ship steering system is considered in the simulations to verify the feasibility and efficiency of the proposed fuzzy controller design method.


Sign in / Sign up

Export Citation Format

Share Document