High-Performance Closed-Loop Control and Its Constraints

2019 ◽  
pp. 335-372
Author(s):  
Zhengming Zhao ◽  
Liqiang Yuan ◽  
Hua Bai ◽  
Ting Lu
Keyword(s):  
High Performance ◽  
Closed Loop ◽  
Closed Loop Control ◽  
Loop Control

scholarly journals Static and Dynamic Characterization and Control of a High-Performance Electro-Hydraulic Actuator

Actuators ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 46
Author(s):  
Govind N. Sahu ◽  
Suyash Singh ◽  
Aditya Singh ◽  
Mohit Law
Keyword(s):  
Machine Tool ◽  
High Performance ◽  
Closed Loop ◽  
Dynamic Models ◽  
Static Model ◽  
Dynamical Model ◽  
Model Parameters ◽  
Closed Loop Control ◽  
Hydraulic Actuator ◽  
Loop Control

This paper characterizes the static, dynamic, and controlled behavior of a high-performance electro-hydraulic actuator to assess its suitability for use in evaluating machine tool behavior. The actuator consists of a double-acting piston and cylinder arrangement controlled by a servo valve and a separate rear chamber controlled by a separate valve, designed to work in conjunction to generate static forces of up to 7000 N that can be superposed with dynamic forces of up to ±1500 N. This superposition of periodic forces with a non-zero mean makes the actuator capable of applying realistic loading conditions like those experienced by machines during cutting processes. To characterize the performance of this actuator, linearized static and dynamic models are described. Since experiments with the actuator exhibit nonlinear characteristics, the linearized static model is expanded to include the influence of nonlinearities due to flow, leakages, saturations, and due to friction and hysteresis. Since all major nonlinearities are accounted for in the expanded static model, the dynamical model remains linear. Unknown static and dynamical model parameters are calibrated from experiments, and the updated models are observed to capture experimentally observed behavior very well. Validated models are used to tune the proportional and integral gains for the closed-loop control strategy, and the model-based tuning in turn guides appropriate closed-loop control of the actuator to increase its bandwidth to 200 Hz. The statically and dynamically characterized actuator can aid machine tool structural testing. Moreover, the validated models can instruct the design and development of other higher-performance electro-hydraulic actuators, guide the conversion of the actuator into a damper, and also test other advanced control strategies to further improve actuator performance.

New Electromagnetic Design of Miniature AF VCM Actuator with Low Cost

2015 ◽  
Vol 32 (4) ◽  
pp. 421-426 ◽  
Author(s):  
C.-S. Liu ◽  
L. Kuo ◽  
B.-J. Tsai
Keyword(s):  
High Performance ◽  
Closed Loop ◽  
Cell Phones ◽  
Low Cost ◽  
Voice Coil Motor ◽  
Open Loop ◽  
Closed Loop Control ◽  
Electromagnetic Design ◽  
Loop Control ◽  
Auto Focusing

AbstractRecently, compact and high-resolution camera modules with auto-focusing (AF) function have been integrated into cell phones in order to capture sharp photographs. Consumer demands AF camera modules in cell phones to have high performance with low cost. Accordingly, the present study proposes a new electromagnetic design of miniature AF voice coil motor (VCM) actuator with closed-loop control for cell phone camera modules to satisfy the requirements. The structure of the proposed AF VCM actuators was designed by using simulation methods. The performance of the proposed AF VCM actuators was demonstrated by a laboratory-built prototype. The experimental results have shown that the proposed AF VCM actuator has excellent performance with lower power consumption, higher positioning repeatability, and lower cost, when compared to previous AF VCM actuators with open-loop control or closed-loop control.

scholarly journals Design and Analysis of Closed Loop Control of Multilevel SVPWM Inverter Fed PMSM Drive

2019 ◽  
Vol 8 (6S2) ◽  
pp. 809-816
Keyword(s):  
Permanent Magnet ◽  
Feedback Linearization ◽  
High Performance ◽  
Closed Loop ◽  
Permanent Magnet Synchronous Motor ◽  
Voltage Source ◽  
Closed Loop Control ◽  
Loop Control ◽  
Controlled Switching ◽  
Switching Devices

Permanent magnet synchronous machines have been universally used over induction machines in variable speed drives. For present trends and future developments, power electronics technology gives the extensive research of multilevel inverters that brings high safety voltages with low harmonic content in comparison with two-level inverter strategies. Multi level inverters implementation can be done by raising the number of power semi conductor controlled switching devices per phase to increase the number of inverter output voltage levels. By increasing the levels, power controlled switching devices and other components are increased, which makes the inverter complex and overpriced. From the above aspects, three-phase three-level inverter strategy is used for high performance and high voltage A.C drives. Multilevel inverter using a space vector pulse width modulation (SVPWM) strategy gives great advantages in high performance A.C drive applications. Various types of control strategies have been recommended for voltage source inverter fed A.C drives. In the proposed work, a PI controller is designed for the outer loop and non-linear controller using a state feedback linearization technique is designed for the inner loop. The closed loop control system for three-level inverter fed Permanent magnet synchronous motor drive employing SVPWM is extensively simulated using MATLAB.

Remote Concrete Spraying in Shafts and Tunnels With Closed Loop Control

1996 ◽  
Author(s):  
Liu Hongzhao ◽  
E. Appleton
Keyword(s):  
High Performance ◽  
Closed Loop ◽  
Transformation Method ◽  
Emission Angle ◽  
Impact Angle ◽  
Order System ◽  
Closed Loop Control ◽  
Loop Control ◽  
Loop Control System ◽  
Velocity Measuring

Abstract In this paper, a closed-loop control system for the remote concrete spraying in shafts and tunnels is presented. The design includes a velocity measuring element, a PID controller, and a DC servo-motor drive system which is used to control the relative velocity of the grout, emission velocity, emission angle, and rotation to impact angle. The mathematical model of this system has been established and its transfer function obtained by the Laplace Transformation method. A set of stability conditions for this fourth-order system has been developed by means of the modified Hurwitz criterion. These studies provide the possibility of creating high-performance remote concrete spraying machines that operate in shafts and tunnels and have directional spray capability.

Study on Electro-Hydraulic Control System of the Parison Wall Thickness Based on the Double Closed-Loop Control Technology

2013 ◽  
Vol 278-280 ◽  
pp. 1516-1520
Author(s):  
Qiao Lian Du ◽  
Ke Hua Zhang
Keyword(s):  
Control System ◽  
Wall Thickness ◽  
High Performance ◽  
Closed Loop ◽  
Closed Loop Control ◽  
Hydraulic Control ◽  
Molding Machine ◽  
Proportional Valve ◽  
Loop Control ◽  
Hydraulic Control System

Abstract. Parison wall thickness electro-hydraulic control system is the core of parison wall thickness control for large scale blow molding machine. In order to ensure the equalization of the wall thickness for the hollow products and to save material, in this paper analyzed the project of the parison wall thickness electro-hydraulic control system for blow molding machine and designed the parison wall thickness electro-hydraulic positional closed-loop control system which adopted the high performance proportional valve. Through simulation analysis and experiment, it was proved that through positional feedback control of the core of high performance proportional valve, the response frequency of the electro-hydraulic proportional valve can be improved so as to improve the dynamic quality of the system, achieved the requirement for higher control precision and dynamic response and satisfied the requirement for fast speed and control precision for plastic extrusion-blow hollow molding machine. It can be seen that it is effective to adopt the closed-loop control strategy for Parison wall thickness electro-hydraulic control system and more important, it has operation significance for improving the quality and ensure the precision of the products.

Robust Control of Robotic Manipulators with Model-Based Precompensation and SMC Postcompensation

1993 ◽  
Vol 207 (2) ◽  
pp. 97-103 ◽  
Author(s):  
G S Hong ◽  
H A Zhu ◽  
C L Teo ◽  
A N Poo
Keyword(s):  
High Performance ◽  
Closed Loop ◽  
High Reliability ◽  
Robotic Manipulators ◽  
State Feedback Control ◽  
Closed Loop Control ◽  
Loop Control ◽  
Model Based ◽  
Loop Control System ◽  
Error Dynamics

Robust and reliable control of robotic manipulators is studied. A model-based precompensation configuration is first used to decouple and linearize the highly complicated electromechanical dynamics of robotic manipulators. Then a linear state-feedback control law is used for closed-loop control. Finally, simplified SMC is adopted to postcompensate for the resulting error dynamics of the closed-loop control system. It is shown that the intentionally introduced control redundancy will not only ensure global high performance for the resulting system, but will also provide the system with built-in high reliability.

scholarly journals Instability Condition Derivation for Hydraulic AGC System under Pressure Closed-Loop Control

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Yong Zhu ◽  
Guangpeng Li ◽  
Shengnan Tang ◽  
Wanlu Jiang ◽  
Pengfei Qian ◽  
...  
Keyword(s):  
Information Transfer ◽  
High Performance ◽  
Closed Loop ◽  
Block Diagram ◽  
Transfer Model ◽  
Closed Loop Control ◽  
Instability Mechanism ◽  
Instability Condition ◽  
Strip Rolling ◽  
Loop Control

In strip rolling, hydraulic automatic gauge control (HAGC) system is the key element to guarantee the precision of strip gauge. The stability of the kernel pressure closed loop (PCL) in the HAGC system plays an essential role in guaranteeing the rolling process with high performance. Nevertheless, there is some difficulty in exploring the instability mechanism of the HAGC system due to the fact that the PCL is a representative nonlinear closed-loop control system. In this work, for each component of the HAGC system, the mathematical model was established. And on the basis of the linking relation of various elements, we derived the incremental transfer model of the PCL system. Furthermore, in accordance with the deduced information transfer relation, the transfer block diagram of disturbing variable of the PCL system was obtained. Moreover, for the purpose of deriving the instability condition of the PCL system, the Popov frequency criterion was employed. The instability conditions of the HAGC system were obtained under PCL control. Furthermore, the derived instability conditions of the HAGC system were experimentally verified under various working conditions. The research results provide a fundamental foundation for studying the instability mechanism of the HAGC system.

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