An analytic expression for closed-loop output behavior under multiloop PID control

2004 ◽  
Vol 21 (1) ◽  
pp. 1-5 ◽  
Author(s):  
Byung-Su Ko ◽  
Thomas F. Edgar ◽  
Jietae Lee
2014 ◽  
Vol 525 ◽  
pp. 583-587
Author(s):  
Bing Tu ◽  
Wei Zhang ◽  
Teng Xi Zhan

This paper presented a excitation liquid-cooled retarder control system based on a microprocessor MC9SXS128. In order to achieve the constant speed, It used PWM to adjust the output current of excitation liquid-cooled retarder. It analyzed and calculated the inductance value in PWM output circuit and also analyzed the excitation liquid-cooled retarder control systematical mathematical model . It divided the brake stalls based on the current flowing through the field coil. by adding the PID closed-loop control system, the retarder could quickly reach the set speed. It tested the PID control algorithm at the experiments in retarder drum test rig and the results show that the control algorithm has good control performance to meet the application requirements.


2010 ◽  
Vol 148-149 ◽  
pp. 168-171
Author(s):  
Ning Shan

The kinematics model of planar closed-loop five-bar mechanism is established in this paper. The influence of mechanism’s input parameters on the output kinematics parameters is investigated by simulation. The five-bar mechanism is designed. The experimental system of hybrid actuators five-bar mechanism is established based PID control method. The experiment investigates the influence of mechanism’s input parameters on the output kinematics parameters. The results show that the mechanism’s output kinematics parameters depend on input parameters. The original angle of input bar is bigger, curves of kinematics parameters of output bar change more acutely. Applying PID control algorithm to control the hybrid actuators linkage, the real kinematics parameters of linkage are almost consistent with theory values and the error is less.


2011 ◽  
Vol 271-273 ◽  
pp. 983-986
Author(s):  
Ren He Zhen

This article employs single closed loop of voltage negative feedback circle to explore the welding wire sending system of arc welder, as the system of this style has the feature of rough sending and poor dynamic behavior. A double closed loop PWM digit speed adjustment system is proposed based on fussy adaptive-adjusting PID control algorithm. The experiment result indicates that this control system not only has a sound dynamic behavior and static behavior but also has a strong self-adapting behavior, and mostly eliminates the arc flutter made by the rough welding wire sending system.


2013 ◽  
Vol 341-342 ◽  
pp. 834-838
Author(s):  
Yan Xiang Wu ◽  
Chao Jun Zhang ◽  
Hai Bo Huo ◽  
Chao Qun Zhou

According to the requirement of smooth operation and accurate positioning for DC speed regulating system of mine hoist, a new speed control system that based on double closed-loop of Fuzzy-PID was designed. The best control scheme for mine hoist was also validated by simulation comparison with conventional PID control system in the MATLAB/Simulink. The result showed that the proposal was feasible and had practical value.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yan Liu ◽  
Yan Huang ◽  
He Zhang ◽  
Qiang Huang

AbstractIn the paper, adaptive neural fuzzy (ANF) PID control is applied on the stability analysis of phase-shifted full-bridge (PSFB) zero-voltage switch (ZVS) circuit, which is used in battery chargers of electric vehicles. At first, the small-signal mathematical model of the circuit is constructed. Then, by fuzzing the parameters of PID, a closed-loop system of the small-signal mathematical model is established. Further, after training samples collected from the fuzzy PID system by adaptive neural algorithm, an ANF PID controller is utilized to build a closed-loop system. Finally, the characteristics of stability, overshoot and response speed of the mathematical model and circuit model systems are analyzed. According to the simulation results of PSFB ZVS circuit, the three control strategies have certain optimizations in overshoot and adjustment time. Among them, the optimization effect of PID control in closed-loop system is the weakest. From the results of small-signal model and circuit model, the ANF PID system has highest optimization. Experiments demonstrate that the ANF PID system gives satisfactory control performance and meets the expectation of optimization design.


2013 ◽  
Vol 21 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Michael Same ◽  
Hossein Rouhani ◽  
Kei Masani ◽  
Milos Popovic

Considerable demand exists for a device to facilitate hands-free, stable stance in individuals with neurological disorders such as spinal cord injury (SCI) and stroke. In this regard, applying functional electrical stimulation (FES) to muscles of the lower limbs in closed loop has shown promise. In particular, it has been suggested that a PID control strategy could offer functional benefits to stability by mimicking the neurological control strategy employed in able-bodied stance. In this proof of concept study, we tested this assertion by examining the potential of a PID control strategy with gravity compensation to effectively maintain balance during quiet stance by regulating FES-induced contractions of the ankle plantarflexors and dorsiflexors in able-bodied individuals. A novel Inverted Pendulum Standing Apparatus (IPSA) was employed to simulate quiet stance whilst minimizing the voluntary control of able-bodied subjects. Quiet and perturbed standing trials were performed in 3 able-bodied subjects. Performance metrics including those pertaining to stability during quiet stance (root mean square difference), perturbation rejection capabilities (settling time, peak deviation), and ability to transition from an offset initial position (settling time), were examined. For all 3 subjects and for all of the metrics examined, our results showed that the proposed closed-loop controlled FES system improved performance in comparison to voluntary control. These results indicate that the PID plus gravity control strategy used in this study offers meaningful benefits over voluntary control in terms of standing stability. Thus, the controller could potentially be applied to the problem of improving or restoring standing ability in some neurologic patient populations.


2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Purushottama Rao Dasari ◽  
A. Seshagiri Rao

Abstract Control of unstable systems with time delays usually result in overshoots in the closed loop responses. The intricacy involved in multivariable unstable processes further makes the problem more challenging. In industry, set-point weighting is one of the recommended methods to minimize the overshoot. However, design of the set-point weighting parameters determines the percentage of minimization of the overshoot. In this paper, a method is proposed to design the set-point weighting parameters for unstable multivariable processes which is relatively simple and also reduces the overshoot. Weighting is considered for both proportional (β) and derivative (γ) terms in the PID control law. In the closed loop relation for set-point tracking, the coefficients of ‘s’ and ‘s3’ both in the numerator and denominator are made equal in order to find dynamically β and γ. The obtained expressions for β and γ are simple and dynamically depends on the controller parameters and are applied to TITO systems in present work. Decouplers are used in TITO systems mainly to reduce the interaction between the loops so that they can be viewed as independent loops. Decoupler design suggested by (Hazarika and Chidambaram [1] has been used in this work and two TITO unstable processes with time delays are illustrated here. Comparison with the reported methods available in literature verifies that the proposed method gives improved closed loop performance.


Sign in / Sign up

Export Citation Format

Share Document