Journal articles: 'Feedforward control loop'

1

Wei, Kang, Xin Xu, Yu Shu Deng, Jin Xing Chu, and Lu Yang. "Research and Implementation of High-Speed Positioning Control Base on Feedforward PID Control." Advanced Materials Research 940 (June 2014): 370–74. http://dx.doi.org/10.4028/www.scientific.net/amr.940.370.

Full text

Abstract:

Feedforward PID control of the current loop and speed loop based on the three closed loop PID servo control system was introduced here to improve the intermittent rotary positioning performance of the pick-and-place system. Feedforward PID control [1] is better than traditional PID control on command signal tracking under high-speed positioning control, which has been proved by Simulink simulation.

APA, Harvard, Vancouver, ISO, and other styles

2

Zhou, Hua, Lu Yu Wang, and Wei Chang. "A Design of Loop Control Method for Feedforward Power Amplifier." Advanced Materials Research 588-589 (November 2012): 731–34. http://dx.doi.org/10.4028/www.scientific.net/amr.588-589.731.

Full text

Abstract:

This letter delivered an analysis and design method of signal cancellation loop for feedforward power amplifier. To begin with the inherent defects of feedforward amplifier, it stated the merits and drawbacks of existing feedforward amplifier loop control methods, then put forward a new signal cancellation loop control method, namely separating amplitude feedback and phase feedback in signal cancellation loop, then advanced the theoretical analysis and calculation. The result of theoretical calculation was in line with the outcome of simulation, which confirmed through ADS (Advanced Design System) simulation. This method has multiple advantages: high feedback convergence rate, readily implementation and high linearity.

APA, Harvard, Vancouver, ISO, and other styles

3

Tomizuka, Masayoshi. "Zero Phase Error Tracking Algorithm for Digital Control." Journal of Dynamic Systems, Measurement, and Control 109, no. 1 (March 1, 1987): 65–68. http://dx.doi.org/10.1115/1.3143822.

Full text

Abstract:

A digital feedforward control algorithm for tracking desired time varying signals is presented. The feedforward controller cancels all the closed-loop poles and cancellable closed-loop zeros. For uncancellable zeros, which include zeros outside the unit circle, the feedforward controller cancels the phase shift induced by them. The phase cancellation assures that the frequency response between the desired output and actual output exhibits zero phase shift for all the frequencies. The algorithm is particularly suited to the general motion control problems including robotic arms and positioning tables. A typical motion control problem is used to show the effectiveness of the proposed feedforward controller.

APA, Harvard, Vancouver, ISO, and other styles

4

Sun, Zhenxing, Shihua Li, Jiegao Wang, Xinghua Zhang, and Xiaohui Mo. "Adaptive composite control method of permanent magnet synchronous motor systems." Transactions of the Institute of Measurement and Control 40, no. 11 (September 21, 2017): 3345–57. http://dx.doi.org/10.1177/0142331217719956.

Full text

Abstract:

With the development of digital signal processes, the relative differences of PMSM single loop in control periods between the speed loop and current loops are becoming smaller or even vanishing. Therefore, cascade control schemes seem to be unnecessary. In addition, considering the effects of disturbances and the variety of moments of inertia, this paper proposes a scheme using an adaptive non-cascade control method to design the controller, which merges speed loop and q-axis current loop into one single loop. First, an extended state observer (ESO) is employed to estimate the disturbances of the system. The estimated value is used in the feedforward compensation design to improve the capability of system anti-disturbance. Then, considering the performance degradation caused by inertia change, an adaptive control scheme is developed. By using inertia identification technology, the feedforward compensation gain can be tuned automatically according to the identification value. Several groups of simulations and experiments are carried out and the results demonstrate the effectiveness of the proposed scheme.

APA, Harvard, Vancouver, ISO, and other styles

5

Wang, Jian, Hendrik Van Brussel, and Jan Swevers. "Robust Perfect Tracking Control With Discrete Sliding Mode Controller." Journal of Dynamic Systems, Measurement, and Control 125, no. 1 (March 1, 2003): 27–32. http://dx.doi.org/10.1115/1.1540994.

Full text

Abstract:

The closed-loop transfer function of a plant controlled with a classical feedback controller, depends on the dynamics of the plant. Since most feedforward tracking controllers are designed based on this closed-loop transfer function, they are not robust against plant model uncertainties. Sliding-mode controllers have the property that when the system is on the switching line, the closed-loop behavior is independent of the plant dynamics. As a result, it can be expected that a feedforward control design based on this closed-loop behavior is robust against plant model uncertainties. This paper studies this feedforward robustness issue in detail and verifies the results on an experimental test setup: a stage driven by a linear motor. An integrated procedure is proposed in designing the closed-loop discrete-time sliding mode controller using the reaching law method.

APA, Harvard, Vancouver, ISO, and other styles

6

Meaburn, A., and F. M. Hughes. "Feedforward Control of Solar Thermal Power Plants." Journal of Solar Energy Engineering 119, no. 1 (February 1, 1997): 52–60. http://dx.doi.org/10.1115/1.2871838.

Full text

Abstract:

In recent years the problem of controlling the temperature of oil leaving an array of parabolic trough collectors has received much attention. The control schemes developed have in general utilized a feedback control loop combined with feedforward compensation. The majority of the published papers place the emphasis almost entirely on the design of the feedback control loop. Little or no attention has been paid to issues involved in the design of the feedforward controller. This paper seeks to redress this imbalance by concentrating upon the design and development of a feedforward controller for the ACUREX distributed solar collector field at the Plataforma Solar de Almeria. Different methods of combining feedback and feedforward will be assessed and experimental results will be presented in order to support any theoretical observations made.

APA, Harvard, Vancouver, ISO, and other styles

7

Tsao, Tsu-Chin, and Masayoshi Tomizuka. "Adaptive Zero Phase Error Tracking Algorithm for Digital Control." Journal of Dynamic Systems, Measurement, and Control 109, no. 4 (December 1, 1987): 349–54. http://dx.doi.org/10.1115/1.3143866.

Full text

Abstract:

This paper describes an adaptive feedforward controller to let the output of a plant with stable and unstable zeros track a time varying desired output. The dynamics of the closed loop system consisting of the plant and the feedback controller are assumed unknown or slowly varying due to changes on the plant parameters. In the control scheme proposed in this paper, the feedforward controller is adaptive while the feedback controller is fixed under the assumption that the closed loop system remains stable at all times. With a few samples of future reference input data available, the preview action of the adaptive feedforward controller cancels the phase lag caused by the closed loop dynamics and attains the zero phase error tracking performance (i.e., the plant output is in phase with any sinusoidal desired output) asymptotically.

APA, Harvard, Vancouver, ISO, and other styles

8

Clark, Robert L. "A Hybrid Autonomous Control Approach." Journal of Dynamic Systems, Measurement, and Control 117, no. 2 (June 1, 1995): 232–40. http://dx.doi.org/10.1115/1.2835184.

Full text

Abstract:

A hybrid autonomous control approach for active damping and control of a persistent disturbance is presented. Direct velocity feedback control is coupled with an adaptive feedforward controller to minimize the transient response and that due to a persistent disturbance, respectively. A time-averaged gradient descent algorithm was selected to adapt the feedforward filter, rendering the controller model-insensitive and thus autonomous for the chosen application. The feedback control loop serves to increase the damping of the controlled structure, decreasing the convergence time associated with the adaptive feedforward filter. Thus the integration of the two control approaches affords increases in performance previously not possible with the adaptive feedforward controller alone.

APA, Harvard, Vancouver, ISO, and other styles

9

Yang, Ying, Jing Yuan, and Hu Zhang. "Regulator Design of Vector Control System." Advanced Materials Research 383-390 (November 2011): 7082–89. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.7082.

Full text

Abstract:

A Decoupling method based on feedforward voltage compensation is adopted to eliminate completely the coupling between exciting current and torque current. Based on conventional design methods of single-variable linear system , the paper analyses and designs detailedly the flux loop, speed loop and current loop. A design method based on double closed-loop PI regulator for speed sensorless vector control system is proposed. Through experimental results, we demonstrate its good performance.

APA, Harvard, Vancouver, ISO, and other styles

10

Lee, Kyeong Ha, Seung Guk Baek, Hyouk Ryeol Choi, Hyungpil Moon, Sang-Hoon Ji, and Ja Choon Koo. "Feedforward model-inverse position control of three-stage servo-valve using zero magnitude error tracking control." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 7 (July 5, 2018): 2340–48. http://dx.doi.org/10.1177/0954406218786533.

Full text

Abstract:

Three-stage servo-valves are popularly used in hydraulic systems that require large flow rate and high pressure. For a proper control of flow direction and flow rate fed into a hydraulic actuator, securing a proper position control bandwidth is a critical task for the servo-valve. In this paper, a set of popular control methods are systematically studied and a control method is selected. It is proven that the feedforward model-inverse control is the most effective method in terms of the control bandwidth. In the present work, the feedforward closed-loop architecture is adopted and the closed-loop system is estimated in a linear discrete-time transfer function by recursive least squares method. On recognizing a nonminimum phase zero problem, this work implements the zero magnitude error tracking control, an approximate model-inverse technique, in order to overcome the problem. As a result, the effectiveness of the proposed feedforward model-inverse position control strategy is verified.

APA, Harvard, Vancouver, ISO, and other styles

11

Ren, Haijun, Hao Zhang, Guang Deng, and Bin Hou. "Feedforward Feedback Pitch Control for Wind Turbine Based on Feedback Linearization with Sliding Mode and Fuzzy PID Algorithm." Mathematical Problems in Engineering 2018 (June 20, 2018): 1–13. http://dx.doi.org/10.1155/2018/4606780.

Full text

Abstract:

After exceeding rated power, variable speed variable pitch wind turbines need to keep output powers at rated value by adopting pitch angles. With the typical nonlinear characteristics of the wind turbines, it is difficult to control accurately by conventional linear controller. Though feedback control can realize the stability of the system, it is effective only when deviations are produced. As such, feedforward control can be applied to compensate the time-delay produced by feedback control. Accordingly, we propose a compound control strategy that combines feedback controller with feedforward controller in this paper. In feedback loop, we adopt fuzzy algorithm to adjust the parameters of PID controller. Furthermore, to overcome large variation of input wind speed, variable universe theory is proposed to optimize fuzzy algorithm. In feedforward loop, we propose feedback linearization to address nonlinear problem. Furthermore, sliding mode algorithm is supplied to improve the robustness of feedback linearization. Therefore, feedforward loop can efficiently compensate time-delay deficiency of wind turbine systems. Simulation results show that the proposed controller can enhance the control accuracy and robustness of the system.

APA, Harvard, Vancouver, ISO, and other styles

12

Nagata, Fusaomi, Takanori Mizobuchi, Sho Yoshitake, Hitoshi Suzukawa, Hiroto Ishihara, and Keigo Watanabe. "A Workmanlike Orthogonal-Type Robot with a Force Input Device." Journal of Advanced Computational Intelligence and Intelligent Informatics 15, no. 7 (September 20, 2011): 888–95. http://dx.doi.org/10.20965/jaciii.2011.p0888.

Full text

Abstract:

In this paper, a workmanlike orthogonal-type robot with a force input device is presented. The control system is composed of a force feedback loop, a position feedback loop and a position feedforward loop. The force feedback loop controls the resultant force consisting of tool contact force and kinetic friction forces. The stability criterion of the force control system is briefly discussed. Also, the position feedback loop controls the position in only pick feed direction. The position feedforward loop leads the tool tip along a desired trajectory called Cutter Location data (CL data), in which the feed rate is suitably generated by a fuzzy reasoning according to each model’s curvature. Further, a fine stick-slip motion control strategy is added to the control system to improve the lapping efficiency. The fine stick-slip motion is orthogonally generated to the direction of tool movement. Finally, a force input device is presented for an operator to manually regulate the desired feed rate or the desired polishing force. The force input device allows the robot to realize cooperative motion between the automatic control and the manual control reflecting the operator’s skill. The effectiveness of the robot is examined through experiments.

APA, Harvard, Vancouver, ISO, and other styles

13

Zhou, Jiyao, Mustafa Alrayah Hassan, Jiaxuan Zhang, Mingxuan Hou, Shang Wu, Gaoqi Xing, and Song Chi. "Stabilization of Constant Power Loads in DC Microgrid Systems Using an Adaptive Continuous Control Set Model Predictive Control." Symmetry 13, no. 7 (June 22, 2021): 1112. http://dx.doi.org/10.3390/sym13071112.

Full text

Abstract:

This paper represents an adaptive continuous control set model predictive control (CCS-MPC) to solve the disturbance-caused instability problems in a DC microgrid consisting of symmetrical parallel buck converters, constant voltage loads (CVL), and constant power loads (CPL). The symmetric model of the system is founded at first to describe and analyze the disturbance-caused instability problem. To mitigate the instability by taking the disturbances into consideration, the proposed adaptive controller is made from a double loop feedback controller and a feedforward estimation algorithm. In the voltage loop of the double loop controller, a capacitor dynamic-based voltage controller is developed, while in the current loop, a CCS-MPC algorithm is modified and applied. Meanwhile, a feedforward algorithm is developed to estimate the disturbance information and send it to the double loop controller to improve its robustness, so the composite controller can maintain the bus voltage fixed at its reference and the symmetrical equal current sharing. Finally, comparative MATLAB simulations and OPAL-RT hardware-in-the-loop experiments are conducted to verify the effectiveness and dynamic performance of the proposed algorithm towards other previous nonlinear controllers.

APA, Harvard, Vancouver, ISO, and other styles

14

Alter, David M., and Tsu-Chin Tsao. "Control of Linear Motors for Machine Tool Feed Drives: Experimental Investigation of Optimal Feedforward Tracking Control." Journal of Dynamic Systems, Measurement, and Control 120, no. 1 (March 1, 1998): 137–42. http://dx.doi.org/10.1115/1.2801310.

Full text

Abstract:

This paper investigates the use of optimal l1 and H∞ model reference optimal feedforward control to enhance the tracking performance of a linear motor drive. Experimental work is presented which studies the effects of signal preview, tracking constraint, and reference model choice on tracking performance. Suboptimal l1 control where the closed-loop system has a zero on the unit circle due to integral action in the feedback controller is given special attention, and is seen to give near optimal performance for the system under study here. For the specific trajectory employed here, the best performing feedforward controllers were experimentally seen to reduce by more than half the maximum and rms tracking errors of the H∞ optimal feedback closed-loop systems.

APA, Harvard, Vancouver, ISO, and other styles

15

Huang, Peichen, Zhigang Zhang, and Xiwen Luo. "Feedforward-plus-proportional–integral–derivative controller for agricultural robot turning in headland." International Journal of Advanced Robotic Systems 17, no. 1 (January 1, 2020): 172988141989767. http://dx.doi.org/10.1177/1729881419897678.

Full text

Abstract:

Traveling along straight lines and headland turning are two common motions during the automatic guidance of agricultural machines. However, most studies focus on accurately following parallel tracks in the field and seldom consider the maneuvers at the end of each row. Moreover, numerous studies have mainly focused on planning the global trajectories in the entire field to increase field efficiency, and very few works are related to maneuver generation and vehicle control in headlands. In this study, a feedforward-plus-proportional–integral–derivative controller for a differential drive robot in headland turning was developed. The feedforward-plus-proportional–integral–derivative controller consisted of a feedforward and a feedback loop. The feedforward loop was designed based on the heading errors of a lookahead point on the planning path. The feedback loop was designed based on radial errors to improve the tracking accuracy. Field comparison tests of feedforward, feedback, and feedforward-plus-proportional–integral–derivative controllers were conducted. Experimental results showed that the feedforward-plus-proportional–integral–derivative had better tracking results and took less turning time.

APA, Harvard, Vancouver, ISO, and other styles

16

Miyashiro, J. K., and E. O. Feigl. "A model of combined feedforward and feedback control of coronary blood flow." American Journal of Physiology-Heart and Circulatory Physiology 268, no. 2 (February 1, 1995): H895—H908. http://dx.doi.org/10.1152/ajpheart.1995.268.2.h895.

Full text

Abstract:

Recent evidence shows that norepinephrine affects coronary blood flow not only by alpha-receptor-mediated vasoconstriction and by feedback metabolic vasodilation that occurs as a result of myocardial beta-receptor activation, but also by the direct activation of coronary vascular beta-receptors that increase flow in a feedforward manner. The implications of combined feedforward and feedback control in maintaining the balance between metabolism and flow were investigated in the present mass balance model. Feedback was represented by a closed loop and was based on the hypothesis that the regulated variables are myocardial PO2 and PCO2 and that divergence of these variables from their operating point values functions as the metabolic error signals that manipulate coronary vascular smooth muscle and flow to match metabolism. alpha-Receptor-mediated vasoconstriction and beta-receptor-mediated vasodilation are represented by feedforward open loops that are activated simultaneously with increases in metabolism. The postulated control schemes of 1) metabolic feedback control alone, 2) feedback plus alpha- and beta-adrenergic feedforward control, and 3) feedback plus beta-adrenergic feedforward control were able to simulate the steady-state increase in coronary flow and the decrease in coronary venous PO2 that occurs during comparable experimental conditions. The simulations demonstrate that 1) the speed and accuracy of the flow response improve as beta-adrenergic feedforward control is added and alpha-adrenergic feedforward control is removed from the control scheme, 2) high feedback gain also improves the accuracy of the flow response, but the penalty is instability, and 3) a lag in alpha-adrenergic feedforward control improves the stability of the coronary response.

APA, Harvard, Vancouver, ISO, and other styles

17

Zhu, Qi, and Jing Bo Shi. "Design of Three-Phase Voltage Source PWM Rectifier Using Feed-Forward Compensation." Applied Mechanics and Materials 260-261 (December 2012): 487–93. http://dx.doi.org/10.4028/www.scientific.net/amm.260-261.487.

Full text

Abstract:

The basic principle of three-phase PWM rectifier is analyzed and the mathematic model is established.Based on traditional voltage and current double feedback loops control structure, according to the balance of power relations between the input and output,feedforward compensation control of the grid voltage component is added in current loop,and feedforward compensation control of the load current is added in voltage loop.The design methods of current regulator and voltage regulator are given. This control strategy is effective to improve dynamic response of DC bus voltage when the load or grid voltage changes.Finally,simulation results show the effectiveness and correctness of the proposed control strategy.

APA, Harvard, Vancouver, ISO, and other styles

18

Qiu, H., and Q. Zhang. "Feedforward-plus-proportional-integral-derivative controller for an off-road vehicle electrohydraulic steering system." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 217, no. 5 (May 1, 2003): 375–82. http://dx.doi.org/10.1243/095440703321645089.

Full text

Abstract:

This paper presents the use of a feedforward-plus-proportional-integral-derivative (FPID) controller for improving the control performance of the electrohydraulic steering system on an offroad vehicle. The FPID controller used an inverse valve transform in the feedforward loop to compensate for an electrohydraulic steering system deadband and used a conventional PID feedback loop to minimize the tracking error in steering control. On-simulator evaluation tests verified that the FPID resulted in a superior steering rate tracking performance over both a feedforward controller and a PID controller. On-vehicle evaluation tests verified that this FPID controller could achieve prompt and accurate steering angle tracking for agricultural vehicle automated guidance applications.

APA, Harvard, Vancouver, ISO, and other styles

19

Wu, Sen-Tung, Fu-Yuan Chen, Min-Chu Chien, Jian-Min Wang, and Yan-Ying Su. "A Hybrid Control Scheme with Fast Transient and Low Harmonic for Boost PFC Converter." Electronics 10, no. 15 (July 31, 2021): 1848. http://dx.doi.org/10.3390/electronics10151848.

Full text

Abstract:

In this study, a new control strategy was proposed to improve transient response and the input current harmonic distortion of power factor correction (PFC) regulators operating in an average current mode. The proposed technique required only two additional gain selectors and a peak detector circuit on the feedforward voltage loop and output voltage feedback loops. It provided a direct reading for the average voltage value of feedback control loops and the peak voltage of feedforward control loops, producing PFC boost regulators with fast dynamic responses and low-input current harmonic distortion. The use of digital potentiometers for directly changing the gain of control loops did not require any divider or squarer to reduce the complexity of control circuits. The operating principles and control strategies of 300 W boost PFC with the new control strategy are presented with detailed analysis and discussion. The experimental results were satisfactory.

APA, Harvard, Vancouver, ISO, and other styles

20

Gutiérrez-Frías, Octavio, Norma Lozada-Castillo, J. Alejandro Aguirre-Anaya, and Diego A. Flores-Hernández. "Nested Saturation Function Control of a Magnetic Levitation System." Complexity 2020 (April 29, 2020): 1–9. http://dx.doi.org/10.1155/2020/3545374.

Full text

Abstract:

The trajectory tracking task of a magnetic levitation system connected to a beam mechanism is solved by means of a nested saturation control with a feedforward term. The flatness property of the system allows to use the nested saturation control technique and the feedforward control to stabilize the output tracking error around the equilibrium. The closed-loop error dynamics is proven to be locally exponentially stable. Numerical simulations prove the effectiveness of the proposal.

APA, Harvard, Vancouver, ISO, and other styles

21

Liu, Liang, and Ming Gao. "State Feedback Control for Stochastic Feedforward Nonlinear Systems." Mathematical Problems in Engineering 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/908459.

Full text

Abstract:

This paper considers the state feedback stabilization problem for a class of stochastic feedforward nonlinear systems. By using the homogeneous domination approach, a state feedback controller is constructed to render the closed-loop system globally asymptotically stable in probability. A simulation example is provided to show the effectiveness of the designed controller.

APA, Harvard, Vancouver, ISO, and other styles

22

Wei, Sheng. "Theory Analysis and Performance Optimization of CNC Machine Tool Servo-Driven System." Applied Mechanics and Materials 331 (July 2013): 337–43. http://dx.doi.org/10.4028/www.scientific.net/amm.331.337.

Full text

Abstract:

The servo-driven system built a bridge between the numerical control device and machine tools and the robustness, rapidity and accuracy of CNC system are highly determinate by it. In this paper, a representative servo control module of CNC system will be addressed. Based on that, the mathematical models of close-loop controls with current-loop (integral element), position-loop (proportional element), speed-loop (derivative element) and feedforward control are established. The effect of static and dynamic performances are analyzed with the tuning parameters of each close-loop controller and the experimental verification are performed using the tool of SERVO GUIDE software.

APA, Harvard, Vancouver, ISO, and other styles

23

Yang, Tao, Ziwen Bai, Zhiqiang Li, Nenglian Feng, and Liqing Chen. "Intelligent Vehicle Lateral Control Method Based on Feedforward + Predictive LQR Algorithm." Actuators 10, no. 9 (September 9, 2021): 228. http://dx.doi.org/10.3390/act10090228.

Full text

Abstract:

Aiming at the problems of control stability of the intelligent vehicle lateral control method, single test conditions, etc., a lateral control method with feedforward + predictive LQR is proposed, which can better adapt to the problem of intelligent vehicle lateral tracking control under complex working conditions. Firstly, the vehicle dynamics tracking error model is built by using the two degree of freedom vehicle dynamics model, then the feedforward controller, predictive controller and LQR controller are designed separately based on the path tracking error model, and the lateral control system is built. Secondly, based on the YOLO-v3 algorithm, the environment perception system under the urban roads is established, and the road information is collected, the path equation is fitted and sent to the control system. Finally, the joint simulation is carried out based on CarSim software and a Matlab/Simulink control model, and tested combined with hardware in the loop test platform. The results of simulation and hardware-in-loop test show that the transverse controller with feedforward + predictive LQR can effectively improve the accuracy of distance error control and course error control compared with the transverse controller with feedforward + LQR control, LQR controller and MPC controller on the premise that the vehicle can track the path in real time.

APA, Harvard, Vancouver, ISO, and other styles

24

Fu, Chun Peng, and Yong Qiang Zhu. "Power Feedward Strategy of Grid-Connected Inverter Based on Direct Power Decoupling." Applied Mechanics and Materials 331 (July 2013): 311–14. http://dx.doi.org/10.4028/www.scientific.net/amm.331.311.

Full text

Abstract:

Take into account grid inverter that using direct power control is vulnerable to the disturbance of grid voltage, a control algorithm is proposed based on the relationship between the power and voltage, which is deduced according to the mathematic model of the inverter that using double-loop control strategy. The change amount of the output power of inverter is added to the reference of power closed-loop as power feedforward, which improves the dynamic response to the grid voltage change. Simulations with EMTDC/PSCAD are carried out and the comparison of output power response to grid voltage change between control with and without power feedforward verifies its effectiveness.

APA, Harvard, Vancouver, ISO, and other styles

25

Reeves, Gregory, Prasad Bandodkar, and Hadel Al Asafen. "Spatiotemporal control of gene expression boundaries using a feedforward loop." FASEB Journal 34, S1 (April 2020): 1. http://dx.doi.org/10.1096/fasebj.2020.34.s1.00347.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Eid, E. E., and F. M. Ghannouchi. "Adaptive nulling loop control for 1.7-GHz feedforward linearization systems." IEEE Transactions on Microwave Theory and Techniques 45, no. 1 (1997): 83–86. http://dx.doi.org/10.1109/22.552035.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Kazimierczuk, M. K., and A. J. Edstrom. "Open-loop peak voltage feedforward control of PWM buck converter." IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications 47, no. 5 (May 2000): 740–46. http://dx.doi.org/10.1109/81.847879.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Drop, Frank M., Daan M. Pool, Max Mulder, and Heinrich H. Bülthoff. "Constraints in Identification of Multi-Loop Feedforward Human Control Models." IFAC-PapersOnLine 49, no. 19 (2016): 7–12. http://dx.doi.org/10.1016/j.ifacol.2016.10.444.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Bandodkar, Prasad U., Hadel Al Asafen, and Gregory T. Reeves. "Spatiotemporal control of gene expression boundaries using a feedforward loop." Developmental Dynamics 249, no. 3 (January 23, 2020): 369–82. http://dx.doi.org/10.1002/dvdy.150.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Wen-lan, Wang, and Xiong-huai Bai. "P and Feedforward Control for Mobile Robot." Journal of Physics: Conference Series 2404, no. 1 (December 1, 2022): 012053. http://dx.doi.org/10.1088/1742-6596/2404/1/012053.

Full text

Abstract:

Abstract Wheeled mobile robots have a wide range of applications in aerospace, military, industry, medical services, and even entertainment. It is simple in design and easy in fabrication and is widely studied by scholars at home and abroad. However, the path-tracking problem of wheeled mobile robots has also been a key problem inhibiting their development. In this design, the kinematic model of the robot is constructed by using P and feedforward, and a double closed-loop P and feedforward control system is designed. After a trial-and-error method, the appropriate control parameters are obtained. The simul ink function in MATLAB is used to simulate and verify the path-following ability of the method.

APA, Harvard, Vancouver, ISO, and other styles

31

Zhang, Rong, and Andrew G. Alleyne. "Dynamic Emulation Using an Indirect Control Input." Journal of Dynamic Systems, Measurement, and Control 127, no. 1 (June 16, 2004): 114–24. http://dx.doi.org/10.1115/1.1876496.

Full text

Abstract:

This paper presents a generalized framework to analyze and design controllers for a class of dynamic emulation systems. This class of systems features some structurally distinctive control frameworks which inherently limit the available bandwidth for dynamic emulation. The primary focus is on control structures that we define as indirect. This means the signal from the controller does not affect the physical plant directly; it interacts in combination with other exogenous signals to affect a behavior on the physical system interacting with the emulated load. It is shown that the achievable closed-loop performance is limited in a unique way: the high-frequency response of the controlled closed-loop system converges to the dynamics of the open-loop physical plant that is interacting with the emulated load. This paper illustrates the three controller configurations of the indirect emulation and gives guidelines on how to improve the performance within the identified structural limitations. The three configurations are: a feedback design measuring plant output only, a feedforward design measuring an exogenous signal, and a two degree-of-freedom design combining feedback and feedforward measurements. A detailed analysis in the frequency domain is used to support the experimental results illustrated on a Hardware-in-the-Loop (HIL) system. The demonstration case is a high-bandwidth transient dynamometer to emulate rapidly varying loads associated with an earthmoving vehicle powertrain.

APA, Harvard, Vancouver, ISO, and other styles

32

Feliu, V., K. S. Rattan, and H. B. Brown. "Modeling and Control of Single-Link Flexible Arms With Lumped Masses." Journal of Dynamic Systems, Measurement, and Control 114, no. 1 (March 1, 1992): 59–69. http://dx.doi.org/10.1115/1.2896508.

Full text

Abstract:

This paper deals with the modeling and control of a special class of single-link flexible arms. These arms consist of flexible massless structures having some masses concentrated at certain points of the beam. In this paper, the dynamic model of such flexible arms is developed and some of the control properties are deduced. A robust control scheme to remove the effects of friction in the joins is proposed. The control scheme consists of two nested feedback loops, an inner loop to control the position of the motor and an outer loop to control the tip position. The inner loop is described in other publications. A simple feedforward-feedback controller is designed for the outer loop to drive the beam accurately along a desired trajectory. Effects of the changes in the tip’s mass are studied. This modeling and control method is then generalized to the distributed-mass flexible beam case. Finally, experimental results are presented.

APA, Harvard, Vancouver, ISO, and other styles

33

Li, Ziwei, Zheng Xu, Ridong Zhang, Hongbo Zou, and Furong Gao. "Design of modified 2-degree-of-freedom proportional–integral–derivative controller for unstable processes." Measurement and Control 53, no. 7-8 (July 30, 2020): 1465–71. http://dx.doi.org/10.1177/0020294020944954.

Full text

Abstract:

Concerning first-order unstable processes with time delays that are typical in chemical processes, a modified 2-degree-of-freedom proportional–integral–derivative control method is put forward. The system presents a two-loop structure: inner loop and outer loop. The inner loop is in a classical feedback control structure with a proportional controller intended for implementing stable control of the unstable process; the outer loop is in a 2-degree-of-freedom structure with feedforward control of set points, where the system’s tracking response of set points is separated from its disturbance response. To be specific, the system has a feedforward controller that is designed based on the controlled object models and mainly used for regulating the system’s set point tracking characteristics; besides, it has a feedback controller that is designed on the ground of direct synthesis of disturbance suppression characteristics to improve the system’s disturbance rejection. To verify the effectiveness, the system is put into a theoretical analysis and simulated comparison with other methods. Simulation results show that the system has good set point tracking characteristics and disturbance suppression characteristics.

APA, Harvard, Vancouver, ISO, and other styles

34

Wu, Peng, Penghui Qiang, Tao Pan, and Huaiquan Zang. "Double-Loop Control for Torque Tracking of Dry Clutch." Machines 10, no. 12 (December 1, 2022): 1142. http://dx.doi.org/10.3390/machines10121142.

Full text

Abstract:

Torque tracking is an important control target of a dry clutch. At present, the torque tracking control method of a dry clutch generally uses the relationship between the clutch torque and release bearing position obtained via experiment to convert the torque tracking control of the clutch into the position tracking control of the release bearing. However, due to the nonlinearity and time-varying parameters of the dry clutch, it is difficult to obtain an accurate and fixed relationship between torque and position. At the same time, there are also the nonlinearity and interference problems in the position tracking control process. In order to solve the above problems, this paper takes the torque tracking control process of the dry clutch in a three-speed automatic mechanical transmission of an electric vehicle as an example and proposes a double-loop control controller including torque loop and position loop. Firstly, the drive system dynamic model of electric vehicles and clutch actuator dynamic models is established. Secondly, the torque loop controller is established with the adaptive feedforward-feedback control method. The time-varying parameters are adaptively adjusted with adaptive feedforward control to solve the problem of the time-varying relationship between torque and position. In addition, the feedback control loop is added to improve the robustness of the controller. Thirdly, the position loop controller is established with the backstepping-based active disturbance rejection control method to solve the nonlinear and disturbance problems of the position tracking control. In the end, the torque loop and position loop are cascaded to form a double-loop controller, and the torque tracking control simulations of the dry clutch are carried out. The simulation results show that the double-loop controller has good control performance, and the effectiveness of the controller has been preliminarily verified.

APA, Harvard, Vancouver, ISO, and other styles

35

Kivanc, Omer, and Salih Ozturk. "Low-Cost Position Sensorless Speed Control of PMSM Drive Using Four-Switch Inverter." Energies 12, no. 4 (February 23, 2019): 741. http://dx.doi.org/10.3390/en12040741.

Full text

Abstract:

A low-cost position sensorless speed control method for permanent magnet synchronous motors (PMSMs) is proposed using a space vector PWM based four-switch three-phase (FSTP) inverter. The stator feedforward d q -axes voltages are obtained for the position sensorless PMSM drive. The q-axis current controller output with a first order low-pass filter formulates the rotor speed estimation algorithm in a closed-loop fashion similar to PLL (Phase Lock Loop) and the output of the d-axis current controller acts as the derivative representation in the stator feedforward voltage equation. The proposed method is quite insensitive to multiple simultaneous parameter variations such as rotor flux linkage and stator resistance due to the dynamic effects of the PI current regulator outputs that are used in the stator feedforward voltages with a proper value of K gain in the q-axis stator voltage equation. The feasibility and effectiveness of the proposed position sensorless speed control scheme for the PMSM drive using an FSTP inverter are verified by simulation and experimental studies.

APA, Harvard, Vancouver, ISO, and other styles

36

Wang, Song. "ADRC and Feedforward Hybrid Control System of PMSM." Mathematical Problems in Engineering 2013 (2013): 1–12. http://dx.doi.org/10.1155/2013/180179.

Full text

Abstract:

The permanent-magnet synchronous motor (PMSM) is a complex controlled object that is difficult to drive and control. In this study, the vector control strategy is adopted to drive the PMSM. The active disturbance rejection controller is used to achieve the closed-loop control of PMSM, which simplifies the computational complexity. A load torque observer and feedforward compensation component are designed to overcome the PMSM speed fluctuation of the load disturbance. An experimental system based on the DSP board is designed to test the controller performance. The results validate the control algorithm.

APA, Harvard, Vancouver, ISO, and other styles

37

Garabandić, D., and T. Petrović. "Robust Controllers for Pulse-Width-Modulated D.C./D.C. Converters Using Internal-Model-Control Design." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 207, no. 3 (August 1993): 127–34. http://dx.doi.org/10.1243/pime_proc_1993_207_331_02.

Full text

Abstract:

A linear feedback controller for pulse-width-modulated d.c./d.c. regulator is designed using a frequency domain optimization method based on internal-model-control theory. This method aims to produce suboptimal low-order controllers which are ‘robust’, in the sense that the closed-loop system is guaranteed to meet stability objectives in the presence of model uncertainty. The small-signal model of a d.c./d.c. converter is used for the controller design. The model uncertainty description derived here is based on experiments and non-linear modelling. The result of the synthesis is a family of controllers, and each member of this family satisfies the robust control objectives. All controllers have a multi-loop structure including two feedback loops and one feedforward loop. A detailed design of the controller, including experimental results, is presented.

APA, Harvard, Vancouver, ISO, and other styles

38

Yang, Xing, and Xiang Shun Li. "Analysis and Design on Course Control for Sail-Assisted Ship." Advanced Materials Research 1008-1009 (August 2014): 556–61. http://dx.doi.org/10.4028/www.scientific.net/amr.1008-1009.556.

Full text

Abstract:

Aiming at the problem that sail-assisted ship is easy to yaw because of sail’s lateral force and adjusts its course slowly due to wind, wave and other interferences on the sea, this paper put forward a feedforward feedback control method based on fuzzy system. According to the relationship between lateral force and yaw angle, a feedforward controller was designed to offset the yaw of ship. In order to correct the drift angle of ship automatically, the feedback controller was fulfilled to track the given course. Feedback control loop adopted fuzzy self-adjusting PD controller to make the drift angle be adjusted in time. The simulations indicate that the feedforward feedback control can suppress the disturbance produced by lateral force effectively, enhance the stability of the system and accelerate the response speed.

APA, Harvard, Vancouver, ISO, and other styles

39

Wang, Zhipeng, Seungmin Rho, Chifu Yang, Feng Jiang, Zhen Ding, Chunzhi Yi, and Baichun Wei. "Active Loading Control Design for a Wearable Exoskeleton with a Bowden Cable for Transmission." Actuators 10, no. 6 (May 24, 2021): 108. http://dx.doi.org/10.3390/act10060108.

Full text

Abstract:

Exoskeletons with a Bowden cable for power transmission have the advantages of a concentrated mass and flexible movement. However, their integrated motor is disturbed by the Bowden cable’s friction, which limits the performance of the force loading response. In this paper, we solve this problem by designing an outer-loop feedforward-feedback proportion-differentiation controller based on an inner loop disturbance observer. Firstly, the inner loop’s dynamic performance is equivalent to the designed nominal model using the proposed disturbance observer, which effectively compensates for the parameter perturbation and friction disturbance. Secondly, based on an analysis of the stability of the inner loop controller, we obtain the stability condition and discuss the influence of modeling errors on the inner loop’s dynamic performance. Thirdly, to avoid excessive noise from the force sensors being introduced into the designed disturbance observer, we propose the feedforward-feedback proportion-differentiation controller based on the nominal model and pole configuration, which improves the outer loop’s force loading performance. Experiments are conducted, which verify the effectiveness of the proposed methods.

APA, Harvard, Vancouver, ISO, and other styles

40

Lazarević, Mihailo, and Nikola Živković. "The advanced iterative learning control algorithm for rehabilitation exoskeletons." Scientific Technical Review 70, no. 3 (2020): 29–34. http://dx.doi.org/10.5937/str2003029l.

Full text

Abstract:

In this paper an advanced iterative learning control algorithm for rehabilitation exoskeletons is proposed. A simplified biomechanical model is used as the control object to verify control algorithm feasibility. The control design is proposed as two level controller consisting of inner and outer loop. In the inner loop the feedback linearization is applied to cancel out the model nonlinearities. In the outer loop the advanced iterative learning control algorithm of sgnPDD2 type is applied as a feedforward controller and classical PD controller as a feedback controller. Uncertainties are added in order to examine the controller design robustness. Numerical simulation is carried out.

APA, Harvard, Vancouver, ISO, and other styles

41

Guo, Jian, Li Gang Song, and Yong Yang. "A Research on the Control System of Wind Power Grid-Connected Inverter." Advanced Materials Research 181-182 (January 2011): 551–56. http://dx.doi.org/10.4028/www.scientific.net/amr.181-182.551.

Full text

Abstract:

PWM inverter, as the main part of wind power grid-connected system, directly determines the quality of the power sent finally to grid. It has become the focus of research to develop a high-performance inverter control system. Based on the analysis and establishment of the mathematical model of the grid inverter system, the vector control strategy based on the voltage directional technique is analyzed in this paper. It consists of two closed loops. The fluctuation of direct voltage is suppressed due to the existence of voltage outer loop. Current inner loop realizes the independent control over meritorious electric current and reactive current through the feedforward of grid voltage and the decoupling of grid-connected current, which makes the inverter power factor close to 1.

APA, Harvard, Vancouver, ISO, and other styles

42

Nguyen, P.-B., J. W. Sohn, and S.-B. Choi. "Position Tracking Control of a Flexible Beam Using a Piezoceramic Actuator with a Hysteretic Compensator." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 10 (April 22, 2010): 2141–53. http://dx.doi.org/10.1243/09544062jmes1927.

Full text

Abstract:

This article presents position tracking control of a flexible beam using a piezoelectric actuator. This is achieved by implementing both a feedforward hysteretic compensator of the actuator and a proportional-integral-derivative (PID) feedback controller. The Preisach model is adopted to develop the feedforward hysteretic compensator. In the design of the compensator, estimated displacement of the piezoceramic actuator is used based on the limiting triangle database that results from collecting data of the main reversal curve and the first-order ascending curves. Modal parameters of the flexible beam, such as natural frequency, are obtained using a finite element method. Experimental implementation is conducted for position tracking control and performance comparison is made among an open-loop feedforward compensator, a PID feedback controller without considering the effect of hysteresis, and a PID feedback controller integrated with the feedforward hysteretic compensator.

APA, Harvard, Vancouver, ISO, and other styles

43

Wang, Zhiguo, and Jun Chen. "Feedforward and Feedback Control Performance Assessment for Nonlinear Systems." Abstract and Applied Analysis 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/597805.

Full text

Abstract:

A performance assessment method for nonlinear feedforward and feedback control systems is proposed in this paper. First, the existence of minimum variance performance bound for two nonlinear systems with different structures is analyzed, and the closed-loop model of nonlinear system is obtained with the help of iterative orthogonal least squares identification method. Then, the technology of variance analysis is introduced to establish the variance contributions due to both disturbances and controller. A nonlinear performance index for the feedforward and feedback control systems is estimated using an ANOVA-like variance decomposition method. Finally, a meaningful example is simulated to show the effectiveness of our method.

APA, Harvard, Vancouver, ISO, and other styles

44

Chun-Liang Lin and Yi-Hsing Hsiao. "Adaptive feedforward control for disturbance torque rejection in seeker stabilizing loop." IEEE Transactions on Control Systems Technology 9, no. 1 (2001): 108–21. http://dx.doi.org/10.1109/87.896752.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

MASUDA, Arata, Kazusa FUKUDA, Daisuke IBA, Shigeyuki KOBAYASHI, Yoshitaka YAMASHITA, and Mitsuru IKEDA. "Feedforward control of pantograph contact force based on phase-locked loop (Phase-locked loop for control force generation)." Transactions of the JSME (in Japanese) 80, no. 815 (2014): DR0203. http://dx.doi.org/10.1299/transjsme.2014dr0203.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Kim, Hyeong-Jin, Yung-Deug Son, and Jang-Mok Kim. "Improved Position Control for an EGR Valve System with Low Control Frequency." Energies 13, no. 2 (January 17, 2020): 457. http://dx.doi.org/10.3390/en13020457.

Full text

Abstract:

An exhaust gas recirculation (EGR) valve position control system requires fast response without overshoot, but the low control frequency limits control bandwidth and results in poor position response. A novel EGR valve position control scheme is proposed to improve the position response at low control frequency. This is based on the feedforward controller, but the feedforward control loop is implemented without the position pattern generator or derivative. The proposed method estimates the acceleration command through the relationship between the position controller output, the speed command and the speed limiter, and compensates the cascaded proportional-proportional integral (P-PI) controller. In this method, many operations are not required and noise due to derivative is not generated. This method can improve the position response without much computation and derivative noise at the low control frequency. Experimental results are presented to verify the feasibility of the proposed position control algorithm.

APA, Harvard, Vancouver, ISO, and other styles

47

Chen, Yuansheng, Jinhao Qiu, Jose Palacios, and Edward C. Smith. "Tracking control of piezoelectric stack actuator using modified Prandtl–Ishlinskii model." Journal of Intelligent Material Systems and Structures 24, no. 6 (August 14, 2012): 753–60. http://dx.doi.org/10.1177/1045389x12455725.

Full text

Abstract:

This article presents the development of Prandtl–Ishlinskii hysteresis model and tracking control of piezoelectric stack actuator with severe hysteresis. Classical Prandtl–Ishlinskii model is a linearly weighted superposition of many backlash operators with different threshold and weight values, which inherits the symmetric property of the backlash operator at about the center point of the loop formed by the operators. To describe the asymmetric hysteresis of piezoelectric stack actuators, two modified operators were developed, one for ascending branches and another for descending branches. Based on this modified model, a feedforward controller was designed to compensate the hysteresis. Since the modified model describes the inverse of hysteresis, the feedforward controller and the hysteresis of piezoelectric stack actuator canceled each other. To attenuate the creep effect and reduce tracking error, a feedback controller was proposed to work with the feedforward controller. Experimental results show that this control scheme that combines feedforward and feedback controllers greatly improves the tracking of the piezoelectric actuator and the error is less than 0.15 µm.

APA, Harvard, Vancouver, ISO, and other styles

48

Liang, Jiaqi, Dustin Howard, Jose Restrepo, and Ronald Harley. "Feedforward Transient Compensation Control for DFIG Wind Turbines During Both Balanced and Unbalanced Grid Disturbances." Industry Applications, IEEE Transactions on 49, no. 3 (May 2013): 1452–63. http://dx.doi.org/10.1109/tia.2013.2253439.

Full text

Abstract:

A feedforward transient compensation (FFTC) control scheme with proportional-integral-resonant current regulators is proposed to enhance the low-voltage ride through (LVRT) capability of doubly fed induction generators (DFIGs) during both balanced and unbalanced grid faults. Compensation for the DFIG stator transient voltage is feedforward injected into both the inner current control loop and the outer power control loop. The FFTC current controller improves the transient rotor-current control capability and minimizes the DFIG control interruptions during both balanced and unbalanced grid faults. Without the need of sequence-component decomposition, the torque ripple is reduced by injecting 60- and 120-Hz rotor-current components during unbalanced stator voltage conditions. The proposed FFTC control introduces minimal additional complexity to a regular DFIG vector-control scheme and shows promising enhancements in the LVRT capability of DFIGs. Simulation and experimental results are presented to demonstrate the effectiveness of the proposed FFTC control scheme.

APA, Harvard, Vancouver, ISO, and other styles

49

Sui, Wenbo, and Carrie M. Hall. "Combustion phasing modeling and control for compression ignition engines with high dilution and boost levels." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 7 (August 1, 2018): 1834–50. http://dx.doi.org/10.1177/0954407018790176.

Full text

Abstract:

Because fuel efficiency is significantly affected by the timing of combustion in internal combustion engines, accurate control of combustion phasing is critical. In this paper, a nonlinear combustion phasing model is introduced and calibrated, and both a feedforward model–based control strategy and an adaptive model–based control strategy are investigated for combustion phasing control. The combustion phasing model combines a knock integral model, burn duration model, and a Wiebe function to predict the combustion phasing of a diesel engine. This model is simplified to be more suitable for combustion phasing control and is calibrated and validated using simulations and experimental data that include conditions with high exhaust gas recirculation fractions and high boost levels. Based on this model, an adaptive nonlinear model–based controller is designed for closed-loop control, and a feedforward model–based controller is designed for open-loop control. These two control approaches were tested in simulations. The simulation results show that during transient changes, the CA50 (the crank angle at which 50% of the mass of fuel has burned) can reach steady state in no more than five cycles and the steady-state errors are less than ±0.1 crank angle degree for adaptive control and less than ±0.5 crank angle degree for feedforward model–based control.

APA, Harvard, Vancouver, ISO, and other styles

50

Dawei, Pi, Kong Zhenxing, Wang Xianhui, Wang Hongliang, and Chen Shan. "Design and experimental validation of control algorithm for vehicle hydraulic active stabilizer bar system." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 5 (May 14, 2018): 1280–95. http://dx.doi.org/10.1177/0954407018770539.

Full text

Abstract:

This paper presents a novel active roll control algorithm for vehicle hydraulic active stabilizer bar system. The mechanical structure and control scheme of hydraulic active stabilizer bar system is detailed. The anti-roll torque controller is designed with “Proportional-Integral-Differential (PID) + feedforward” algorithm to calculate the total anti-roll torque. A lateral acceleration gain and roll rate damping are added into “PID + feedforward” controller, which can improve vehicle roll dynamic response. The torque distributor is introduced based on fuzzy–PID algorithm to distribute the anti-roll torque of front and rear stabilizer bar dynamically, which can improve vehicle yaw dynamics response. The actuator controller is used for realizing the closed-loop control of the actuators displacement and generating the accurate anti-roll torque. The hardware-in-the-loop simulation platform is established based on AutoBox and active stabilizer bar actuators. The hardware-in-the-loop experiment is carried out under typical maneuvers. Experimental results show that the proposed control algorithm improves the vehicle roll and yaw dynamics response, which can enhance the vehicle roll stability, yaw stability, and ride comfort.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Feedforward control loop'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles