scispace - formally typeset
Search or ask a question
Topic

Proportional control

About: Proportional control is a research topic. Over the lifetime, 3756 publications have been published within this topic receiving 49050 citations.


Papers
More filters
Proceedings ArticleDOI
01 Jan 2005
TL;DR: In this paper, a feedback control of manipulator using machine vision was proposed to measure the distance of the fruit from the camera, and the laser ranging sensor was used to locate the fruit in the center of the image.
Abstract: The challenges in developing a fruit harvesting robot are recognizing the fruit in the foliage, detaching the fruit from the tree, and the coordination of the vision system and the hand system. This paper presents the development of a feedback control of manipulator using machine vision. To measure the distance of the fruit from the camera, the laser ranging sensor is used. The detected fruit should be in the center of the image for its distance to be measured, so the camera should be positioned using the manipulator to position the fruit in the center of the image. A feedback control using machine vision is used for this positioning procedure. Two controllers are considered; threeposition on-off controller and proportional controller with variable gain. Both controllers were implemented in a simulation. Simulation results showed that both controllers were able to guide the manipulator to position the fruit in the center of the image.

21 citations

Journal ArticleDOI
TL;DR: In this article, a hybrid neural control scheme for building services control is described, which is capable of compensating for plant static nonlinearities and of adapting on-line to degradation in the plant, avoiding the instability problems that can arise when neural networks are introduced into the feedback control loop.
Abstract: The unsatisfactory performance of conventional building services controls is frequently due to poor commissioning, and to the inability of conventional controllers to deal with non-linearities and to adapt to long-term changes in the behaviour of the plant. The paper describes a hybrid neural control scheme which is capable of compensating for plant static non-linearities and of adapting on-line to degradation in the plant, but avoids the instability problems that can arise when neural networks are introduced into the feedback control loop. The hybrid controller uses a neural network, which learns the non-linear static characteristics of the plant, to generate feed-forward control action, and a conventional proportional controller, acting as a feedback trimmer, to deal with unmeasured disturbances. Results of a detailed computer simulation of a heater battery are presented; these show that the hybrid scheme can produce more consistent control, and is less sensitive than a conventional PI algorithm to init...

21 citations

Proceedings ArticleDOI
16 May 2008
TL;DR: In this article, the authors proposed a new test equipment for single-phase ac power source tests named PEL(power electronic load), the proposed architecture consists of two power stages such as input AC-DC imitation converter to imitate various loads and the output grid-connection converter to send back the recycling energy to the utility grid.
Abstract: The paper present a new test equipment for single-phase ac power source tests named PEL(power electronic load), the proposed architecture consists of two power stages such as input AC-DC imitation converter to imitate various loads and the output grid-connection converter to send back the recycling energy to the utility grid. In PEL, the controllable imitation converter enlarges the load bound that can be imitated, make the system more flexible, it even can simulate the nonlinear load to verify the stability of the tested ac power; and the grid-connection transformer ensures the system operate in security. A simple control scheme based on P(proportion) and PI(proportion and integral) control is proposed to ensure the system operate normally. But the phase delays in the digital control system and the controlled plant, the change of the parameter in the PEL, the unpredictable disturbances in the system will degrade the effectiveness of the simple control scheme. The repetitive control is proposed to solve the problem, it can ensure the system with excellent steady characteristics, to remedy the shortage of the repetitive controller in dynamic characteristics, the traditional P controller is connected with it in parallel connection, the compound controller acts well both in steady state and dynamic state, it even can hold a perfect effect in simulating the nonlinear load. The paper analyzes the repetitive controller in details. At last, the simulation and experimental results are provided to testify the effectiveness of the proposed control scheme.

21 citations

Journal ArticleDOI
TL;DR: An extended optimal torque controller is designed based on effective wind speed estimation to control the variable-speed wind turbine using multilayer perceptron based nonlinear input-output mapping for approximating the nonlinear aerodynamics of the wind turbine.
Abstract: Most variable-speed wind turbines employ advanced control scheme to improve their performance. In this paper, an extended optimal torque controller is designed based on effective wind speed estimation to control the variable-speed wind turbine. To do this, multilayer perceptron based nonlinear input-output mapping is firstly used for approximating the nonlinear aerodynamics of the wind turbine. In other words, based on this nonlinear mapping, effective wind speed is estimated from the measured rotor speed, the measured pitch angle, and the observed aerodynamic torque by the disturbance observer. After that, the optimal rotor speed command for capturing maximum wind energy is derived from the estimated effective wind speed. And then the optimal torque command is calculated by combing the standard optimal torque formula and a proportional control loop that is added to effectively reduce the moment of inertia. At last, some simulation results are validated to display the availability of the improved effective wind speed estimation algorithm and control strategy. Moreover, the corresponding simulation results indicate that compared with the existing methods, the proposed method increases the accuracy of the effective wind speed estimation by 2-7% and the energy production efficiency by 0.35%.

21 citations

Journal ArticleDOI
TL;DR: In this paper, a one degree-of-freedom (DoF) mechanical system with low viscous damping is subjected to proportional-derivative (PD) force control, and analytical results are presented in the form of stability charts in the parameter space of sampling time, control gains and mechanical parameters.
Abstract: The paper presents an analytical investigation of the dynamics of digital force control. A one degree-of-freedom (DoF) mechanical system with low viscous damping is subjected to proportional–derivative (PD) force control. Analytical results are presented in the form of stability charts in the parameter space of sampling time, control gains and mechanical parameters. Simple closed form results include the largest stable proportional gain and the least steady state force error that provide synthesis of mechanical and control system parameter influences for the design of digital force control. Also, a novel analytical explanation is given why even the properly filtered force derivative signal is rarely used in practice, and why the occurring vibrations have frequencies one range smaller than that of the sampling frequency of the digital control.

21 citations


Network Information
Related Topics (5)
Control theory
299.6K papers, 3.1M citations
93% related
Control system
129K papers, 1.5M citations
92% related
Robustness (computer science)
94.7K papers, 1.6M citations
85% related
Optimization problem
96.4K papers, 2.1M citations
80% related
Electric power system
133K papers, 1.7M citations
80% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20237
202217
202162
2020110
2019150
2018150