Proportional control

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

PID controller tuning using multi-objective optimization based on fused Genetic-Immune algorithm and Immune feedback mechanism

Abstract: In this paper, a Genetic-AIS (Artificial Immune System) algorithm is introduced for PID (Proportional-Integral-Derivative) controller tuning using a multi-objective optimization framework. This hybrid Genetic-AIS technique is faster and accurate compared to each individual Genetic or AIS approach. The auto-tuned PID algorithm is then fused in an Immune feedback law based on a nonlinear proportional gain to realize a new PID controller. Immune algorithm presents a promising scheme due to its interesting features such as diversity, distributed computation, adaptation and self monitoring. Accordingly, this leads to a more effective Immune-based tuning than the conventional PID tuning schemes benefiting a multi-objective optimization prospective. Integration of Genetic-AIS algorithm with Immune feedback mechanism results into a robust PID controller which is ultimately evaluated via simulation control test scenarios to demonstrate quick response, good robustness, and satisfactory overshoot and disturbance rejection characteristics.

Stability analysis of variable-structured PI controller by fuzzy logic for servo system

Abstract: The authors propose a variable structure PI (proportional plus integral) controller whose structure is continuously varied by fuzzy logic such that a proportional controller dominates the integral controller if the absolute value of the error is large and vice versa in order to obtain a high-performance controller (with quick time response and without overshoot) Then it is applied to servo motor speed control The global and asymptotic stability of the overall control system is proved by using the Lyapunov stability theorem >

A system for controlling a hydraulic cooling fan for an engine as a _function of ambient and coolant temperatures

Abstract: An automatic actuator system for a cooling fan of an internal combustion engine comprising a first detector for detecting the temperature of the cooling water in a cooling system for the engine and a second detector for detecting the atmospheric temperature. An electrical control circuit generates a first control signal corresponding to the cooling water temperature detected by the first detector and a second control signal corresponding to the maximum number of revolutions of the cooling fan as a function of atmospheric temperature detected by the second detector and generates an electrical output signal corresponding to the difference between the first and second control signals. A proportional control valve is coupled to the control circuit and controlled by the output signal of the control curcuit, and a cooling fan driving device is coupled to the control valve, wherein the rotational speed of the fan driving device is controlled as a function of the flow rate of fluid controlled by the proportional control valve.

ABR traffic control over multi-source single-bottleneck ATM networks

Abstract: The problem of flow control in fast, connection-oriented communication networks supporting the traffic generated by multiple sources is considered. A novel sampled time strategy governing the behaviour of the sources is proposed. The strategy combines the Smith principle with the conventional sampled time proportional controller. It guarantees an equal resource allocation between various users, full bottleneck link utilisation and no cell loss in the controlled network. Consequently, the need for cell retransmission is eliminated and a high throughput is ensured. Furthermore, transmission rates generated by the algorithm are limited. This property permits a direct implementation of the proposed strategy in the network environment. A simulation example confirms favourable performances of the proposed control scheme.

On combining slewing and vibration control in flexible manipulators via singular perturbations

Abstract: The problem of designing a composite control as a strategy for controlling flexible link manipulators is addressed. The composite control consists of a slew control based on the reduced order model to achieve the desired slewing of the robot links and a fast control based on a manifold condition whose purpose is to dampen the link vibrations. The slow control is a decentralized torque control which approximately linearizes the reduced order model and adds a PI (proportional integral) control term for trajectory tracking. The fast control is a distributed actuator which consists of a thin piezoelectrically active film that when applied with a voltage produces a strain that dampens flexural vibrations. The control design is based upon a distributed parameter model of a two-link flexible manipulator. Computer results using a finite dimensional model obtained via modal expansion are presented to illustrate the control strategy. >