Proportional control

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

Design of PI Controller in Pitch Control of Wind Turbine: A Comparison of PSO and PS Algorithm

Abstract: In wind energy conversion system (WECS) at wind speed above rated, the pitch angle is controlled to keep the generated output fixed so also the speed and the frequency. The model is built as a discrete model of WECS connected to Grid including a Line to Ground (LG) fault in Grid. A Proportional-Integral (PI) controller with gain K p and K i is used in pitch angle control loop. The proportional gain K p and integral gain K i are tuned through Particle Swarm Optimization (PSO) and Pattern Search (PS) algorithms. A comparison of two different objective functions with its weight adjustment is presented. The performances of the algorithms in designing the optimal controller are compared. The analysis indicates the superiority of PSO over PS and takes less time to achieve the minimum error criteria. The controller designed using PSO minimizing the proposed objective function has better settling time as regards wind turbine speed response, compared to the other. The control action is validated in real time using OPAL-RT taking different cases of random wind speed, gust and gust with random wind speed and Line to Ground fault.

A graphical approach to hydrogenerator governor tuning

Abstract: A graphical approach to hydrogenerator governor tuning is described. A graph which is developed can be used to predict optimum proportional and integral gains based on four parameters: the time constants of the water column and of the rotor inertia, and the self-regulation constants of the turbine and of the loading grid. The pole cancellation method of design is used, and the results are posed in an easy-to-use format that does not require the solution of systems of equations. Information on stability limits and comparisons with other work are included. >

Expert System Architecture for Control System Design

Abstract: This paper describes the development of an expert planning framework for design of control systems. The expert planner incorporates the knowledge of a control system designer in selecting and applying mathematical algorithms from several branches of control theory such as Kalman filter design, proportional/integral/ derivative control, and optimal state feedback. The framework has been developed directly in Lisp rather than using any of the available domain-independent expert system frameworks. The planning is done at two levels: a high level that uses general rules about control system design and a low level that uses rules about the use of a computer aided control system design (CACSD) package. The system has been implemented and demonstrated on a Xerox 1100 Lisp workstation controlling a CACSD package running on a VAX 11/780, designing a servo (command tracking) control system for aircraft.

On the Stabilizing PID Controllers for Integral Processes

Abstract: In this note, we show how to determine the set of stabilizing parameters of a proportional-integral-derivative controller for an integrator plus dead time process. In particular, by exploiting a version of the Hermite-Biehler theorem applicable to quasipolynomals, the admissible range of the proportional gain is computed first. Then, for each value of the proportional gain in that range, the set of stabilizing values of the integral and derivative gain are found. It is shown that the procedure is greatly simplified with respect to the case of a second-order integral process with dead time.

Direct torque control with feedback linearization for induction motor drives

Abstract: This paper describes a Direct Torque Controlled (DTC) Induction Machine (IM) drive that employs feedback linearization and sliding-mode control. A feedback linearization approach is investigated, which yields a decoupled linear IM model with two state variables: torque and stator flux magnitude. This intuitive linear model is used to implement a DTC type controller that preserves all DTC advantages and eliminates its main drawback, the flux and torque ripple. Robust, fast, and ripple-free control is achieved by using Variable Structure Control (VSC) with proportional control in the vicinity of the sliding surface. The VSC component assures robustness as in DTC, while the proportional component eliminates the torque and flux ripple. The torque time response is similar to DTC and the proposed solution is flexible and highly tunable due to the proportional controller. The controller design and its robust stability analysis are presented. The sliding controller is compared with a linear DTC scheme, and experimental results for a sensorless IM drive validate the proposed solution.