مقاله انگلیسی کنترل همزمان سرعت و شار میدانی موتورهای غیرخطی DC
Introduction
Nonlinear Mathematical Model of the Separately Excited Direct Current Motor
Main Result
Implementation of Controller
Conclusion
Abstract
This paper presents a novel strategy that exploits the properties presented by the nonlinear model of direct current motors, to obtain simultaneously the required control voltages in the armature and in the field windings when velocity and magnetic flux are considered as reference inputs. In this scheme, it is considered that the current signals for both windings are available, as well as the signal of the angular position. So by means of a second order filter, the signal that takes the place of the angular velocity is obtained. By using the Lyapunov stability theory, stability of the closed loop system, global convergence of angular velocity and field flux is concluded, moreover all the states variables are bounded for all initial conditions. Experimental tests confirm the theoretical proposal; that is, global asymptotic tracking of the angular velocity and field flux is ensured. The equations of this proposal are physically implementable and due to the structure of the control scheme, the voltages of both windings can be tuned in such a way that less current dissipates, resulting in energy saving and having the same response of velocity. Index Terms—Field Flux, Nonlinear Model, Passivity, Second Order Filter, Stability Analysis.
INTRODUCTION
T HE Direct Current (DC) motors are still considered as the usual option, when a system is controlled for a wide range of velocities, because of its excellent operational properties and control characteristics. Effectively, the DC machine was widely used for a long time in adjustable velocity drives, but due to the strong development of power electronics technologies and control theory applied to AC machines, the DC machines are being relegated in certain areas, but in many traditional industries are still used [1]. In high-performance motion applications, such as in robotic manipulator position tracking, machine tool manufacturing, high-speed industrial automation, etc., there is the need for accurate, positioning and / or speed control. To achieve the latter, many systems continue to use DC motors to perform mechanical traction, so some inherent problems in these task still present challenges to solved when considering one or more control performance specifications (e.g., tracking trajectories of reference, rejection of disturbances, robustness,