SERVO CONTROL SYSTEMS 1: DC Servomechanisms
Elke Laubwald: Visiting Consultant, control uk
ABSTRACT: This is one of a ries of white papers on systems modelling, analysis and control, prepared by Control Systems牛肉炒饭的做法
uk to give insights into important principles and process in control. In control systems there are a number of generic systems and methods which are encountered in all areas of industry antechnology. The white papers aim to explain the important systems and methodsinstraightforward terms.
The white papers describe what makes a particular type of system/method important, how it works and then demonstrates how to control it. The control demonstrations is performed using models of real systems designed by our founder - Peter Wellstead, and developed for manufacture by TQ Education and Training Ltd in their CE range of equipment. Where possible results from the real system are shown. This white paper is about the universally ud ‘work hor’ of electro-mechanical systems– the DC rvo c
ontrol system or rvomechanism.
1. What is a Servo Control System and rvo motor?
A rvo control system is one of the most important and widely ud forms of control system. Any machine or piece of equipment that has rotating parts will contain one or more rvo control systems. The job of the control system may include:
Maintaining the speed of a motor within certain limits, even when the load on the output of the motormight vary. This is called regulation.
Varying the speed of a motor and load according to an externally t programme of values. This is called t point (or reference) tracking.
Our daily lives depend upon rvo controllers. Anywhere that there is an electric motor there will be a rvo control system to control it. Servo control is very important. The economy of the world dependsupon rvo control (there are other things to be sure – but stay with me on the control theme). Manufacturing industry would cea without rvo sy
stems becau factory production lines could not becontrolled, transportation would halt becau electric traction units would fail, computers would cea becau disk drives would not work properly and communications networks would fail becau network rvers u hard disk drives. Young people would become even more unbearable and they would complain more than they do now, becau their music and games systems will not work without rvo control.
Servo control systems are that important and it is vital to know about them. So pay attention and sit up straight – you are not on holiday and I am not writing this for the good of my health.
Also known as the implementation of the motor rvo motor, the automatic control system for the implementation of components to convert signals received from the motor shaft angular displacement or angular velocity output.DC and AC rvo motor is divided into two categories, the main feature is that when the signal voltage is zero, no rotation of the phenomenon, the increasing speed with uniform torque decread.Servo motors to contr
ol mechanical rvo system in the operation of the engine components. Is a rvomotors device.Servo motor can control the speed, position accuracy is very accurate.The voltage signal into a torque and speed to drive the control object.Rotor speed by the input signal control, and can respond rapidly, in the automatic control system for the implementation of components, and has electrical and mechanical time constant, linear and high initiating voltage low.
2. Modelling a Simple Servo System
Before we can control a system we must understand in mathematical terms how the system behaves without control. This is system modelling and it is a fundamental part of our work in control systems analysis. This white paper is about the simplest form of rvo – the direct current (DC) position control rvomechanism. It is important becau, although it is the simplest form of rvomechanism, it is udas the starting point for understanding all other rvo systems The basic form of a DC rvo system is made of an electric motor with an output shaft that has an inertialload J on it, and friction in the be
arings of the motor and load (reprented by the constant b). There will be an electric drive circuit where an input voltage u(t) is transformed by the motor into a torque T(t) inthe motor output shaft. Using systems modelling ideas for mechanical systems a torque balance can bewritten between the input torque from the motor and the torque required to accelerate the load and overcome friction. Th生日会邀请函
is is shown in the equation
