Speed control of dc shunt motor your electrical guide. This is because speed is inversely proportional to the field flux. Jan 17, 2018 speed control of d c shunt motor by field current and armature voltage control method. Motors plays an important role in energy conversion process. Most dc motors are operated in the knee region to prevent any fluctuation in speed during voltage sagswells and other minor disturbances. As demonstrated in the previous lab, the shunt winding produces an almost constant speed of operation low speed regulation.
You can sense the effect of speed control of dc motor in the movement of robotic vehicles, movement in elevators, movement in paper mils and so on when different types of dc motors. In the above experiment, does the saturation in the machine play any role. To obtain the armature voltage vs armature current load curve of the generator. To study the properties of the separatelyexcited dc shunt generator under noload and fullload conditions 2. We shall use the same dc motor for which the parameters were calculated in the previous experiment. Speed control methods of dc motor speed control of shunt motor 1. A rheostat is connected in series with armature winding. The voltage equation of a dc motor is where e b is the back emf, v is the supply voltage, i a the armature current, and r a is the armature resistance again, the expression of back emf in a dc motor is where. A mathematical model of the process has been developed using real plant data and then conventional controllers and fuzzy logic controller has been designed. List of requirementsequipmentexperimental panel system unit w 1. Data for speed control of a shunt dc motor using alternating armature resistance.
Conclusion in this lab experiment the dc motor speed control. Speed control of dc motor shunt motor and series motor. Discussion a dc motorgenerator can run either as a motor or as a generator. The terminal voltage of the armature, v the external resistance in armature circuit, r a the flux per pole. As resistance increased, the value of the field current will reduce.
Therefore speed of the 3 types of dc motors shunt, series and compound can be controlled by changing the quantities on the righthand side of the equation above hence the speed can be varied by changing. In this experiment the mechanical characteristics b and j will be determined. Starting and reversing of dc shunt motor labappara. In order for a dc motor to run, current mu st flow in the armature winding and the stator must develop a magnetic field flux, either by means of a shunt winding or a series winding or both. Nvis 7008 dc machine labii is an important system for the electrical laboratories. Ee 448 laboratory experiment 4 introduction to dc motors 4 assuming shunt connected dc motor, compute back emf, field resistance, armature resistance, field loss, armature loss, power efficiency, starting torque, and noload speed. Experiment 5 dc motor speed control walter scott, jr. The machine used in this experiment is a representative of an industrial dc motor or generator with a rated power of tens of kilowatts. The voltage equation of a dc motor is where e b is the back emf, v is the supply voltage, i a the armature current, and r a is the armature resistance.
It is a machine which converts electrical energy into mechanical energy. Automatic speed controller of a dc motor using arduino. Dec 29, 2015 the shunt field windings of a dc shunt motor are made of smaller gauge wire, but they have many more turns than a serieswound dc motor. Jun 12, 2019 before discussing the speed control of dc motor, let us first establish the expression of the speed of a dc motor. Variations of speed with armature voltage control at constant field current. The armature of the shunt motor m whose speed is to be controlled is connected directly to a d. View notes speed control of dc shunt motor from boston 6. As such, the field windings and armature are connected in a parallel combination, and in electrical terminology a parallel combination is known as a shunt. The torque developed by a dc motor is directly proportional to the armature current and the stator flux. Brake test is also a method of finding efficiency of dc motors.
Electrical machines for mechatronics laboratory 7 4 speed control of series dc motors unlike with the shunt dc motor, there is only one efficient way to change the speed a series dc motor. The field of the shunt motor is supplied from a constantvoltage exciter e. Introduction to dc motors 1 ee 448 lab experiment no. Dc motor speed control in matlab the engineering projects. Jan 29, 2017 this video teach you to understand the speed control method of dc shunt motor with practical demonstration. Jul 11, 2019 speed control of a dc motor is either done manually by the operator or by means of an automatic control device. Variation of speed with variation of field current at constant voltage. The supply is switched off after experiment is over. Experimental facts should always be given in the past tense. Speed control of d c shunt motor by field current and armature voltage control method. The high number of turns allows a strong magnetic field to be generated, but the smaller gauge wires provide a high resistance and limit the current flowing through the shunt coil. Here, in this tutorial i will explain about how can make a program for dc motor speed control in matlab by creating a gui having different buttons on it to control the direction of rotation of the dc motor as well as the speed of the dc motor by sending different commands through the serial port. Title of the experiment page no 7 retardation test on dc shunt motor.
In an open loop control, the only components in the system. To control the speed of dc shunt motor using armature control method. To determine the load characteristics of dc shunt motor. Armature voltage with field current constant is plotted on a graph paper. Speed control of dc motor full guide for controlling the. Dec 01, 2014 this paper describes the speed control of a dc shunt motor using conventional controllers pid, imc and fuzzy logic controller based on matlab simulation program. The set up for speed control of dc shunt motor by armature voltage control method is shown in the figure. Automatic speed controller of a dc motor using arduino, for. Therefore the voltage drops i a r a will be negligible as compared to the external supply voltage v. Dc machine labii experiment electrical training lab.
To study the speed control of the given dc shunt motor by field control method and armature control method. Performance of dc motors experiment 2 linkedin slideshare. To discover the characteristic change in speed of a dc shunt motor as it is loaded. The purpose of this experiment is to design and implement a closeloop speed control of a dc motor drive. In a shunt motor, the field winding, as we ll as the armature winding, is connected in. Armature resistance control and field flux control the dc motor converts the mechanical power into dc electrical power. The series dc motor behaves differently than the shunt dc motor. This paper describes the speed control of a dc shunt motor using conventional controllers pid, imc and fuzzy logic controller based on matlab simulation program. C shunt motor as a function of armature voltage, field current, and external resistance in the armature circuit. Since they are connected in parallel, the armature and field windings are exposed to the same supply voltage. Speed control of dc shunt motor electric motor direct current.
View notes speedcontrolofdcshuntmotor from boston 6. A dc shunt motor also known as a shunt wound dc motor is a type of selfexcited dc motor where the field windings are shunted to or are connected in parallel to the armature winding of the motor. Though there are separate branches for the flow of armature current and field current. Electrical machines for mechatronics laboratory 6 5 if a ra. There are two types of controls which were made in order to control the speed as. To study the methods of controlling the speed of shunt dc motor. To study the variation of speed of a dc shunt motor. Apparatus type range quantity 1 voltmeter mc 0300v 1 2 ammeter mc 020a 1 3 rheostat 1250.
Below in summary charts torque to duty cycle are presented in the cases scenarios. Working principle from the above circuit diagram, we can conclude that if we want to increase the speed of the shunt motor, we will vary the field resistance. In experiment3 and 4, the speed of the dcmotor was controlled by using an openloop voltage control. Speed control of dc shunt motor with field and armature rheostat control 79 2. In this article we are going to discuss about brake test on d. In dc shunt motor experiment does the saturation in the. We shall use the same dcmotor for which the parameters were calculated in. This product provides comprehensive learning of functioning of a dc motor. It can aptly be employed for per forming various exercises like motor star ting, speed control, ni characteristics etc. Since the most basic requirement of a motor is that it should rotate at the desired speed, we will require that. To interpret the load characteristics of a dc shunt motor. That method is to change the terminal voltage of the motor. K e b o where, kconstant this shows the speed of a dc motor is directly proportional to the back emf and inversely proportional to the flux per pole. The series winding produces a machine with very high speed regulation.
There are two types of controls which were made in order to control the speed as well as the current. To study the speed control of a dc shunt motor by the following methods. Jul 11, 2019 a dc shunt motor also known as a shunt wound dc motor is a type of selfexcited dc motor where the field windings are shunted to or are connected in parallel to the armature winding of the motor. The concept of the speed regulation is different from the speed control. Discussion a dc motor generator can run either as a motor or as a generator. Before discussing the speed control of dc motor, let us first establish the expression of the speed of a dc motor. The dc motor converts the mechanical power into dc electrical power. In experiment 3 and 4, the speed of the dc motor was controlled by using an openloop voltage control. This lab allowed us to further investigate the characteristics of the various dc motor speed control schemes. Towards to establish speed control, many tested have been taken place. Therefore speed of the 3 types of dc motors shunt, series and compound can be controlled by changing the quantities on the righthand. Conclusion in this lab experiment the dc motor speed. First consider that our uncompensated motor rotates at 0.
In experiment3 and 4, the speed of the dc motor was controlled by using an openloop voltage control. Thus the product makes the subject completely understandable. Speed control of dc shunt motor with field and armature. The shunt field windings of a dc shunt motor are made of smaller gauge wire, but they have many more turns than a serieswound dc motor. Electrical machinel dc laboratory manual grietelectrical and. Experiment no 1 speed control of dc motor and 3ph induction motor.
By varying the value of r we can vary the voltage across the armature. Because loading will be applied directly on shaft of the motor by means of a belt and pulley arrangement. This is different to speed regulation where the speed is trying to be maintained or regulated against the natural change in speed due to a change in the load on the shaft. To control the speed of dc shunt motor using field control method. A comparative analysis of performance evaluation of all controllers has.
Try to verify the torquespeed equation derived earlier in this writeup for 3 or 4 values of. In this lab experiment, the dc motor speed control was studied. Speed control of dc motor shunt type aim a to study the speed control of dc motor below the normal range by armature resistance control and to plot speed vs armature voltage, characteristic. Brake test also called as direct loading test of testing the motor. Speed control methods of dc motor shunt, series motors.
In this experiment the simple rectifier supply, used in experiment 2 for the armature of the motor. One of the most important features of the dc motor is that their speed can easily be control according to the requirement by using simple methods. Maintain constant armature voltage through out the experiment. Speed control of a dc motor using controllers science. Live demonstration of speed control in dc shunt motor, electrical machines lab. Speed control of dc shunt motor with field and armature rheostat. Can you get speeds below rated speed by field control method. Before discussing the speed control of dc shunt motor, we have to find the factors affecting the speed of a dc motor. The motor shaft should start rotating in the desired direction. To control the speed of dc shunt motor by armature control method and field control method apparatus requirred. The purpose of this experiment is to design and implement a closeloop speed control of a dcmotor drive. Assuming stator flux to be linear function of field current, determine the constant kk f. Speed control of dc motor is the most important feature we interest in, when we control the speed we vary it according to the requirements and the operation we need. Speedcontrolofdcshuntmotor page 1 experiment no 9 aim.
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