Types of dc motors separately excited motor shunt excited motor series excited motor compound excited motor permanent magnet pm motor. C shunt motor is conducted and its performance curves are drawn. Working principle of dc shunt motor, dc series motor and all other dc motors can be stated as follows. C shunt, ii separately excited and iii series motor widely used are given at the beginning. The input to the motor is given by the supply mains. Hopkinsons test of dc machine premier hopkinsons test of dc machine is an adaptable training system for electrical laboratory.
Working principle of dc shunt motor your electrical guide. A dc shunt motor 50hp, 250v is connected to a 230v supply and delivers power to a load drawing an armature current of 200a and running at a speed of 1200rpm, given ra0. Dc motors concepts dc motors 1 noload speed of which of. Brake test on dc shunt motor electric motor electrical engineering. The resistances of the armature and shunt field are 0. One machine runs normally as a motor and drives generator whose output is wasted in a variable load r fig. This paper discusses the speed and torque control of a shunt dc motor through matlab simulink simulations. Direct method of testing of dc machine, also known as brake test if carried out for a dc motor will be discussed in this post.
Speed control of dc shunt motor with field and armature rheostat control 79 2. Hopkinsons test hopkinsons test is also known as regenerative test, back to back test and heat run test. Since they are connected in parallel, the armature. Dc shunt motor speed control and analysis using ziegler nichols algorithm with pid controller yogesh sharma l,a shis patra 2 1, 2 electrical engineering department, m. Consequently, shunt motor will not usually run on a. To study the behavior of a shunt dc motor speed when a. To determine the efficiency of the given dc shunt motor by conducting load test. Dc shunt motor speed control and analysis using ziegler. Hugh d young explains torque is the propensity of force to cause a rotational motion, and here in dc motor the torque develops between the armature and the stator, and its given by the product of the force and the radius at which the force acts. And the armature winding is connected to external supply voltage hence it plays the role of current carrying conductor.
To conduct the no load test on the dc shunt motor and determine its. Speedcontrolofdcshuntmotor page 1 experiment no 9 aim to study the speed control of d. This is the complete theory of brake test on dc shunt motor including laboratory manual. Dc motors although ac motors are used in most of the cases, dc motors have many applications and used for multipurpose applications. One is acting as a motor and another one as a generator. Mathematical modeling of dc shunt motor dc shunt motors have the field coil in parallel shunt with the armature. In this test the efficiency of the machine at any load is predetermined. It is an attempt to explain the experiment of load test on dc shunt motor in tamil by dr. Hopkinsons test of dc machine premier engineering lab.
To perform the brake test on the given dc compound motor and to obtain the. The shunt motor runs at a speed defined by the expressions. To conduct load test on dc shunt motor and to find efficiency. By means of this method, the motor can be worked at any speed up to its maximum speed. Its operation is based on the principle that when a current carrying conductor is placed in a. To select the motor type, rightclick on the electric motor block, select variantoverride using and then the desired motor. In a shunt dc motor, the armature and field windings are connected in parallel.
Brake test on dc shunt motor free download as word doc. Hence dc shunt motors are typically used applications that require five or more horse power 8. If a dc generator delivers 180 w to a load, what is. Download as docx, pdf, txt or read online from scribd. The voltage applied to the motor may be reversed by backing the field current of generator through controller fc. On occasion, a field regulator is contained within the field circuit of dc shunt motor for additional speed adjustment. Experiment 6 shunt dc motor ii objective to study the behavior of a shunt dc motor speed when the field resistance is altered. To obtain the performance characteristics of a dc shunt motor by load test. Brake test on dc shunt motor electric motor electrical. What is a dc shunt motor and its advantage and disadvantage. C is applied to a shunt motor, the large inductive reactance of shunt winding will reduce the field current too much. In this post, we will discuss about various speed control methods of dc shunt motor. The field current lf is obtained from an external independent dc source. Ee 448 laboratory experiment 4 introduction to dc motors 2.
Theory the efficiency of the dc machine can be accurately determined by the regenerative method, normally known as hopkinsons test. Dc motors concepts dc motors 1 noload speed of which of the following will be highest a shunt motor b series motor c cumulative compound motor d. Load test on dc shunt motor offered by unicon instruments, a leading supplier of dc shunt motor in sadar bazar, ambala, haryana. Dc machines can be tested by three different methods namely direct method, indirect method and regenerative method. The shunt winding has a large number of turns so that it has appreciable inductance. Fields test for series motor this test is applicable to two similar series motors. Scribd is the worlds largest social reading and publishing site. Shunt motor with electrical and torque characteristics.
This test overcomes the drawback of swinburnes test, which. The regulation of a 3phase alternator may be predetermined by conducting the open. Speed control of dc shunt motor with comparative analysis. Dc motor principle a machine that converts dc power into mechanical energy is known as dc motor. C of a dc shunt generator and to determine its critical. Swinburnes test method for testing dc shunt motor for a d. Brake test in one of the most simple way of finding efficiency of any kind of dc machine. E b vi a r a here, eb back emf, in volts ia armature current, in amps ra armature resistance, in ohms v terminal voltage, in volts. There are 3 main types of dc motor that are available. The load characteristics curve of dc series generator. A machine that converts dc electrical power into mechanical power is known as dc motor. According to stephen and dale, 2009 the field coils of a series motor has a low resistance consisting of few turns of large diameter coils of wire while the field coils of the shunt motor has a high resistance made up of.
Test of dc shunt motor configuration psychology essay. Swinburnes test is the most commonly used and simplest method of testing of shunt and compound wound dc machines which have constant flux. Now close switch s1 and slowly increase the voltage supplied to 3phase induction motor using autotransformer until it rotates at the rated speed of dc machine. The current in the field coil and the armature are independent of one another. Brake drum should be cooled with water when it is under load. Dc machine efficiency by direct loading,efficiency formula in brake test on dc series,shunt,compound motors. In electrical terminology, a parallel connection is termed shunt. You should remember from basic electrical theory that a parallel circuit is often referred to as a shunt. We can run the machine as a motor or as a generator. As the constant loss is known the efficiency can be predetermined at any load. In the case of a dc motor, the magnetic field is produced by the field winding. Speed control of dc shunt motor with field and armature. When a current carrying conductor is placed in a magnetic field, it experiences a force.
The open circuit characteristics for a dc generator are determined as follows. Geethanjali college of engineering and technology department electrical and electronics engineering list of experiments s. Determination of critical field resistance critical speed. It is a direct method and consists of applying a brake to a. Several paragraphs that explain the motivation of the. The brake test is the one kind of load test on dc shunt motor. Parts and principle of operation of a shunt dc motor.
Introduction to dc motors 1 ee 448 lab experiment no. Riosque y zack special edition hd recommended for you. It is designed to demonstrate the fundamental concepts and also facilitates easy learning about two similar machines are required to carry out hopkinsons test. The company was incorporated in 1954 and is registered with indiamart. 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. Schematic diagram for hopkinsons test on dc machine. As the test is on noload, it is impossible to know whether commutation would be satisfactory at fullload and whether the temperature rise would be within the specified limits. This type of winding is called shunt winding and the motor shunt dc motor. In hopkinson test, two identical shunt machines are required which are coupled both mechanically and electrically in parallel.
A comparison of the torquespeed characteristics for five different motor types. All motors have been sized for roughly the same mechanical power rating. Electrical machinel dc laboratory manual grietelectrical and. Consider the air gap flux remains fixed at its value at no load. Generally, this test can be done for the low rated dc machines.
Series motors which are mainly used for traction work are easily available in pairs. The main advantages of the swinburnes test are as follows. To draw the performance characteristics of the given dc shunt motor by conducting load test. Thus, this method is an economical and convenient method of testing of dc machines. The lab is equipped with dc seriesshunt motor, compound motor, universal. Just like most energy conversion devices, the dc shunt motor is not 100% efficient. To study the behavior of a shunt dc motor speed when the armature voltage is altered. The power required to test a large machine is small.
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. Speed control methods of dc shunt motor my tech info. State two ways by which the output polarity of a separatelyexcited dc shunt generator can be changed 2. Pdf laboratory manual electrical machines ayyappa javangula. The dc shunt motor is 120vdc with rated speed of 1800 revolutions per minute. 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. If the field of a dc shunt motor gets opened while motor is running a. 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.
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