You need to power the field and armature separately. We shall use the same dc motor for which the parameters were calculated in the previous experiment. Factors controlling motor speed it has been shown earlier that the speed of a motor is given by the relation it is obvious that the speed can be controlled by varying i fluxpole, f flux control ii resistance ra of armature circuit rheostatic control and iii applied voltage v voltage con trol. This paper discusses the speed and torque control of a shunt dc motor through matlab simulink simulations. To study the behavior of a shunt dc motor speed when the armature voltage is altered. Experiment 5 dc motor speed control walter scott, jr. As you know that the construction of any type of dc motor is very similar to a dc generator. This is also well known that the dc machines can be used as a generator as well as as a motor, their is the difference of operation in both case i. Dec 25, 2017 in this video you will learn about speed control of dc shunt motor now you can join our whatsapp group. An efficient method for speed control of dc shunt motor using. Because of this feature, this motor is used for automotive and industrial purposes where fine precision of the motor speed is required. Construction and principle of operation of the shunt dc motor. The field current can be changed by changing the rheostat r connected in series with the field. Motor speed control laboratory equipment and software required.
Speed control of a dc motor is either done manually by the operator or by means of an automatic control device. The armature of the shunt motor m whose speed is to be controlled is connected directly to a d. Armature resistance control and field flux control the dc motor converts the mechanical power into dc electrical power. Speed control of dc shunt motor with field and armature rheostat control 79 2. C shunt motor as a function of armature voltage, field current, and external resistance in the armature circuit. The objective of the paper is to develop a simulation of speed control and protection of dc shunt motor and analyze the characteristics of the drive system under the influence of fault. Dc shunt motor shunt wound dc motor principle, construction. Therefore, speed of the motor is directly proportional to the induced emf i. 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. Speed control methods of dc shunt motor my tech info. Working principle of dc shunt motor your electrical guide. The set up for speed control of dc shunt motor using flux control technique is shown in the figure. To control the speed of dc shunt motor using field control method. Speed control of dc motor the speed of a dc motor is given by i.
Thyristor scr speed control of a dc shunt motor dspace repository thyristor scr speed control of a dc shunt motor. 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 machine used in this experiment is a representative of an industrial dc motor or generator with a rated power of tens of kilowatts. Speed control of dc shunt motor with field and armature. The amount of increase in speed depends upon the value of varible resistance r. The voltage applied to the motor may be reversed by backing the field current of generator through controller fc. C shunt motor as a function of armature voltage, field current, and external. A shuntwound motor has decreasing torque as speed increases. That method is to change the terminal voltage of the motor.
The torque developed by a dc motor is directly proportional to the armature current and the stator flux. The purpose of this experiment is to design and implement a closeloop speed control of a dcmotor drive. We shall use the same dcmotor for which the parameters were calculated in. To obtain the characteristics of speed control by the above mentioned methods. The backemf is given by lafifiaw, where if is the field current, ia is the. All the measurements were taken in such a way that constant braking force is achieved.
Tech student, department of electrical engineering mpct gwalior india 2assistant professor, department of electrical engineering mpct gwalior india. Measurements and mathematical modeling of a dc motor for. Mod01 lec32 lecture32speed control of dc shunt motors. We can control the shunt field current by inserting a rheostat. This can be achieved by changing the field current.
To study the behavior of a shunt dc motor speed when a series resistor is inserted in the armature circuit. Speed control of dc shunt motor with comparative analysis. Speed control of dc motor shunt motor and series motor. Voltage control can be via a mosfet pwm circuit, or for mains powered application, scrs. 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. A shuntwound motor has good speed regulation, and it is classified as a constant speed motor, even though the speed does decrease slightly as load is increased. 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. Speed control of dc shunt motor by varying field flux. In the case of a dc motor, the magnetic field is produced by the field winding. Title of the experiment page no 7 retardation test on dc shunt motor. And for this reason both the armature winding and the read more. 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. 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.
This double dependence makes it impossible to keep the speed sensibly constant on rapidly changing loads. The shunt wound dc motor falls under the category of self excited dc motors, where the field windings are shunted to, or are connected in parallel to the armature winding of the motor, as its name is suggestive of. Feb 05, 2018 for a dc shunt motor if the field is excited separately through a breaker than by controlling the armature voltage we can control the speed of the motor. Since they are connected in parallel, the armature and field windings are exposed to the same supply voltage.
The dc supply is switched on with minimum resistance in the field circuit and maximum value of r 1 in the armature circuit. The purpose of this experiment is to design and implement a closeloop speed control of a dc motor drive. In general, the field gets constant voltage, and the armature gets variable voltage to control the speed. When a shunt dc motor reaches its full speed, the armature current is directly related to the motor load. The present research work deals with the application of response surface methodology rsm for controlling as well as estimating the rotating speed of a dc shunt motor.
May 24, 2015 merits and demerits of rheostatic control method 1. In order to change the speed, we have to change flux. Nov 09, 2011 the amount of increase in speed depends upon the value of varible resistance r. Speed changes with every change in load, because speed variations depend not only on controlling resistance but on load current also. Such a fine speed control is generally not possible with a. In this paper, various speed control techniques for a dc shunt motor namely. To have a constant torque through all the range of motor speed, we had to change input control voltage to electric brake during the experiment. View notes speedcontrolofdcshuntmotor from boston 6. This lab allowed us to further investigate the characteristics of the various dc motor speed control schemes. Apr 16, 2017 you need to power the field and armature separately. In experiment3 and 4, the speed of the dcmotor was controlled by using an openloop voltage control. This type of control can only be used for speed control below the rated speed.
Performance of dc motors experiment the result getting is not 100% legit slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. The circuit is connected as shown in the circuit diagram. This system is used where very sensitive speed control of motor is required e. Apply a load to your dc motor by varying the dynamometer control knob until the scale marked on the dynamometer. To study the behavior of a shunt dc motor speed when a. Speedcontrolofdcshuntmotor page 1 experiment no 9 aim. Jul 10, 2012 mod01 lec32 lecture32 speed control of dc shunt motors. M1 may be any ac motor or dc motor with constant speed. Presentation on speed control and braking of dc shunt motor. Shunt wound dc motor or dc shunt motor is a selfexcited dc motor whereas we said before at previous article types of dc motor that it operates on direct current and the field winding is connected in parallel to the armature winding so both windings exposed to the same power supply voltage, and this motor able to maintain at a. 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. As resistance increased, the value of the field current will reduce. In fact, fine speed control is one of the reasons for the strong competitive position of d.
Dc shunt motor speed control and analysis using ziegler. Experiment 6 shunt dc motor ii objective to study the behavior of a shunt dc motor speed when the field resistance is altered. Tarun agarwal is the chief customer support officer at. For a dc shunt motor if the field is excited separately through a breaker than by controlling the armature voltage we can control the speed of the motor. The dc shunt motor is 120vdc with rated speed of 1800 revolutions per minute. Conclusion in this lab experiment the dc motor speed control. We shall use the same dc motor for which the parameters were calculated in the. Before the magnetic saturation, the field flux is directly proportional to the field current.
On occasion, a field regulator is contained within the field circuit of dc shunt motor for additional speed adjustment. Merits and demerits of rheostatic control method 1. Simulation of speed control and protection of dc shunt motor. In a shunt motor, the field winding, as we ll as the armature winding, is connected in. Once the motor reaches its full speed, it remains constant. One can control the speed of a dc shunt motor in two ways. 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.
Speed control of dc motor the speed of a dc motor is given by i flux control. In a shunt motor, the field and armature windings are connected in parallel. Speed control of dc shunt motor with comparative analysis with pi and fuzzy controller approach bhaskar roy1 and shilpi sisodiya2 1 m. May 25, 2015 factors controlling motor speed it has been shown earlier that the speed of a motor is given by the relation it is obvious that the speed can be controlled by varying i fluxpole, f flux control ii resistance ra of armature circuit rheostatic control and iii applied voltage v voltage con trol. By means of this method, the motor can be worked at any speed up to its maximum speed. The arrangement of this system is as shown in the figure at right. Sep 30, 2012 performance of dc motors experiment the result getting is not 100% legit slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising.
This paper describes a matlabsimulink realization of the direct current dc motor speed control method by controlling the voltage applied to the field circuit of a separately excited dc motor in. Jul 11, 2019 speed control of a dc motor is either done manually by the operator or by means of an automatic control device. As a result, the dc shunt motor is capable of maintaining a constant speed irrespective of load changes. Working principle of dc shunt motor, dc series motor and all other dc motors can be stated as follows. The physical implications of the equations regarding device behaviour, and the need for speed control, are easily understood.
Speed control of dc shunt motor your electrical guide. From the expression of the speed of a dc motor, we have seen that the speed of the motor is inversely proportional to its field flux. In experiment 3 and 4, the speed of the dc motor was controlled by using an openloop voltage control. Since load is very small in a shunt motor, armature current is also very low. When a current carrying conductor is placed in a magnetic field, it experiences a force. A stab is shaped piece of metal that makes up a certain type of wound rotor. In this post, we will discuss about various speed control methods of dc shunt motor. In this lab experiment, the dc motor speed control was studied. If you continue browsing the site, you agree to the use of cookies on this website. It would be called speed control of separately excited dc motor. The field of the shunt motor is supplied from a constantvoltage exciter e.