Speed control of dc shunt motor by varying field flux. The variable speed drives, which can control the speed of a. Speed control of shunt dc motor two common ways in which the speed of a shunt dc machine can be controlled. Blocks pertinent to the control of the dcmotor are modeled using.
If you are a student of electrical engineering then you should know that speed control of dc shunt motor. Thyristor scr speed control of a dc shunt motor dspace repository thyristor scr speed control of a dc shunt motor. Pdf this paper discusses the speed and torque control of a shunt dc motor through matlab simulink simulations. In this lesson aspects of starting and speed control of d. C shunt motor as a function of armature voltage, field current, and external resistance in the armature circuit. Therefore the voltage drops i a r a will be negligible as compared to the external supply voltage v. 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. In fact, fine speed control is one of the reasons for the strong competitive position of d. Blocks pertinent to the control of the dc motor are modeled using basic blocks.
The less common method of speed control is by inserting a resistor in series with armature circuit. In the flux control method for controlling the speed of d. Dc motor speed control is carried out by use of four quadrant chopper drive. Ra when the armature current is increased the speed value can be decreased. By decreasing the flux, the speed can be increased and vice versa. Field control method on separately excited dc motor. The dc shunt motor is 120vdc with rated speed of 1800 revolutions per minute. Because of their selfregulating speed capabilities, dc shunt motors are ideal for applications where precise speed control is required. Speed control of dc shunt motor your electrical guide. Until the late of the 1980s, when the variable frequency drive was not invented, dc motor was the best option for variable speed application. The different methods of speed control of dc shunt motor are flux control method, armature control method and voltage control method.
The voltage applied to the motor may be reversed by backing the field current of generator through controller fc. It is a machine which converts electrical energy into mechanical energy. Speed control of dc motor the speed of a dc motor is given by i flux control. To study the methods of controlling the speed of separately excited dc motor. Wordpress link to get the summary of the lecture in pdf. In this method, speed variation is accomplished by means of a variable resistance inserted in series with the shunt field. By this method a dc shunt motor s speed is controlled through a field rheostat. We use this method to increase the speed of these motors above the base speed. In a shunt motor, the field and armature windings are connected in parallel. What is the difference between a dc shunt and a series motor. Todays industries are increasingly demanding process automation in all sectors. Before the magnetic saturation, the field flux is directly proportional to the field current.
What is a dc shunt motor definition, characteristics. He has 8 years of experience in customer support, operations and administration. Speed control of dc shunt motor using microcontroller. A dc shunt motor also known as a shunt wound dc motor is a type of self excited dc motor where the field windings are shunted to or are. Speed control of dc motor shunt, series and compound. This item appears in the following collections higher diploma in electrical and electronics engineering 22 projects. Introduction to dc motors 1 ee 448 lab experiment no. The speed of a shunt motor can be changed by flux control method. A very important and interesting fact about the dc shunt motor, is in its ability to selfregulate its speed on the application of the load to the shaft of the rotor terminals. To study the methods of controlling the speed of shunt dc motor. Keep in mind, however, that they cannot produce high starting torque, so the load at startup must be small.
This paper describes a matlabsimulink realization of the. 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. By adjusting the duty cycle of pulse from pulse width modulation technique simultaneously. Speed control of dc motors field control shunt motor.
Speed of a dc motor we know, back emf of a dc motor eb is the induced emf due to rotation of the armature in magnetic field. Speed of a dc motor can be controlled by various ways, like flux control. Speed control methods of dc shunt motor my tech info. In a shunt motor, the field winding, as we ll as the armature winding, is connected in.
P3 odd semester examination 2019 department of eee. Indeed one of the primary reasons for the strong competitive position of dc motors in modern industrial drives is the wide range of speeds afforded. Such a fine speed control is generally not possible with a. The field winding is connected in parallel with the armature. In this session we will discuss the armature voltage control technique of the speed control of dc shunt motors. Data sheet d210 kbic variable speed dc motor controls for shunt wound, pm and ac dc motors 1100 11. The problem with this method is that when we increase the resistance, the slope becomes steeper. Before discussing the speed control of dc shunt motor, we have to find the factors affecting the speed of a dc motor. Of course, before going to know speed control of dc shunt motor we will learn what is dc shunt motor. Speed control methods of dc motor speed control of shunt motor 1. The electrical machine is one of the most important subject in electrical engineering. Automation results into better quality, increased production an reduced costs. This paper discusses the speed and torquecontrol of a shunt dc motor through matlab simulink simulations.
It will run equally well using either an ac or a dc voltage source. Set the shunt field rheostat control knob at its full cw position for. We control the speed by adding a variable resistance in series with the shunt field, when we increase the resistance the field current reduces and by the way, the flux reduces and the speed increases. Speed control of dc shunt motor with field and armature rheostat control 79 2. Therefore speed of the 3 types of dc motors shunt, series and compound can be controlled by changing the quantities on the righthand. In shunt dc motors the variable resistance inserted as, field control method on shunt dc motor. Dc motor generator module to demonstrate and explain the operation of. Speed control of shunt dc motor johurul islam academia. An increase in controlling resistances reduces the field current with a reduction in flux and an. 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. 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. Content speed of a dc motor speed control methods of dc motor speed control of shunt motor speed control of series motor 3. Equivalent circuit parameters are armature resistance ra 110 ohms, field resistance rf 2.
The speed control of this type of motor is achieved by varying either the armature current or armature resistance or by varying the terminal voltage applied the speed relation of dc shunt type motor is given as n. This paper discusses the speed and torque control of a shunt dc motor through matlab simulink simulations. We can control the shunt field current by inserting a rheostat. As a dc shunt motor attains its complete speed, then the armature current can be directly connected to the motor load.
Armature resistance control and field flux control the dc motor converts the mechanical power into dc electrical power. By means of this method, the motor can be worked at any speed up to its maximum speed. Speed control of dc shunt motor with field and armature rheostat. The backemf is given by lafifiaw, where if is the field current, ia is the. Speed control of dc shunt motor with field and armature. Speed control methods of dc shunt as well as dc series motor are. 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. Adjusting the field resistance r f and thus the field flux adjusting the terminal voltage applied to the armature. 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.
The speed control of dc motors are in general much more adaptable speed drives than ac motors which are associated with a constant speed rotating field. As resistance increased, the value of the field current will reduce. On occasion, a field regulator is contained within the field circuit of dc shunt motor for additional speed adjustment. Motors plays an important role in energy conversion process. Pdf speed control of dc motor by using pwm technique. The flux of a dc motor can be changed by changing ish with help of a shunt field. This essentially means that on switching the motor running condition from no load to loaded, surprisingly there is no considerable change in speed of running, as would. Tarun agarwal is the chief customer support officer at edgefx technologies pvt ltd. We know that the expression of speed control dc motor is given as. The speed characteristic of a shunt motor is different compared with a series motor. Dc shunt motor speed control and analysis using ziegler. When the load is extremely low within a shunt motor, then the armature current can also be low.
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