It would be called speed control of separately excited dc motor. Experiment 5 dc motor speed control walter scott, jr. To study the speed control of dc shunt motor by varying. Your reports should follow the prescribed format, to give your report. The spring balance should kept at zero position throughout the experiment. As resistance increased, the value of the field current will reduce. 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.
Working principle of dc shunt motor, dc series motor and all other dc motors can be stated as follows. The range of speed control and robust working adds to the usefulness of the dc motors. Therefore the voltage drops i a r a will be negligible as compared to the external supply voltage v. Below in summary charts torque to duty cycle are presented in the cases scenarios. Speed of dc motor can be varied by following methods armature voltage control for below base speed field flux control for above base speed armature resistance control here, we are using armature voltage control method for speed control.
I discuss the field resistance methos of speed control of dc shunt machinesthis lecture is a bit longbut it is worth it i have also put a summary of the lecture in pdf at this link here. There are two types of controls which were made in order to control the speed as well as the current. Electrical machinel dc laboratory manual grietelectrical and. Before discussing the speed control of dc shunt motor, we have to find the factors affecting the speed of a dc motor.
Speed control of dc shunt motor electric motor direct current. In an open loop control, the only components in the system. Automatic speed controller of a dc motor using arduino. 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 flux of a dc motor can be changed by changing ish with help of a shunt field.
The performance of speed regulation of ac motor can compare with that of dc motor after the foc. 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. Voltage control can be via a mosfet pwm circuit, or for mains powered application, scrs. C shunt motor as a function of armature voltage, field current, and external resistance in the armature circuit. Speed control methods of dc shunt motor my tech info. 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. Speed control of a dc motor is either done manually by the operator or by means of an automatic control device. To study the speed control of the given dc shunt motor by field control method and. To control the speed of dc shunt motor using armature control method. The flux is dependent on the current through the shunt field winding.
Speed control of dc shunt motor x4e60d9pz9n3 idocpub. As dc power can be easily transported, dc motor contributes a lot to traction drives. Motor speed control laboratory equipment and software required. 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 motor speed control of shunt motor 1. Speed control of dc shunt motor free download as pdf file.
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. Speed control of dc motor using chopper slideshare. The machine used in this experiment is a representative of an industrial dc motor or generator with a rated power of tens of kilowatts. 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. To observe the zero initial condition response, set these values to zero. Various induction motor speed control methods advantages. You need to power the field and armature separately. Speedcontrolofdcshuntmotor page 1 experiment no 9 aim. B simulink block of pid control dc motor experiment 77. Speed control of dc motor using pid controller based on matlab. This method is similar to armature rheostat control method of dc shunt motors. By decreasing the flux, the speed can be increased and vice versa. Thus flux can be controlled by adding a rheostat variable resistance in series with the shunt field winding, as shown in the fig.
Assuming stator flux to be linear function of field current, determine the constant kk f. 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. Armature voltage control is used to control the motor speed below the rated speed. Since they are connected in parallel, the armature and field windings are exposed to the same supply voltage. Because of its constant running speed, the synchronous motorgenerator will be used to. 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. In fact, fine speed control is one of the reasons for the strong competitive position of d. Pdf this paper discusses the speed and torque control of a shunt dc motor through matlab simulink simulations. 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. Calculate a the speed when the load current is 50a. In this experiment the mechanical characteristics b and j will be determined. As a result, the optimize of the control can be realized very difficultly in the speed control. When a current carrying conductor is placed in a magnetic field, it experiences a force.
To study the methods of controlling the speed of separately excited dc motor. In this method, a variable resistance known as shunt field rheostat is placed in series with shunt field winding as shown in fig. 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. To study the speed control of a dc shunt motor by the following methods. Tieit bhopal, mp udit narayan student of be, tieit, bhopal, mp akash verma student of be, tieit, bhopal, mp abstract. Towards to establish speed control, many tested have been taken place. And the armature winding is connected to external supply voltage hence it plays the role of current carrying conductor. With the contribution of converter the efficiency and speed control ranges is enhanced to great. This lab allowed us to further investigate the characteristics of the various dc motor speed control schemes. In this section of dc motor projects, i will provide you the list of the tutorials in which i have already controlled the speed of the dc motor using. In the case of a dc motor, the magnetic field is produced by the field winding. Dc shunt motor speed control and analysis using ziegler. The dc shunt motor is 120vdc with rated speed of 1800 revolutions per minute.
The supply is switched off after experiment is over. Such a fine speed control is generally not possible with a. Dc motors consist of one set of coils, called armature winding, inside another set of coils or a set of permanent magnets. Electrical machines for mechatronics laboratory 6 5 if a ra. From this formula it follows that the speed of a shunt d. Where,va is the voltage applied across the armature, n is the rotor speed and. Speed control of dc shunt motor armature, field control. Speed control of dc shunt motor with field and armature rheostat control 79 2. In a shunt motor, the field winding, as we ll as the armature winding, is connected in. Speed control of dc motor using pid controller based on matlab aditya pratap singh asst prof, ex dept.
Conclusion in this lab experiment the dc motor speed. Though there are separate branches for the flow of armature current and field current. He has 8 years of experience in customer support, operations and administration. Speed control of dc shunt motor with field and armature. Using pi controllers to smoothen the voltage applied to the motor. Data for speed control of a shunt dc motor using alternating armature resistance. Speed control of dc shunt motor and 3ph induction motor. 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. Download dc motor direction control proteus simulation. In this post, we will discuss about various speed control methods of dc shunt motor. This technical document is a series of laboratory manuals of electronics and. By means of this method, the motor can be worked at any speed up to its maximum speed. These methods as applied to shunt, compound and series motors will be discussed below. In this lab experiment, the dc motor speed control was studied. Keep in mind, however, that they cannot produce high starting torque, so the load at startup must be small. Instead of applying the resistance into the rotor circuit of the motor, the speed can be varied by applying emfs into the circuit. As indicated by the speed equation, the speed is inversely proportional to the flux. On occasion, a field regulator is contained within the field circuit of dc shunt motor for additional speed adjustment. In general, the field gets constant voltage, and the armature gets variable voltage to control the speed.
Because of their selfregulating speed capabilities, dc shunt motors are ideal for applications where precise speed control is required. That method is to change the terminal voltage of the motor. 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. These emfs are applied at the rotor by a suitable source whose frequency should be same as slip frequency. The purpose of this experiment is to obtain the load characteristics of dc motors. View notes speedcontrolofdcshuntmotor from boston 6. Working principle of dc shunt motor your electrical guide. The different methods of speed control of dc shunt motor are flux control method, armature control method and voltage control method. Set the shunt field rheostat control knob at its full cw position for. Speed control of dc shunt motor your electrical guide. Homework statement a 250v shunt dc motor runs at rpm while taking a current of 25 a.
Introduction to dc motors 1 ee 448 lab experiment no. This paper discusses the speed and torque control of a shunt dc motor through matlab simulink simulations. This is the basic theory by which all dc motors operate. 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. Dc motor control tutorials home the engineering projects.
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