V and 1 nd or i f 1 nd where n is the speed, v is applied voltage, ia is the armature current, and ra is the armature resistance and. 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. Dc power input is converted into mechanical power at the shaft motor. Keep in mind, however, that they cannot produce high starting torque, so the load at startup must be small. Armature resistance control and field flux control the dc motor converts the mechanical power into dc electrical power. Dc generator external characteristics of shunt generator 2 theory 2. Swinburnes test and speed control of dc shunt motor. This is the field shunt winding of the dc generator motor. Assuming stator flux to be linear function of field current, determine the constant kk f. The working principle of a dc shunt motor is, whenever a dc motor is turned on, then dc. 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. 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. Dc motor generator module to demonstrate and explain the operation of dc motors and generators operating principle of dc motors as stated in unit 1, motors turn because of the interaction between two magnetic fields. When the losses of dc machine wellknown, then we can find the efficiency of a dc machine in advance at any desired load.
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. 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. Therefore the voltage drops i a r a will be negligible as compared to the external supply voltage v. What is a dc shunt motor and its advantage and disadvantage. Speed control of dc shunt motor and 3ph induction motor. Since they are connected in parallel, the armature. To study the behavior of a shunt dc motor speed when the armature voltage is altered. In this experiment we aim to conduct a noload test on a dc generator to determine its open circuit characteristics followed by a load test on a dc shunt generator to determine its external load characteristics. Load characteristics of dc shunt and compound motor. In this experiment dc motor is being used as a prime mover. 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. To study the behavior of a shunt dc motor speed when a. These experiments consolidates the students knowledge of construction,operation and performance of dc. To conduct load test on dc shunt generator and to draw its external and.
Components of the shunt motor are the armature, labeled a1 and a 2, and the field, labeled f1 and f2. The dc shunt motor construction is the same as any type of dc motor. A dc generator is used to provide a dynamic, variable load on the shaft of the dc motor in the dynamometer cradle. The shunt motor runs at a speed defined by the expressions. Dc motor is an electromagnetic device which converts electrical energy into mechanical energy. Electrical machines lab report 12 eet2166 mmu studocu. To study the speed control of dc shunt motor by varying. Dc series motor powered by photovoltaic and dc shunt generators m. Its operation is based on the principle that when a current carrying conductor is placed in a. This article describes the construction of dc motor. To examine the behavior of dc shunt and compound motors under load. In dc machines this test is applicable only throughout the flux is constant at all load dc shunt machine and dc compound machine. The large rheostat on the panel next to the shunt circuit display is hard wired in to the shunt circuitry in series with the field shunt coil.
The coils in the shunt field are composed of many turns of small wire, resulting in low shunt field current and moderate armature current. Retardation or running down test this method is applicable to shunt motors and generators and is used for finding stray losses. Harb abstract this paper presents the dynamical model, simulation and performance characteristics dynamic and steadystate of a hybrid powered dc series motor. Characteristics of dc shunt motor, dc series motor, dc compound motor. High voltages are present in this laboratory experiment. The sources are dc shunt generator in parallel with pv generator. Then, knowing the armature and shunt cu losses at a given load current, efficiency can be calculated. Therefore speed of the 3 types of dc motors shunt, series and compound can be controlled by changing the quantities on the righthand.
Characteristics of dc shunt motor, dc series motor, dc. Modeling, simulation and performance characteristics of dc. Connect the shunt field of the dc motor generator, terminals 5 and 6, to the variable dc output of. Open circuit characteristic occ of dc shunt generator 2.
Dc motors although ac motors are used in most of the cases, dc motors have many applications and used for multipurpose applications. Experiment 5 dc motor speed control walter scott, jr. Pdf this paper discusses the speed and torque control of a shunt dc motor through matlab simulink simulations. To conduct a load test on dc shunt motor and to find its efficiency. That method is to change the terminal voltage of the motor. Open circuit characteristics of a dc generator aim 1 theory. This motor can be constructed with the basic parts like field windings stator, a commutator and an armature rotor. 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. Electric machines convert electrical energy to mechanical energy and viceversa, as shown in fig.
In dc series motors, the swinburnes test cannot be done to find its efficiency as it is a no load test. Speed control of dc shunt motor your electrical guide. Before discussing the speed control of dc shunt motor, we have to find the factors affecting the speed of a dc motor. A7 5% to 7% of rated current on primary side and full rated current on secondary side. This unit will discuss how these magnetic fields are produced in dc motors. Load test on singlephase transformer and three phase transformer connections. The machine under test is speeded up slightly beyond its normal speed and then supply is cut. Electrical4u is dedicated to the teaching and sharing of all things related to electrical and electronics engineering.
To observe the zero initial condition response, set these values to zero. Dc shunt motor free download as powerpoint presentation. Speed control of dc shunt motor with field and armature. 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 this technique, the dc generator or dc motor is run as a motor at no load. Applications that meet these criteria and are suitable for dc shunt motors include machines tool such. To study the methods of controlling the speed of separately excited dc motor. Introduction to electrical power and machines eet2166. Experiment 6 shunt dc motor ii objective to study the behavior of a shunt dc motor speed when the field resistance is altered. Dc motor principle a machine that converts dc power into mechanical energy is known as dc motor. Brake test in one of the most simple way of finding efficiency of any kind of dc machine. This paper describes a matlabsimulink realization of the. Shunt dc motor the shunt motor is probably the most common dc motor used in industry today.
Speed control of dc shunt motor with field and armature rheostat control 79 2. There is no difference in the construction of dc motor and generator. Lab report of electrical machines for lab1 characteristics of dc shunt motor, lab 1. Note that the curve bends over as the field current increases. This is the complete theory of brake test on dc shunt motor including laboratory manual. In this experiment, we will examine some key characteristics of a dc motor. Because of their selfregulating speed capabilities, dc shunt motors are ideal for applications where precise speed control is required. Characteristics of dc shunt motor, dc series motor, dc compound motor the importance characteristic of dc motor is as follows.