Speed control of separately excited dc motor and performance analysis by software simulation has been done. The core losses are 200 w, and the mechanical losses are 240 w at full load. Pdf speed control of separately excited dc motor with efficiency. Close loop control is done in two loop, first inner current loop having currenttorque controller and outer speed controller loop control the speed. Characteristic of separately excited dc generator my tech info. Speed control of separately excited dc motor by ppt 2 free download as powerpoint presentation. Speed control of dc motor using power electronic switch. Characteristic of separately excited dc generator my. Figure 2 shows the experimental setup of rectifier based separately excited dc motor it can be seen from the figure 2 that the input supply is ac.
Dc motors although ac motors are used in most of the cases, dc motors have many applications and used for multipurpose applications. The dc separately excited shunt generator instructions for students. The apparent drawback of a separately excited dc generator is that we have a tendency to need an external dc supply for excitation. Separately excited dc motor electronic components systems. In this case, the generator is referred to as shunt. I seem to be stuck on the efficiency vs torque of the motor. Power quality an alyzer is used to measure the harmonic distortion and the power factor before and after installation of filter. Jan 09, 2018 in a separately excited dc motor the supply is given separately to the field and armature windings. It shows the steady state characteristic of dc generators. Alternatively, it may be noted that the output of the dc generator is unidirectional and therefore may be used as a source to supply its own field current, as shown in figure 7b. In the separate motor, we supply the field winding from a separate dc power source. Before starting the motor, set the excitation current to its rated value check the machine name plate. Separately excited dc motor can be used for variable speed application. Learn about the different types of dc motor and their applications.
Power factor improvement of acdc converter based on. The novelty of this paper lies in the application of nonlinear autoregressivemoving averagel2 controller for the speed control of sedm. Direct current field control load torque direct current motor. Instruction worksheet 2 of 3 dc separatelyexcited motor speed and voltage characteristic n fv experiment 3. The name suggests the construction of this type of motor. Modeling block diagram of separately excited dc motor 2 2. Nikhil chowdhary akansha 1473720006 department of electrical engineering rajkiya engineering college ambedkar nagar224122u. Magnetic or open circuit characteristic of separately excited dc generatorthe curve which gives the relation between field current if and the generated voltage e0. The armature circuit for a dc machine and two circuit connections for the armature and field circuits, a shunt connected machine and a separately excited machine are presented. Write a power balance for a separately excited motor and compute its efficiency explain how changing motor load affects efficiency. Types of dc motors separately excited motor shunt excited motor series excited motor compound excited motor permanent magnet pm motor. Write a power balance for a separately excited motor and compute its efficiency. Separately excited sx transistorized traction dual motor control installation and operation manual ic3645sr3r404r2, ic3645sr3r404r3 and ic3645sr3r404r4 note.
It directly provides rotary motion and, coupled with wheels or drums and cables, can provide translational motion. Types of dc generator separately excited and self excited the dc generator converts the electrical power into electrical power. Identify and utilize equations that represent motor performance to solve separately excited dc motor problems. Mathematical modeling and close loop speed control of separately excited dc motor. Speed control of a separately excited dc motor engineering.
You must read this lab sheet prior to your lab session. The main differentiate fact in both of these types of dc motor is that the armature. After obtaining the complete model of dc drive system, the model is simulated by matlab. Modeling and speed control of separately excited dc motor. When a separately excited motor is excited by a field current of if and an armature current of ia flows in the circuit, the motor develops a back emf and a torque to balance the load torque at a particular speed. Explain how changing motor load affects efficiency. Icmieepi140153 electromechanical modeling of separately.
Im doing a lab report for a shunt dc motor evaluation. Dc motors, generators and energy conversion devices lesson 11. Eq5, eq6 and eq7 are correct for a motor with a separately excited field. The purpose is to achieve accurate trajectory control of the speed of saperately excited dc motor, especially when the motor and load parameters are unknown. Speed control of a separately excited dc motor engineering essay.
Types of electric motors electric motors dc motors other motors h ac motors s unt motor separately excited induction motor stepper motor motor brushlessdc motor series motor hysteresis motor permanent magnet dc pmdc synchronous motor reluctance motor compounded motor universal motor. Types of dc generatorseparately excited and self excited. A good material for the poles of a pmdc motor should have the apposite of the above. Apr 11, 2017 speed control of dc motor using chopper 1. The purpose is to achieve accurate trajectory control. The objective of this research work is to develop an experimental model of single phase acdc converters based separately excited dc motor to analyze the harmonics caused by nonlinear nature of power electronics acdc converters and using single tuned passive filter to reduce harmonics according to ieee standards 519 1992 and power factor. The working principle of seperately excited dc motor is listed in points below. Speed conrol of separately excited dc motor using fuzzy.
What is the relationship between speed and torque in a. The separately excited dc motor system offers many of the features that are generally found on the advanced ac systems. In a wound field machine, the flux is produced by a field winding. In a separately excited dc generator, the field winding is excited by an external independent source.
Pdf speed control of separately excited dc motor using. Shunt motor is the most common types of dc motor where we connect the field winding parallel with the armature windings so this motor can be self excited from the armature windings and this gives it the feature of greatest speed regulation, simplified reversing control and low starting torque, so shunt motor is suitable for beltdriven. A simple explanation of the different types of dc motors. The field current if excites the separately excited dc motor.
The principle of commutation is illustrated in fig. The electric circuit of the armature and the freebody diagram of the rotor are shown in the following figure. Characteristic of dc generators separately excited self excited and compound generator characteristic is the graph between the two dependent quantities. Dec 24, 2017 separately excited dc motor solution with simulink by matlab dc motor excited. In a separately excited dc motor the supply is given separately to the field and armature windings. Later parameter identification has been carried out to find the suitable design criteria for testing different controllers p, pi, pd, pid controllers with the machine.
As the name suggests, in case of a separately excited dc motor the supply is given separately to the field and armature windings. Draw a circuit model of a separately excited dc motor. View lab report lab 4 the separately excited dc generator. Historically, most electric vehicles have relied on series motor designs because of their ability to produce very high levels of torque at low speeds. Objective to study the properties of the separately e xcited dc shunt generator under no load and fullload conditions. Dc motor is still the most common choice if wide range of adjustable speed drive operation is specified. Separately excited motor examples 1 lesson 11 332a. The modeling block diagram of a separately excited dc motor is shown as fig2.
Design and development of a wind turbine simulator using a. The separately excited dc motor system offers many of the features. The objective of this paper is to describe the principle of dc motor speed control using. Also note that in the above you generated a dc motor model from the individual mechanical and electrical aspects of the motor. If external mechanical power is applied to a dc motor it acts as a dc generator, a dynamo. The separately excited dc motor can be controlled from below and up to rated speed.
Dc motor principle a machine that converts dc power into mechanical energy is known as dc motor. The circulating current in the field windings produces a magnetic flux, and the phenomenon is known as excitation. Equivalent circuit of compound excited dc motor differential compound torque t. Dc motors, generators and energy conversion devices. There are generally three most important characteristic of dc generator. Types of dc motor self excited, separately excited dc motor. Pdf speed control of separately excited dc motor and performance analysis by software simulation has been done.
Among the three types of dc motors, such as series, shunt and separately excited dc motors. For this example, we will assume that the input of the system is. Simulink separately excited dc motor matlab answers. Shunt motor is the most common types of dc motor where we connect the field winding parallel with the armature windings so this motor can be selfexcited from the armature windings and this gives it the feature of greatest speed regulation, simplified reversing control and low starting torque, so shunt motor is suitable for beltdriven. By controlling the field fluxes through variable resistance we can control the speed of the dc motor. A separately excited dc motor has field and armature windings connected to two different sources. This paper presents the speed control of a separately excited dc motor using fuzzy logic control flc. The characteristic of the dc generators explain the relations between the loads, excitation and terminals voltage through graph. The principle of working of a dc motor is that whenever a current carrying conductor is placed in a magnetic field, it experiences a mechanical force. The objective of this research work is to develop an experimental model of single phase ac dc converters based separately excited dc motor to analyze the harmonics caused by nonlinear nature of power electronics ac dc converters and using single tuned passive filter to reduce harmonics according to ieee standards 519. The most popular of the separately excited motor is.
A series dc motor has both field and armature windings connected in series. The main distinguishing fact in these types of dc motor is that, the armature current does not flow through the field windings, as the field winding is energized from a separate external source of dc current as shown in the figure beside. The rotor speed of the dc motor can be made to follow an arbitrarily selected trajectory. A common actuator in control systems is the dc motor. Oct 17, 2014 mathematical modeling and close loop speed control of separately excited dc motor.
The following is what i have to do with it after i. Characteristic of separately excited dc generator electrical4u. This paper describes speed control of separately excited dc motor using chopper as power converter and pi as speed and current controller. These are now replaced with large ac motors with variable frequency drives. Different speed can be obtained by changing the armature voltage and the field voltage. Separately excited dc motor has field coils similar to that of shunt wound dc motor. The magnetic flux in a dc machine is produced by the field coils carrying current. Pdf dc motors are exceptionally eminent in various applications where speed is the foremost aspect such as industrial applications, robot manipulators. The function of nn is to predict the field current that realizes the field weakening to drive the motor over rated speed. Is there anyone who can create it and share it in file exchange thanks in advance for the advice.
This paper proposes the speed control of a separately excited dc motor varying armature voltage. Here the speed control is similar to the speed con trol of separately excited dc. The field of them does not need any separate excitation. It is a simple, low power and low cost design that can be easily connected to an ac system through an inverter. What are the applications of a separately excited dc motor. Large dc motors with separately excited fields were generally used with winder drives for mine hoists, for high torque as well as smooth speed control using thyristor drives.
Aug 03, 2018 in a separately excited dc generator, the field winding is excited by an external independent source. A antiwindup technique is used in controller to avoid integrator windup problem. Historically, most electric vehicles have relied have on series motor designs because of their ability to produce very high levels of torque at low speeds. Field weakening control of a separately excited dc motor. In armature control, speed controller has been used in outer loop while current controller in inner loop is used. The single phase fully controlled bridge converter is obtained by replacing all the diode of the corresponding uncontrolled converter by thyristors. Jul 11, 2019 as the name suggests, in case of a separately excited dc motor the supply is given separately to the field and armature windings. Pdf control of separately excited dc motor researchgate. Optimization filter of speed is obtained using modulus hugging approach. The information contained herein is intended to assist oems, dealers and users of electric. Usually, in other dc motors, the field coil and the armature coil both are energized from a single source. Characteristic of dc generators separately excited self.
We will consider three types of wound field dc machine. The separately excited brushed dc motor lends easily to simple control, by virtue of the brush commutator which offers decoupled control via. Speed control of dc motor using chopper presented by. The separately excited dc motors are most often used. Discussion a dc machine can run either as a motor or as a generator. The main distinguishing fact in these types of dc motor is that, the armature current does not flow through the field windings, as the field windin. A separately excited dc motor is rotated at rpm and the variation of armature terminal voltage as a function of field current is measured under opencircuit conditions and tabulated below. However ever since the output voltage could also be controlled a lot of simply and over a wide range from zero to a maximum, this sort of excitation finds several applications. Types of dc motors and their applications electrical4u.
This paper also discusses speed control of a sedm using chopper circuit. In a pm dc machine, the armature circuit model is the complete circuit model. Speed control of dc motor using chopper slideshare. Get your circuit checked by the lab instructor before you switch on the power supply.
The torquespeed relationship, valid for both shunt and separate excitation, is derived. Speed control of separately excited dc motor by ppt 2. Follow 25 views last 30 days aaron connell on 4 dec 2016. This paper presents the speed control of a separately excited dc motor using neural network nn controller in field weakening region. Indeed, the rle load shown in this figure may represent the electrical equivalent circuit of a separately excited dc motor. Other articles where separatelyexcited dc generator is discussed. What are the differences between separately excited and. What is the relationship between speed and torque in a separately excited dc motor.
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