This field tries to drag the rotor with it, but could not do so because of rotor. There are many types of ac motors, but this course focuses on threephase induction motors, the most common type of motor used in industrial applications. When supply is given to synchronous motor, a revolving field is set up. Ac series motor principle, types, characteristics and. An induction motor can be defined as the ac electric motor device in which a power source fed by the alternating current with the help of a primary winding. In the case of three phase ac alternating current operation, the most widely used motor is a 3 phase induction motor, as this type of motor does not require an additional starting device. The schematic diagram of servo system for ac twophase induction motor is shown in the figure below. An ac motor is an energy conversion device that converts input electrical energy into power for rotation and outputs it. This course consists of 11 interactive, online lessons that address ac and dc motor theory. The threephase induction motor is the extensively used for various kinds of industrial drives.
Of course, the working principle of the ac motor doesnt differ a lot than the dc motor, but its able to run on both ac and dc current. Virtually all electrical motors use magnetic field rotation to spin their rotors. The rotor will constantly be turning to align its magnetic field with that of the stator field. Generator working principle and explain about ac and dc. Direct vs alternating current distribution systemsthat are far more ef. The operation principle of ac motors can be explained by using aragos disk. Unit 16 electric motors objectives after studying this unit, the student will be able to. An ac motor of this type may be part of a pump or fan or connected to some other form of mechanical equipment such as a winder, conveyor, or mixer. Apr 14, 2020 dc motor explained in this video we look at how does a dc motor work to understand the basic working principle of a dc motor. This portable document format \ pdf \ file contains bookmarks, thumbnails, and hyperlinks to help you navigate through the document.
Electrical energy is not 100% converted to power, and some energy is lost heat. An induction motor also known as an asynchronous motor is a commonly used ac electric motor. What is common to all the members of this family is that the basic physical process involved in their operation is the conversion of electromagnetic energy. The theory used in the work was collected by studying literature on how electrical motors work, and by simplifying the. Describe the differences between the two basic types of ac generators. Generally, it is known as the asynchronous motor because its running speed is less than its synchronous speed. Less common, ac linear motors operate on similar principles as rotating motors but have their stationary and. The working principle of this servo motor is similar to the normal induction motor. What is common to all the members of this family is that the basic physical process involved in their operation is the conversion of electromagnetic energy to mechanical energy, and vice versa.
Oct 28, 2015 the working principle of this servo motor is similar to the normal induction motor. To some, motor speed control is somewhat of a mystical science, a science that causes motors and machines to sometimes operate in unexpected ways. Advantages of 3 phase induction motor generally easy to build and cheaper than corresponding dc or synchronous motors induction motor is robust. Dc motors although ac motors are used in most of the cases, dc motors have many applications and used for multipurpose applications. An electrical motor is a device that has brought about one of the biggest advancements in the fields of engineering and technology ever since the invention. Using four rotors made out of four di erent materials would allow us to get very complete data. It is just made up of simple motor which run through servo mechanism. The field windings of a series motors are connected in series with the armature windings. A servo motor is an electrical device which can push or rotate an object with great precision. We have a wound armature and field that are interconnected in series. Basic principle the electric motor operation is based on the following points.
A kind of induction motor and a motor having the same characteristic in any direction such as left turn or right turn. The operating principle of the induction motor can be briefly explained as. Describe how a squirrel cage motor is built, and classify it as either an induction motor or a synchronous motor. A wound rotor, has a 3phase winding similar to the stator winding. Explain how this motor can be operated as either a synchronous motor or a plain induction motor. The first invertersconverters used motorgenerator sets, but were costly, heavy and inefficient. These generators are generally maintenance free, because of absence of brushes. These generators are packaged with an engine or turbine to be used as a motorgenerator set and used in applications like naval, oil and gas extraction, mining machinery, wind power plants etc.
If a company wanted to have reliable production, it should stick with known, proven. To understand the operating principle of dc motor we need to. An ac motor is an electric motor driven by an alternating current ac. Over 30 years ago, ac drives were considered new technology. In general, the induction motor is cheaper and easier to maintain compared to other alternatives. It is a maintenance free, less noisy and efficient. Module 7 basic ac theory this module describes the basic concepts of alternating current ac electrical circuits and discusses the associated terminology.
Alternating current generators learning objectives upon completion of this chapter, you will be able to. Dc motor explained basic working principle how dc motor. Thermal cutouts or motor overload devices are not branchcircuit protection. To explain the details of why this is so, a bit of background knowledge about ac is necessary.
The induction motor is made up of the stator, or stationary windings, and the rotor. Ac motors ac motors are used worldwide in many applications to transform electrical energy into mechanical energy. This type of motor operates like a twophase ac motor and is used to drive actuators. Induction motor theory jerry bednarczyk, pe course content introduction the ac induction motor is well suited to applications requiring constant speed operation. The rst major design decision was to build a motor that would facilitate our experiment as e ectively as possible. Working principle of dc motor dc motor, dc generator both descended from the same family dc machine which means that there isnt a big difference between dc motor and dc generator contrary we will find lots of similarities between them so lets go. In this chapter, we shall focus our attention on the construction, working and characteristics of commonly used singlephase motors. Jul 11, 2019 the dc motor is of vital importance for the industry today and is equally important for engineers to look into the working principle of dc motor in details that we have discussed in this article. We consider conventional current, electron flow, the winding. The three phase induction motors are simple in construction. Principles of operation of synchronous machines the synchronous electrical generator also called alternator belongs to the family of electric rotating machines. The ac induction motor is the most used electrical motor in industrial applications worldwide. Operating principle like most motors, an ac induction motor has a fixed outer portion, called the stator and a rotor that spins inside with a carefully engineered air gap between the two. A universal motor is a singlephase series motor, which is able to run on either alternating current ac or direct current dc and the characteristics are similar for both ac and dc.
Dc motor principle a machine that converts dc power into mechanical energy is known as dc motor. Freeacceleration characteristics, a rotor speed, b torque, c phase a. The 3phase set of currents, each of equal magnitude and with a phase. Describe the principle of magnetic induction as it applies to ac generators.
Michael faraday was the first person to create a device that used an electromagnet with a permanent magnets to apply or create a. The split facing technique of ac motors is given in this video. Most electric motors operate through the interaction between the motors magnetic field and electric current in a wire winding to generate force in the form of torque applied on the motors shaft. These types of motors are known as selfstarting induction motors. Objective identify the components of an ac motor and explain their function. Its operation is based on the principle that when a current carrying conductor is placed in a. Acdc motors installation, principle of operation, troubleshooting and repair. The dc motor is of vital importance for the industry today and is equally important for engineers to look into the working principle of dc motor in details that we have discussed in this article. Induction motor seminar ppt, pdf report study mafia. An introduction to electric motors stmicroelectronics.
Modern inverters use solidstate designs and microprocessor controls to produce high quality ac power very. The induction machine is used in wide variety of applications as a means of converting. But the rotor construction differs with respect to the type of motor. To understand the operating principle of dc motor we need to first look into its single loop constructional feature. If you want to rotate and object at some specific angles or distance, then you use servo motor. The principle of an ac motor is that electric current is applied to electromagnets, creating a rotating magnetic field to convert electrical energy to rotation mechanical energy. Principle of operation of single phase induction motor. Temperature rise and heat resistant class of ac motor electrical energy conversion and loss. The most popular type is the 3phase, squirrelcage ac induction motor. A motorbranch circuit is a wiring system extending beyond the final automatic overload protective device. The maximum torque is limited by the current rating of the motor and it is obtained at zero speed startup.
List the advantages and disadvantages of the two types of ac generators. Principle of ac servo motor 3 design of motor 2 stator stator is composed of the core and winding which generates torque. Alternating current motors or ac motors are built on the principle that nikola tesla discovered in the late 19th century. Again the controller must know the exact position of the rotor using encoder for precise speed and position control.
Free download induction motor seminar ppt, pdf report. Working principle of dc motor how a dc motor works. If motor is used is dc powered then it is called dc servo motor, and if it is ac. The motor is controlled by applying a voltage to the motor leads. Module 8 ac reactive components this module describes inductance and capacitance and their effects on ac circuits. The rotor terminals are connected to three slip rings which turn with the. In this chapter, we shall focus our attention on the construction, working and. Mehta, rohit mehta for over 15 years principles of electrical machines is an ideal text for students who look to gain a current and clear understanding of the. Other motors that are included are 1phase induction motors, permanent synchronous motors and synchronous reluctance motors. Other members of the family are the directcurrent dc motor or generator, the induction motor or generator, and a number of derivatives of all these three. Motors convert electromagnetic energy into energy of motion or kinetic energy. An air conditioner collects hot air from a given space, processes it within itself with the help of a refrigerant and a bunch of coils and then releases cool air into the same space where the hot air had originally been collected.
A threephase ac induction motor is the only type where the rotating. Nov 20, 2016 the working principle of ac motors is given here. The motor that converts the ac electrical power into mechanical power and is operated only at the synchronous speed is known as a synchronous motor. Dc motors, ac theory, ac power, ac generators, voltage regulators, ac motors, transformers, test instruments, electrical distribution. The short film ac motors 1969 is available for free download at the internet archive. The direction is changed by reversing the polarity on the leads. An ac motor of this type may be part of a pump or fan or. Nov 27, 2019 an electrical motor is an electromechanical device which converts electrical energy into mechanical energy.
Dc motor explained in this video we look at how does a dc motor work to understand the basic working principle of a dc motor. The basic idea of an electric motor is to generate two magnetic fields. Ac induction motors are also the most common motors used in main powered home appliances. Working or operating principle of dc motor electrical4u.
At least one of the two magnetic field is generated by a solenoid carrying a current. Slip ring induction motor is made up from wound rotor and squirrel cage induction motor is made up from the squirrel cage rotor. Principle of ac servo motor 3 design of motor2 stator stator is composed of the core and winding which generates torque. Inverters are used in pv systems to convert direct current dc power from batteries or pv arrays into alternating current ac power. An induction motor im is a type of asynchronous ac motor where power is supplied to. Working principle of servo motor a servo motor is basically a dc motor in some spec ial cases it is ac motor along with some other special purpose components that make a dc motor a servo. Motor speed relationship the synchronous speed of an ac motor is the speed of the rotating magnetic field set up by the stator winding synchronous speed rpm 120 x frequency divided by the number of poles. The ac motor commonly consists of two basic parts, an outside stator having coils supplied with alternating current to produce a rotating magnetic field, and an inside rotor attached to the output shaft producing a second rotating magnetic field.