File Name: dc and ac machines short notes .zip
A DC motor is any of a class of rotary electrical motors that converts direct current electrical energy into mechanical energy.
A device that transforms the form of input electrical energy to an output mechanical energy. Basically, there are two types of electrical motors they are the DC and AC type. The DC type machines are normally used in small applications whereas the AC type has its importance in a wide range of applications. Because the AC machines have more advantages compared to that of DC machines. In this article, we shall discuss what is AC motor, construction, working principle, types, speed control, and applications.
Definition : Electric motor is the electro-mechanical machine which converts the electrical energy into mechanical energy. In other words, the devices which produce rotational force is known as the motor. The working principle of the electric motor mainly depends on the interaction of magnetic and electric field. The electric motor is mainly classified into two types. They are the AC motor and the DC motor.
In electrical engineering , an armature is the component of an electric machine which carries alternating current. The armature can be on either the rotor rotating part or the stator stationary part , depending on the type of electric machine. The armature windings interact with the magnetic field magnetic flux in the air-gap; the magnetic field is generated either by permanent magnets, or electromagnets formed by a conducting coil. The armature must carry current , so it is always a conductor or a conductive coil, oriented normal to both the field and to the direction of motion, torque rotating machine , or force linear machine. The armature's role is twofold. The first is to carry current across the field, thus creating shaft torque in a rotating machine or force in a linear machine. The second role is to generate an electromotive force EMF.
We think you have liked this presentation. If you wish to download it, please recommend it to your friends in any social system. Share buttons are a little bit lower. Thank you! Published by Ariel McGee Modified over 2 years ago. Discuss the operating differences between different types of generators Understand the principle of DC generator as it represents a logical behavior of dc motors. Most DC machines are similar to AC machines: i.
A DC Machine is an electro-mechanical energy conversion device. The AC motor is invariably applied in the industry for conversion of electrical power into mechanical power, but at the places where the wide range of speeds and good speed regulation is required, like in electric traction system, a DC motor is used. The construction of the dc motor and generator is nearly the same. The generator is employed in a very protected way. Hence there is an open construction type. But the motor is used in the location where they are exposed to dust and moisture, and hence it requires enclosures for example dirt proof, fireproof, etc. Although the battery is an important source of DC electric power, it can only supply limited power to any machines.
The magnetic flux in a d. The production of magnetic flux in the device by circulating current in the field winding is called excitation. There are two types of excitation in D. C machine. Separate excitation, and self-excitation.
In actual practice, both of the primary and secondary windings have got some ohmic resistance causing voltage drops and copper losses in the windings. In actual practice, the total flux created does not link both of the primary and secondary windings but is divided into three components namely the main or mutual flux f linking both of the primary and secondary windings, primary leakage flux fL 1 linking with primary winding only and secondary leakage flux fL 2 linking with secondary winding only. The primary leakage flux fL 1 is produced by primary ampere-turns and is Proportional to primary current, number of primary turns being fixed. The self induced emf divided by the primary current gives the reactance of primary and is denoted by X 1.
LECTURE NOTES. ON this module we will be discussing the three phase induction machine. motor means there is requirement of separate dc excitation.
The conversion of this mechanism is known as the commutator, thus these machines are also named as commutating machines. DC machine is most frequently used for a motor. The main benefits of this machine include torque regulation as well as easy speed. The applications of the DC machine is limited to trains, mills, and mines. For example, underground subway cars, as well as trolleys, may utilize DC motors. In the past, automobiles were designed with DC dynamos for charging their batteries.
Не может быть, что служба уже закончилась. Это невозможно. Да мы только вошли. Но, увидев прислужника в конце ряда и два людских потока, движущихся по центральному проходу к алтарю, Беккер понял, что происходит. Причастие.
Она мне нужна. Сьюзан даже вздрогнула от неожиданности. - Вам нужен ключ. Я поняла так, что весь смысл в том, чтобы его уничтожить. - Верно. Но я хочу иметь копию.
- Ты считаешь, что мы готовы взять на себя такую ответственность. Ты считаешь, что кто-нибудь готов. Это же крайне недальновидно. Ты говоришь, что наше дерьмовое правительство исходит из высших интересов людей.
Стратмор покачал головой: - Танкадо дал нам шанс. Это совершенно ясно. Тем не менее риск велик: если нас обнаружат, это, в сущности, будет означать, что он своим алгоритмом нас напугал. Нам придется публично признать не только то, что мы имеем ТРАНСТЕКСТ, но и то, что Цифровая крепость неприступна. - Каким временем мы располагаем.
Вы хотите отправить его домой. - Нет. Пусть остается.
are called field windings. ❑ The rotor contains the commutator and the conductors across which emf is induced. This part is called armature. DC Machines.Reina M. 13.05.2021 at 02:10
power factor compensators (synchronous condensers). ii) Asynchronous (Induction) Machines: • Induction Motors: Most widely used electrical motors in.Christophe G. 15.05.2021 at 12:32
From an electrical point of view, any conventional DC or AC machine consists of EE laboratory manual and lecture notes, Middle East Technical University.Robert B. 16.05.2021 at 08:34
1 | Page. DC MACHINES AND TRANSFORMERS. LECTURE NOTES. Dr. P Sridhar. Professor & Head. Department of Electrical and Electronics Engineering.