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The salientpole construction shown in Fig. is best adapted to multipolar, slowspeed, hydroelectric generators and to most syn chronous motors. The dc power required for excitationapproximately one to a few percent of the rating of the synchronous machinemis supplied by the excitation system. In older machines, the excitation current was typically supplied through slip rings from a dc ...
Construction of Generator The generators and motors have the same general construction. In fact, when the machine is being assembled, the workmen usually do not know whether it is a generator or motor. Any generator can be run as a motor and viceversa. All machines have five principal components viz., (i) field system (ii) armature core (iii) armature ...
Hence, let''s call this point as construction of a DC machine instead of just ''construction of a dc generator''. The above figure shows constructional details of a simple 4pole DC machine. A DC machine consists of two basic parts; stator and rotor. Basic constructional parts of a DC machine are described below. Yoke: The outer frame of a dc machine is called as yoke. It is made up of cast iron ...
• In a dc machine, the armature winding is found on the rotating member, referred to as the rotor. Elementary DC Machines • The armature winding of a dc generator is on the rotor with current conducted from it by means of carbon brushes. • The field winding is on the stator and is excited by direct current. Electric Machines General • When a machine is converting electrical energy into ...
Construction of dc Machines: The rotor in a dc machine is called an armature. The armature has cylindrical steel core that is composed of a stack of slotted laminations. Slots in laminations are aligned axially along rotor or shaft. Armature windings are placed in slots. The stator in a dc machine is the field part of the machine. Field poles are located on stator and project inward. Each pole ...
(DC) theory, circuits, motors, and generators; AC power and reactive components; batteries; AC and DC voltage regulators; transformers; and electrical test instruments and measuring devices. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility electrical equipment. Key Words: Training Material, Magnetism, DC ...
· In DC machine, mechanical energy is converted into the electrical energy. During this process, the total input power is not transformed into output power. Some part of input power gets wasted in various forms. The form of this loss may vary from one machine to another. These losses give in the rise in temperature of the machine and reduce the efficiency of the machine. In
The dc generators and dc motors have the same general construction. In fact, when the machine is being assembled, the workmen usually do not know whether it is a dc generator or motor. Any dc generator can be run as a dc motor and viceversa. Read: Working of DC Motor
Construction, Working Applications of BLDC (Brushless DC Motor) Brushless DC motors (BLDC) have been a much focused area for numerous motor manufacturers as these motors are increasingly the preferred choice in many applications, especially in the field of motor control technology. BLDC motors are superior to brushed DC motors in many ways, such as ability to operate at high speeds, high ...
• DC machines can develop rated torque at all speeds from standstill (lockedrotor) to rated speed. DC machines are easier to analyze than their AC counterparts, although their construction is made rather complex by the fact that they need a commutator, which reverses the direction of currents and fluxes to produce a net torque. • DC motors are used in a wide variety of industrial drives ...
Therefore, a DC motor otherwise a DC generator can be generally called as a DC machine. The construction of a 4pole DC generator is shown below. This generator comprises of several parts like yoke, poles pole shoes, field winding, an armature core, armature winding, commutator brushes. But the two essential parts of this device are stator as well as the rotor. Stator. The stator is an ...
multipole, threephase synchronous motor under construction. In a dc machine, the armature winding is found on the rotating member, referred to as the rotor. Figure shows a dcmachine rotor. As we will see, the armature winding of a dc machine consists of many coils connected together to form a closed loop. A rotating mechanical contact is used to supply current to the armature winding as ...
· 2DC machine are of considerable ind ustrial importance. 3 DC machine mainly used as DC m otors and the DC generators are rarely used. 4 DC motors provides a .
Construction of DC Machine. A DC machine consists of two main components: Stator and Rotor. Stator is the stationary part whereas rotor is the rotating part. Stator of DC machine consists of Yoke, Field Winding, Interpoles, Compensating Winding, Brushes and End Cover. Rotor consists of armature core, armature winding, commutator and shaft. A labeled diagram of DC machine is shown below. Each ...
The construction of DC machine can be done using some of the essential parts like Yoke, Pole core pole shoes, Pole coil field coil, Armature core, Armature winding otherwise conductor, commutator, brushes bearings. Some of the parts of the DC machine is discussed below. Construction of DC Machine Yoke. Another name of a yoke is the frame. The main function of the yoke in the machine is ...
Basic construction details about design of DC Motor or Generator.
Both the DC machines DC generator and DC motor have the same construction. Therefore, either machine can be used as a motor or a generator. So the following discussion about the construction of DC motor is equally valid for the construction of the DC generator. Also, we can entitle it as the construction of DC machine.
DC is defined as the "unidirectional" flow of current; current only flows in one direction. Voltage and current can vary over time so long as the direction of flow does not change. To simplify things, we will assume that voltage is a constant. For example, we assume that a AA battery provides, which can be described in mathematical terms as: Page 7 of 12. If we plot this over time, we see ...
for "Basic principles of DC machines" covers issues relating to DC drives in a targeted fashion. The content is first elaborated theoretically, and then consolidated in exercises. In addition to the design of the machines, their circuitry and areas of application are demonstrated in realistic projects. Technical prerequisites for setting up the circuits include: • A laboratory workbench ...
Understand the construction and principle of working of DC Machines Diagonise the failure of DC generator to build up voltage Understand the gross torque and useful torque developed by DC motor Understand the suitable methods and conditions for obtaining the required speed of DC motor Understand the Calculations of losses and efficiency of DC generators and motors Over view of .
Construction of a DC Generator A DC Generator is an electrical device which converts mechanical energy into electrical energy. It mainly consists of three main parts, magnetic field system, armature and commutator and brush gear. The other parts of a DC Generator are magnetic frame and yoke, pole core and pole shoes, field or exciting coils, armature core and windings, brushes, end ...
ELECTRICAL MACHINES ... Operating Principles and Construction What is a Transformer? A transformer is a static piece of equipment used either for raising or lowering the voltage of an AC supply with a corresponding decrease or increase in current. The use of transformers in transmission system is shown in the Figure below. Principle of Operation A transformer in its simplest form will consist ...
An equivalent circuit model for the dc machine We can construct equivalent circuit models which describe the properties noted in Section 1 above, and which can be solved to find how the dc machine will behave in a given circuit or system. The field winding is basically an inductor. If we use the linear approximation of Fig. 5, then the inductance of the winding is Lf = Nf φ If = N f 2 ℜ (11 ...
The simplest type of winding construction used in modern DC machines is the simplex lap winding. A simplex lap winding is a rotor (armature) winding consisting of coils containing one or more turns of wire with the two end of each coil coming out at adjacent commutator segments fig. (). The number of current paths in a machine is : a =mp lap winging, Where: a: number of current path in the ...
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