In d.c. machine iron losses occur in
WebFeb 24, 2012 · These losses occur due to current flowing in stator and rotor windings. As the load changes, the current flowing in rotor and stator winding also changes and hence these losses also changes. Therefore these losses are called variable losses. The copper losses are obtained by performing blocked rotor test on three phase induction motor. WebIn a dc machine mechanical losses occur due to (a) air resistance of rotation to armature and fan. (b) brush friction. (c) bearing friction. (d) all of the above. SHOW ANSWER 17. In a dc machine, mechanical losses are primarily function of (a) voltage. (b) current. (c) speed. (d) none of these. SHOW ANSWER 18.
In d.c. machine iron losses occur in
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WebNov 30, 2015 · The losses that occur in a DC Machine is divided into five basic categories. The various losses are Electrical or Copper losses (I 2 R losses), Core losses or Iron … WebOct 23, 2024 · Although it is well known that the magnetic properties of electrical steel can be deeply affected by the cutting process, it is still not clear how to accurately evaluate these effects on a prototyped machine on its final shape, especially at a high frequency or a high power rating. This research provides a more practical method for accurate measurement …
WebAug 1, 2024 · Iron loss is one of the major losses in electrical machines. The accurate prediction of the iron loss is essential for the electromagnetic and thermal design of … WebThe condition for maximum efficiency for a D.C. generator is. A. Eddy current losses = stray losses. B. Hysteresis losses = eddy current losses. C. Copper losses = 0. D. Variable losses = constant losses. View Answer.
WebSep 26, 2016 · Mechanical losses are divided into bearing, friction loss and windage loss. The losses occurring in moving parts of the machine and the air present in the machine … WebJan 22, 2024 · In the DC motor, iron losses occur in armature because the armature core is made of iron and it rotates in a magnetic field. Hence a small current gets induced in the …
WebIn case of DC machine iron loss occurs in armature core and in order to reduce eddy current losses armature core is usually laminated. As we know in case of transformer that for constant flux density hysteresis loss is proportional to frequency and Eddy current loss is proportional to square of frequency.
WebMay 31, 2015 · The losses that occur in a DC Machine are divided into five basic categories. Electrical or Copper losses (I2R losses): The copper losses are the winding losses taking place during the current flowing through the winding. These losses occur due to the resistance in the winding. earth\u0027s crust state of matterWebwhere. P i0 = no-load core (iron)-loss (constant). P wf = windage and friction loss (constant) (2) Variable losses, where. P c = 3I 2 R, the copper-loss (factor 3 will not be present in a dc machine); R is the resistance parameter of the machine.. P st = stray-load loss (copper + iron) = αI 2 (Here the stray-load loss is assumed proportional to the square of the load … earth\\u0027s cureMechanical lossesoccur in the moving parts of the DC machine due to friction and windage. These losses are also called rotational losses. The mechanical losses depend upon the speed of the machine. In a DC machine, two types mechanical losses occur, which are as follows 1. Friction Loss– such as … See more The iron lossesoccur in the armature core of the DC machine since the armature core is subjected to the magnetic field reversal i.e. changing magnetic field. The core losses are of two … See more The copper lossesin a DC machine occur in the various windings of the machine due to currents flowing in them. In a typical DC machine, following copper losses occur ArmatureCopperLoss=Ia2Ra … See more The armature core of DC machine is subjected to magnetic field reversal when it passes under successive poles. An energy loss takes … See more When the armature of DC machine rotates in the magnetic field produced by the poles, an emf is induced in the core and due to this induced … See more earth\u0027s cure promo codeWebThe power losses occur due to the friction between rotating armature and air is known as windage loss or air friction loss. This is because the armature needs to be pushed against the wind to rotate. Hence, total losses of the DC generator can be defined as follow: Total Losses = Variable Losses + Constant Losses Where: ctrl h no wordWebMar 16, 2024 · The losses occur in the machine mainly are: Iron losses in the core Friction and windings losses Armature copper loss. Since the no load mechanical output of the machine is zero in Swinburne's test, the no load input power is … ctrl + hoiWebOct 18, 2024 · What are the components of iron loss in a dc machine and in which part of the machine it occurs? Answer. Iron loss consists of hysteresis and eddy current losses caused by changing flux densities in the iron core. Hysteresis loss incurs in revolving armature and teeth of a dc machine. earth\u0027s cureWebFeb 26, 2024 · Mechanical Losses in DC Machine: The losses associated with mechanical friction of the machine are called mechanical losses. These losses occur due to friction in … earth\u0027s crystalline grid