Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
In the conventional dc machine (with a closed continuous commutator winding on its armature), for example, full-wave rectification of the alternating voltage induced in individual armature coils is achieved by means of a commutator, which makes a unidirectional voltage available to the external circuit through the stationary carbon brushes held against the commutator surface.The armaturewindings of dcmachines are located on the rotor because of this necessity for commutation and are of the closed continuous type, known as lap and wavewindings. The simplex lap winding has as many parallel paths as there are poles, whereas the simplex wave winding always has two parallel paths. The winding connected to the commutator, called the commutator winding, can be viewed as a pseudostationary winding because it produces a stationary flux when carrying a direct current, as a stationarywindingwould. The direction of the flux axis is determined by the position of the brushes. In a conventional dc machine, in fact, the flux axis corresponds to the brush axis (the line joining the two brushes). The brushes are located so that commutation (i.e., reversal of current in the commutated coil) occurs when the coil sides are in the neutral zone, midway between the field poles. The axis of the armature mmf is then in the quadrature axis, whereas the stator mmf acts in the field (or direct) axis. Figure shows schematic representations of a dc machine. The commutator is thus a device for changing the connections between a rotating closed winding and an external circuit at the instants when the individual coil-generated voltages reverse. In a dc machine, then, this arrangement enables a constant and unidirectional output voltage. The armature mmf axis is fixed in space because of the switching action of the commutator (even though the closed armature winding on the rotor is rotating), so the commutator winding becomes pseudostationary.
Software/Application Platform Requirement: GIS solutions would primarily consist of Database and Applications software. The application package should work in LAN/WAN/Interne
What are the functions of bus interface unit (BIU) in 8086? (a) Get instructions from memory. (b) Get data from memory and I/O ports. (c) Write data to memory and I/O por
Q. What is the principle of operation of an integrating circuit? The RC integrator is typically a series RC circuit that uses the capacitor to develop its output. Since voltage
Explain LDA, STA and DAA instructions LDA copies the data byte into accumulator from the memory location particular by the 16-bit address. STA copies the data byte from the acc
What are the modes used in keyboard modes? 1. Scanned Keyboard mode with 2 Key Lockout. 2. Scanned Keyboard particular Error Mode. 3. Scanned Keyboard with N-key Rollover
Q. In a depletion MOSFET for which V P = 3 V and I DSS = 11mA, the drain current is 3mA when v DS is set at the largest value that will maintain ohmic region operation. Find v G
Q. Different kinds of high-tension fuses and low-tension fuses ? Ans: There are two kinds of fuses they are a) L.V Fuses - 1) HRC cartridge fuses. - 2) Semi enclosed re
Explain ionic polarisation. Ionic Polarisation: It takes account of the fact that while some of the atoms in a molecule contain an excess positive or negative charge that of
what is the advantage and disadvantage of back to back test of transformer
Q. Explain working of Digital Process Control? Figure shows a block diagram for microcomputer-based control of a physical process, such as a chemical plant. A slight variation
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd