Answer Posted / sath
DC machines can be classified as self-excited, separately
excited, permanent magnet (PM), and brushless.
AC machines can be classified as induction, wound rotor,
and synchronous.
Self-excited machines can be further classified as shunt,
series, and compound. Compound machines can be further
classified as cumulative and differential. Cumulative and
differential machines can be further classified as long
shunt and short shunt. As you can see, there are a variety
of electrical configurations for a DC machine.
Induction motors can be further classified as 3-phase and
single-phase. A 3-phase induction motor can be further
classified as delta wound or wye wound. Single-phase
motors can be further classified as split phase (Fig. 3),
capacitor start, capacitor start/capacitor run, shaded
pole, repulsion start, and universal. As you can see, there
are several varieties of AC motors.
Common terms you will hear discussed with DC motors include
commutator, brushes, counter electromotive force (EMF),
torque, speed regulation, and speed-torque characteristic
curves.
Common terms you will hear discussed with AC motors include
frequency, synchronous speed, and slip.
In d.c. motor speed is depended on field strength of the
machine.
In a.c. motor speed is depended on frequency of the machine.
In d.c. motor torque is depended on armature current and
field flex.
In a.c. motor torque is depended on slip.
Is This Answer Correct ? | 29 Yes | 3 No |
Post New Answer View All Answers
What is sensitivity of a measurement?
What is the effect on power factor, shown by a trivector meter; incase of reverse phase sequence. If the power factor of a system is lag what meter will show in case of reverse phase sequence connected to the meter. and What in case of lead.
11kV capacitor bank of rating 2.4KVAR, is charged with protective relays of only over current & Earth fault &.......without Over Voltage, Under Voltage & Neutral Displacement Relay. Is it advisable??
In radial network the source is fed from 1 end both ends at central
what is the purpose of silicon dropper used in battery charger?
Hi, My plant daily consumption is calculated as 3.8MWH but my supplier has sanctioned an power of 2.6MW per day. how can i equal or distinguish this two factors
what is differentila pilot supervision in the incomer control panel in the power station?
What is the effect of solar radiation on the design of an Isolated Phase Busduct?
we have earthmat at 110KV substation.we would like to take earth resistance.b some says that by connecting earth megger terminals (C1,P1) at middile point of earthmat (at riser) will cause voltage gradient at other earthmat nods and dont get exat earth resistance.when connecting at end nods will get exat value . is it correct .please explain
WHAT IS IM (INDEX OF MOUNTING )IN MOTORS
Why do we need interlocking in a HT metering or Ring main unit switchgear?
IN SINGLE PH TRANSFORMER IF LEKAGE IMPEDANCE DROP IS NEGLECTED ,THE FLUX IN THE MAGNETIC CORE and the lekage flux linking a winding are a)proportional to the applied v to the winding i respectively.
Can we use BS 6651 and BS EN 62305 standards for computer room lightning ptotection in substation?
if there are six generators (3 gas CATT, one Jenbacher o1 MW each, and two nos Diesel 01 no 01 mw other 0.65mw EDGs ( say), 3 CAtt gas set have identical pole pitch,01mw EDG and Jenbacher gas Set have different pole pitch, how their power connection can be done to connect a common bus bar during installation. in short, how different pole pitched generators power connection can be done to connect a common busbar system through generators incomer ACBs.