Notebook

What is Signal? Signal is a time varying physical phenomenon which is intended to convey information. OR Signal is a function of time. OR Signal is a function of one or more independent variables, which contain some information. Example: voice signal, video signal, signals on telephone wires etc. Note: Noise...

The three terminals of the armature are short circuited . The machine is driven at approximately synchronous rated speed and measurements of armature short circuit currents are made for various values of field currents usually up to and above rated armature current. The machine is driven at approximately synchronous...

To obtain the open circuit characteristics the machine is driven at rated speed without the load. Readings of the line-to-line voltage are taken for various values of field current. The voltage, except in very low voltage machines, is stepped down by the means of a potential transformer. Experimental set up- OCC If...

The three-phase alternator has three single-phase windings spaced so that the voltage induced in any one is phase-displaced by 120 degrees from the other two. The voltage waveforms generated across each phase are drawn on a graph phase-displaced 120 degrees from each other. •The three phases are independent of...

The two poles of the stator winding are connected to each other so that the AC voltages are in phase, so they add.As the rotor (field) turns, its poles will induce AC voltages in the stator (armature) windings. Since one rotor pole is in the same position relative to a stator pole as any other rotor pole, both...

Angle in Electrical and Mechanical Units Consider a synchronous machine with two magnetic poles. The idealized radial distribution of the air gap flux density is sinusoidal along the air gap. When the rotor rotates for one revolution, the induced emf, which is also sinusoidal, varies for one cycle as illustrated by...

Stator and Rotor The armature winding of a conventional synchronous machine is almost invariably on the stator and is usually a three phase winding. The field winding is usually on the rotor and excited by dc current, or permanent magnets. The dc power supply required for excitation usually is supplied through a...

1 Introduction With the development of the technology and the way in which human labour is get-ting minimized and the comforts increasing tremendously the use of electrical energy is ever increasing. Basically electric power is the main source of energy for carrying out many func-tions, as it is a clean and efficient...

MCQ 4.1 The slip of an induction motor normally does not depend on (A) rotor speed (B) synchronous speed (C) shaft torque (D) core-loss component MCQ 4.2 A 220 V, 15 kW, 100 rpm shunt motor with armature resistance of 0.25 Ω, has a rated line current of 68 A and a rated field current of 2.2 A. The change in field...

·         Continuous and Discrete Time Signals We  need to study here the impact of shifting and scaling operations on the waveform of the signals, Refer in  in Oppenheim book.  classifications of signals based on different criteria like: a)      Periodic and...