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!
When a machine has more than two poles, only a single pair of poles needs to be considered because the electric, magnetic, and mechanical conditions associated with every other pole pair are repetitions of those for the pole pair under consideration. The angle subtended by one pair of poles in a P-pole machine (or one cycle of flux distribution) is defined to be 360 electrical degrees,or2π electrical radians. So the relationship between the mechanical angle m and the angle in electrical units is given by
because one complete revolution has P/2 complete wavelengths (or cycles). In view of this relationship, for a two-polemachine, electrical degrees (or radians)will be the same asmechanical degrees (or radians).
In this section we set out to show that a rotating field of constant amplitude and sinusoidal space distribution of mmf around a periphery of the stator is produced by a three-phase winding located on the stator and excited by balanced three-phase currents when the respective phase windings are wound 2π/3 electrical radians (or 120 electrical degrees) apart in space. Let us consider the two-pole, three-phase winding arrangement on the stator shown in Figure.
The windings of the individual phases are displaced by 120 electrical degrees from each other in space around the air-gap periphery. The reference directions are given for positive phase currents. The concentrated full-pitch coils, shown here for simplicity and convenience, do in fact represent the actual distributed windings producing sinusoidal mmf waves centered on the magnetic axes of the respective phases. Thus, these three sinusoidal mmf waves are displaced by 120 electrical degrees from each other in space. Let a balanced three-phase excitation be applied with phase sequence a-b-c, ia = I cos ωs t ; ib = I cos(ωs t - 120°); ic = I cos(ωs t - 240°) where I is the maximum value of the current, and the time t = 0 is chosen arbitrarily when the a-phase current is a positive maximum. Each phase current is an ac wave varying in magnitude sinusoidally with time. Hence, the corresponding component mmf waves vary sinusoidally with time. The sum of these components yields the resultant mmf.
Explain Einstein relation. Einstein relation: There exists a significant relation between the diffusion constant and the mobility. It is termed as the Einstein relation and
#question. i want design of inductive coupling to transfer power @ 2 watt in air gap of 5mm radial distance..
If a permanent magnet creates the flux in a magnetic circuit, the flux exists without the need for a coil, so how does Amperes Law apply to this case? In this case the flux is
an 8 bit successive approximation adc has a resolution of 20mv. what will be its ouput analogue input of 2.17v
Consider an RLC series circuit excited by v(t) = Ve st in the time domain. Assume no initial capacitor voltage or inductive current at t = 0. Draw the transformed network in the s
Limitations of maximum power transfer theorem
Explain chemical vapour deposition method for the preparation of nanomaterial and its properties
Central Energy Conservation Fund This fund is to be set up at the Centre to develop the delivery mechanism for large-scale adoption of energy efficiency services like as perfo
Q. What do you understand by Analog to Digital conversion? What do you understand by A/D conversion? Give an explanation of any one of the following A/D techniques: (i) Su
Whose principle or law states that each point on a wave front may be considered a new wave source? Is it: w) Snell's Law x) Huygen's Principle y) Young's Law z)
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