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!
Q. Three-phase source voltages and phase sequence?
The elementary three-phase, two-pole generator shown in Figure has three identical stator coils (aa, bb, and cc) of one or more turns, displaced by 120° in space from each other. The rotor carries a ?eld winding excited by the dc supply through brushes and slip rings. When the rotor is driven at a constant speed, voltages of equal amplitude but different phase angle will be generated in the three phases in accordance with Faraday's law. Each of the three stator coils constitutes one phase of this single generator. If the ?eld structure is so designed that the ?ux is distributed sinusoidally over the poles, the ?ux linking any phase will vary sinusoidally with time, and sinusoidal voltages will be induced in the three phases. These three induced voltage waves will be displaced by 120 electrical degrees in time because the stator phases are displaced by 120° in space. When the rotor is driven counterclockwise, Figure (a) shows the wave forms and Figure (b) depicts the corresponding phasors of the three voltages. The time origin and the reference axis are chosen on the basis of analytical convenience. In a balanced system, all three phase voltages are equal in magnitude but differ from each other in phase by 120°. The sequence of voltages in Figure 4.1.2(b), corresponding to that of Figure (a), is known as the positive sequence (a-b-c). On the other hand, if the rotor is driven clockwise, then Figure (c) shows the corresponding phasor of the three voltages; the sequence of voltages in Figure (c) is known as negative sequence (a-c-b). Notice that in positive sequence ¯Ebb lags ¯Eaa by 120°, and ¯Ecc lags ¯Ebb by 120°; in negative sequence, however, ¯ Ecc lags ¯ Eaa by 120°, and ¯ Ebb lags ¯ Ecc by 120°.
calculation of depreciation of long lived assets in times of inflation
Out of Cash Calculated by taking organization cash on hand divided by its burn rate, yielding the time period that the organization will have enough cash to cover what it wants
Differences between IAS 14 and IFRS 8 IFRS 8 requires identification of operating segments based on internal reports which are regularly reviewed by management for decision
What are the negative consequences of a company holding too much cash? A company holding so much cash would be giving up the opportunity to invest much more in income producing a
Convertible bonds can be classified into different types such as callable bonds and puttable bonds. These bonds are discussed as follows: Basics of Callable Bonds A callabl
What is meaning of Perpetuity If annuity is expected to go on forever then it is known as a perpetuity and then the above formula reduces to: Present value: A/i Perpetuit
DIY Inc. plans to raise $200,000 with a right offering. The current stock price is $100 and there are 80,000 shares outstanding. a. If DIY sets the subscription price to be $80
Q. How are the HIBOR, HSI and HSI futures related? The HIBOR and HSI are contrariwise related. So futures on HIBOR and HSI are as well inversely related. Display
Price an Asian call option with on a stock with the initial stock price $50 and volatility 30$. The strike price of the option is $52. The time to maturity of the option is 3 month
Ivan is making several entries into the general journal at the restaurant where he serves as an accountant. The main difference between entries for routine business transactions an
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