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optional questions

 The use of the high speed of circuit breaker  1. Reduces the short CB. 2. Improves the system stability  3. Decrease system stability  4. Increase the short circuit current answer 2 (system stable bna rhe) Keeping in the view the cost and overall effectiveness , the following CB is best suited for capacitor bank switching. 1. vacuum 2. air blast 3.SF6 4. oil answer 1 (vacuum)

AIR CIRCUIT BREAKER

  IN AIR CIRCUIT BREAKER USES AIR TO PROTECT AN ELECTRIC CIRCUIT FROM DAMAGE CAUSED BY EXCESS CURRENT FROM AN OVERLOAD OR SHORT CIRCUIT. AFTER FAULT IS DETECTED, IT INTERRUPTS CURRENT FLOW .An arc will appear bw the contacts that have broken the circuit. Air circuit breaker use compressed air to blow out the arc and contacts are rapidly swung into a small sealed chamber.  resistance switching is normally employed in air blast CB. in this resistance high current flow which is operated.

WHAT IS REACTIVE POWER?

While the real or active power is the energy supplied to run a motor, heat a home, or illuminate an electric light bulb, reactive power provides the important function of regulating the voltage thereby to helping to move power effectively through the utility grid and transmission lines to where it is required by the load.                                                                     रिएक्टिव पावर वो पावर है जो वोल्टेज को पूरा करता है जितने की मांग होती है लोड को.   example : when we on  the हैवी लोड component it requires the component to  be stable position .THIS REQUIREMENT IS FULFILL BY REACTIVE POWER                     REACTIVE POWER IN NUMERICAL FORM.                                      Q= VIsin(phie)                                                                                                                     
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  What is feeder?                          The feeder is the subsubstation at every {power house} to supply the current by the distributors means by step down transformer to house.

transmission line based questions

                                        question 3:  Series capacitor compensation in EHV Transmission line is used to           answer:      improves the stability of the transmission line.                                        HOW?                                            xL Is reactance on T. line                                             here capacitive reactance is taking also                                             Xt =  Xl - Xc                                                                                        sss = 1/reactance                                   here reactance is decreasing and sss will be increased so steady-state stability will be limited.                                   So, for improving the stability we use a series capacitor compensation. for improving stability we use series compensator. fault der se aayega.  question 4:  corona loss on a particular system at 50Hz is 1Km/phase, the corona loss at 60Hz will be?                

questions of power system

question 1. the insulation resistance of cable of length 10KM is 1Mohm. For a length of 100Km of                         the same cable, the insulation resistance will be...                                                                                 R1L1= R2L2                                                                                                 1*10= R2*100                                                R2  =0.1Mohm ANSWER QUESTION2.  For a 500Hz frq. excitation, a 50 KM long power will be modeled as                                                                                                                                                  lemda = v/f                                                                                                            v=50*500                                                             = 25000 Km                                                                                  velocity for long transmission for lo

Substation ,distributor, Service mains....

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In this picture, You see substation (powerhouse)is in the center. To take supply #feeders are used. And feeder gives supply to the distributor to reduce power. To take this reduced power service mains is connected to the distributor. #what is the feeder? this is in a new post.

WHAT TEACHER SAYS ...

WHEN UR EXAM IS NEAR IN 2 TO 3 DAYS DO NOT READ ANY NEW MATERIAL ..KEEP REVISE YOUR LESSONS. AND DO NOT WORRY. DO NOT LOOK NEW VIDEOS IN YOUTUBE LIKE "THIS IS TEST "AND "ISSE BAHAR KA KUCH NHI AAYEGA".SO KEEP BLESSINGS. HAVE FAITH. PRAY TO GOD.

WHAT IS SUBSTATION.....

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SUBSTATION: A substation is a thing where high power comes to become short.                           like - 22kV or 33kV to 3.3kV or 6.6kV. Below u would see this in the powerhouse.                            what is a lightning arrester? A lightning arrester is a thing that grounds power if lightning falls on the substation.