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What is synchronous generator operating at a unity power factor b lagging power factor c leading power factor?
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How reverse power will occur during synchronizing?
Reverse power flow into a generator can occur during synchronization if the generator is spinning too slowly, or the voltage phase angle is lagging relative to the power system. If the generator is spinning too slowly, power from the system is used by the generator to increase its' speed. If the phase angle is lagging, an initial spike of power will flow into the generator to force it into sync with the system. Typically generator's will match system frequency very closesly, and force the phase angle to leading slightly between the generator and the system. When synchronized, an extra bump of power will flow out while the generator is torqued into phase with the system. This will avoid tripping any reverse power devices.
When you should use synchronous motor instead of capacitor for power factor correction?
Synchronous motors show some interesting properties, which finds applications in power factor correction. The synchronous motor can be run at lagging, unity or leading power factor. The control is with the field excitation, as described below:When the field excitation voltage is decreased, the motor runs in lagging power factor. The power factor by which the motor lags varies directly with the drop in excitation voltage. This condition is called under-excitation.When the field excitation voltage is made equal to the rated voltage, the motor runs at unity power factor.When the field excitation voltage is increased above the rated voltage, the motor runs at leading power factor. And the power factor by which the motor leads varies directly with the increase in field excitation voltage. This condition is called over-excitation.The most basic property of sycho motor is that it can be use as a CAPACITOR OR INDUCTOR both. Hence in turn it improves the power factor of system.The leading power factor operation of synchronous motor finds application in power factor correction. Normally, all the loads connected to the power supply grid run in lagging power factor, which increases reactive power consumption in the grid, thus contributing to additional losses. In such cases, a synchronous motor with no load is connected to the grid and is run over-excited, so that the leading power factor created by synchronous motor compensates the existing lagging power factor in the grid and the overall power factor is brought close to 1 (unity power factor). If unity power factor is maintained in a grid, reactive power losses diminish to zero, increasing the efficiency of the grid. This operation of synchronous motor in over-excited mode to correct the power factor is sometimes called as Synchronous_condenser.
What lagging or leading?
You must knew there's a sinusoidal wave form for both voltage nd current. That wave form is drawn between voltage/current nd phase angle. Unity: phase angle of voltage nd current matches, irrespective of magnitude leading: phase angle of current leads voltage by an angle lagging: phase angle of voltage leads current or current lags voltage by an angleAnswerThe terms, 'leading' and 'lagging' apply to a.c. loads. 'Leading' means that the load current leads the supply voltage, whereas 'lagging' means that the load current lags the supply voltage. 'Leading' currents occur in capacitive loads, whereas 'lagging' currents occur in inductive loads.'Leading' and 'lagging' refers to what the current is doing, relative to the voltage, never the other way around.
Why Power factor becomes less lagging when capacitor is switched on?
Because capacitor withdraw leading current from source and net resultant become less lagging.
What determines leading or lagging power factor?
underdampedAnswerA lagging power factor describes a situation in which the load current is lagging the supply voltage. This describes an inductive load, such as a motor, etc.
When synchronus generator is supplying active and reactive power it is operating at leading or lagging power factor?
A synchronous generator is operating at lagging power factor (positive P & Q) when it is supplying P & Q to the system. P & Q are positive which means that they are flowing away from the bus where the generator is connected (overexcited case). On the other hand, it is operating at leading power factor when it is supplying P and absorbing Q. The sign of Q is negative which means that it is flowing towards the generator bus (underexcited case).
Would you compare generator current to line voltage to determine if your leading or lagging?
It's always the current that determines 'leading' or 'lagging' -i.e. the angle by which the current leads or lags the voltage.
What is the Reactive power in a capacitive modeand inducitive mode?
Generators can be required to generate real and reactive power. When operating in a leading mode, the generator is generating real and leading reactive power (inductive power). This means the generator is "sucking in VARS", which will pull down the terminal voltage similar to an inductor. It can also be operated in a lagging mode, which means it is generating real and lagging reactive power (capacitive power). The generator, then, is "pushing out VARS" like a capacitor, which will cause the terminal voltage to increase. Generators can only create so many leading and lagging VARs; in general lagging VARs are limited by the automatic voltage regulator output capabilities; leading vars are limitted by how much heat the stator can dissipate.
What happens if the synchronous motor exceeds its load capacity?
If load on a generator is greater than the generator can provide, the generator will begin to slow down. If it slows down too much, it will lose synchronism.
Which strand (leading or lagging) will have the okazaki fragments?
The lagging strand.
How do you draw phase diagram for transformer operating at load with lagging PF and leading PF?
In order to draw the phase diagram for transformer operating at load with lagging PF and leading PF, you will need to know the equation for the transformer being load free. This constant will help you with the load bearing equation of Np/Ns=Vp/Vs=Is/Ip.
Leading and lagging power factor?
The terms, 'leading' and 'lagging' refer to what the load current is doing, relative to the supply voltage (Phase difference) -never the other way around. If the current is leading the voltage, then the power factor is 'leading'; if the current is lagging the voltage, then the power factor is 'lagging'.
Current calculation when parallel operating generators?
Yes and no. One generator may be operating in the leading VAR region, and the other may be operating in the lagging VAR region. This would result in reactive current effectively circulating between the two generators.If you are talking about active (real) power, this should not happen, and will cause protective equipment to trip. Generators should generate real power, not consume it.
Where does ssb protein bind on lagging strand or on leading strand?
ssb protein bind to the lagging strand as leading strand is invovled in dna replication and lagging strand is invovled in okazaki fragment formation
Compare the leading and lagging strands during replication?
the leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction
How reverse power will occur during synchronizing?
Reverse power flow into a generator can occur during synchronization if the generator is spinning too slowly, or the voltage phase angle is lagging relative to the power system. If the generator is spinning too slowly, power from the system is used by the generator to increase its' speed. If the phase angle is lagging, an initial spike of power will flow into the generator to force it into sync with the system. Typically generator's will match system frequency very closesly, and force the phase angle to leading slightly between the generator and the system. When synchronized, an extra bump of power will flow out while the generator is torqued into phase with the system. This will avoid tripping any reverse power devices.
There is a y shaped replication fork on each side of each replication bubble what are the sides of the replication fork called?
One is known as the Leading strand, and the other is known as the Lagging strand.
