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How capacitor and resitor in a circuit effect the phase of input voltage?
A capacitor and a resistor has no effect on the supply voltage; however, this particular load combination will cause the load current to lead the supply voltage by some angle termed the 'phase angle'.
Define the term regulation as applied to dc power supply?
change in load voltage or output voltage changes in load current
What is the power factor of an resititive load?
Power factor is the cosine of the phase angle between voltage and current. In a resistive load, current is in phase, i.e. with a phase angle of 0 degrees, with respect to voltage. Cosine (0) is 1.
What is no load tap changing in transformer?
It changes the tap while it is operation (hence "on load"). This allows real-time voltage regulation for the transformer secondary (as load picks up, causing the voltage to sag, the LTC can tap up, increasing the voltage).
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.
Effect of changing load on alternator?
by changing load its terminal voltage changes.
What is the principle cause of voltage variation?
Changes in load.
Why is the voltage level not constant in electrical power transmission?
Changes in load causes the load current to change, resulting in changes in voltage drop along conductors. This means that the 'receiving end' voltage will vary.
How capacitor and resitor in a circuit effect the phase of input voltage?
A capacitor and a resistor has no effect on the supply voltage; however, this particular load combination will cause the load current to lead the supply voltage by some angle termed the 'phase angle'.
Define the term regulation as applied to dc power supply?
change in load voltage or output voltage changes in load current
What is the power factor when the current and voltage are in phase?
The power factor of a load is the cosine of the angle by which the load current lags or leads the supply voltage. So if they are in phase (phase angle is zero), then the power factor must be unity (1).
In a purely resistive ac circuit the current and voltage?
Voltage and current will be in phase for a purely resistive load. As a load becomes more inductive or capacitive, the phase angle between voltage and current will increase.
What is lead and lag angles?
Leading angle means that the current lead voltage by 90 degree,which implies a capacitve load. while,lagging angle mean when the current lag the voltage by 90 degree or when the voltage lead the current by 90 degree.which implies an inductive load.
What is the effect of changing the firing angle?
Changing the firing angle affects the conduction angle of the AC voltage waveform supplied to the load in AC-DC converters like controlled rectifiers. By altering the firing angle, the average output voltage and hence the power delivered to the load can be controlled, affecting the speed or intensity of the load, like in motor control applications.
What does zero leading power factor mean?
A 'leading' power factor indicates that the load current is leading the supply voltage. Since power factor is the cosine of the angle by which the load current either leads or lags the supply voltage (i.e. the load's phase angle), a cosine of 0 corresponds to a phase angle of 90 degrees. So, a power factor of 0 (leading) indicates that the load current is leading the supply voltage by 90 degrees, which means that the load must be purely capacitive.
What is the power factor of an resititive load?
Power factor is the cosine of the phase angle between voltage and current. In a resistive load, current is in phase, i.e. with a phase angle of 0 degrees, with respect to voltage. Cosine (0) is 1.
What is extinction angle control?
extinction angle control is a scheme of forced commutation for power factor improvement in phase controlled convertors/rectifiers. In this scheme the firing angle is adjusted in order to get the desired output or load voltage. By varying the value of extinction angle we can get the desired load voltage and current waveform.......submitted by abhimanyu(sunny)
