Hi.. Everyone , in my last post I have provided the basic information about the energy sources.Actually the energy sources we have discussed are dc sources in addition to those there are some sources where the voltage and current may vary with time sinusoidally , exponentially etc., and the sources are called the Alternating sources.
Basically the types of alternating sources depends on the type of input periodic signal we are giving to the source.
The wave forms can be represented by
f(t) = f(t+nT)
f(t) = f(t+nT)
Here n is an integer and T is the time period of the periodic wave form.
Out of the periodic functions , the sinusoidal function being the most common and being widely used.
Now let us discuss some important factors regarding the periodic sine wave.
1.Peak value:
It is defined as the maximum value of the sine wave either during positive half cycle or negative half cycle.
It is defined as the maximum value of the sine wave either during positive half cycle or negative half cycle.
Vm is the peak value of sinusoidal voltage wave .
Im is the peak value of sinusoidal current wave.
Generally sinusoidal periodic wave form is represented as.
V=Vm Sinwt.
I=Im Sinwt.
2.Instantaneous value:
It is the value of the periodic sine wave at any instant of the cycle. This value will be different at different points of the wave form.
It is the value of the periodic sine wave at any instant of the cycle. This value will be different at different points of the wave form.
3.Average value:
Generally it is the average value of the sine wave during its cycle but the average value of a sine wave during its full cycle will be zero because of positive and negative half cycles. It is calculated only for the either anyone of the half cycle.
Generally it is the average value of the sine wave during its cycle but the average value of a sine wave during its full cycle will be zero because of positive and negative half cycles. It is calculated only for the either anyone of the half cycle.
Vav= 2Vm/π
Vav = 0.637Vm.
4.RMS Value:
As we discussed earlier ,the effect of sine wave over a complete cycle is zero. So in order to get it's effective value we are considering in terms of heating power and this is called Root Mean Square Value or RMS Value.
Vrms= Vm /√2.
Vrms= 0.707 Vm.
5.Form Factor
It is defined as the ratio of RMS value to the average value .
The basic requirement of form factor is , on some cases if the two alternating waves having same peak values and same frequency may look different . In these cases their configurations change. Form factor represents this change in configuration of periodic waveforms where the frequencies and amplitudes are same.
4.RMS Value:
As we discussed earlier ,the effect of sine wave over a complete cycle is zero. So in order to get it's effective value we are considering in terms of heating power and this is called Root Mean Square Value or RMS Value.
Vrms= Vm /√2.
Vrms= 0.707 Vm.
5.Form Factor
It is defined as the ratio of RMS value to the average value .
The basic requirement of form factor is , on some cases if the two alternating waves having same peak values and same frequency may look different . In these cases their configurations change. Form factor represents this change in configuration of periodic waveforms where the frequencies and amplitudes are same.
Form Factor (FF) = Vrms /Vav
FF= 0.707Vm/0.637Vm
FF= 1.11
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