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1. Input Displacement Factor (DSF):
$$DSF =\cos \alpha$$
2. Input Power Factor (PF):
$$P F=\left(\frac{I_{1}}{I_{\mathrm{rms}}}\right) \cos \phi_{1}$$
$$=\left(\frac{2 \sqrt{2} I_{d}}{\frac{\pi}{I_{d}}}\right) \cos \alpha P F=\frac{2 \sqrt{2}}{\pi} \cos \alpha$$
3. D.C. Voltage Ratio:
$$r=\frac{\frac{1}{\pi} \int_{\alpha}^{(\pi+\alpha)} E_{m} \sin \omega t \cdot \mathrm{d}(\omega t)}{\frac{1}{\pi} \int_{0}^{\pi} E_{m} \sin \omega t \cdot \mathrm{d}(\omega t)}, r=\cos \alpha$$
4. Input Current Distortion Factor:
$$=\frac{I_{1}}{I_{\mathrm{rms}}}=\frac{2 \sqrt{2} I_{d}}{\pi \cdot I_{d}}=\frac{2 \sqrt{2}}{\pi}$$
5. Input Harmonic Factor $\left(\boldsymbol{I}_{H}\right)$:
We know that
$$ I_{H}=\frac{\left(I_{\text { rms }}^{2}-I_{1}^{2}\right)^{1 / 2}}{I_{1}} $$
Substituting the values of $I_{\mathrm{rms}}$ and $I_{1}$
$$I_{H}=\frac{\left[I_{d^{2}}-\left(\frac{2 \sqrt{2} I_{d}}{\pi}\right)^{2}\right]^{1 / 2}}{2 \sqrt{2} I_{d} / \pi}=\frac{\left[I_{d^{2}}-\frac{8 I_{d^{2}}}{\pi^{2}}\right]^{1 / 2}}{2 \sqrt{2} I_{d} / \pi}$$
$$=\frac{\left[\frac{\pi^{2} I_{d^{2}}-8 I_{d^{2}}}{\pi^{2}}\right]^{1 / 2}}{2 \sqrt{2} \mathrm{Id} / \pi}$$
$$=\left[\frac{\pi^{2}-8}{8}\right]^{1 / 2}$$
$$ I_{H}=\left[\frac{\pi^{2}}{8}-1\right]^{1 / 2}$$
6. Voltage Ripple Factor $\left(k_{\mathrm{V}}\right)$:
We have the equation for $k_{V}$ as
$$k_{V}=\frac{\sqrt{E_{\mathrm{dc} \operatorname{ms}}^{2}-E_{\mathrm{dc}}^{2}}}{E_{\mathrm{dc}}}=\frac{\left[\frac{E_{m}^{2}}{2}-\left(\frac{2 E_{m}}{\pi} \cos \alpha\right)^{2}\right]^{1 / 2}}{\frac{2 E_{m}}{\pi} \cos \alpha}$$
$$=\frac{E_{m}\left[\frac{1}{2}-\frac{4}{\pi} \cos ^{2} \alpha\right]^{1 / 2}}{2 E_{m} \cos \alpha / \pi}=\frac{\pi\left[\frac{1}{2}-\frac{4}{\pi^{2}} \cos ^{2} \alpha\right]^{1 / 2}}{2 \cos \alpha}$$
$$=\frac{\pi\left[\frac{\pi^{2}-8 \cos ^{2} \alpha}{2 \pi^{2}}\right]^{1 / 2}}{2 \cos \alpha}=\left[\frac{\pi^{2}-8 \cos ^{2} \alpha}{2 \cos ^{2} \alpha}\right]^{1 / 2}$$
$$k_{V}=\left(\frac{\pi^{2}}{8 \cos ^{2} \alpha}-1\right)^{1 / 2}$$
7. Active Power Input $(P_i)$: Only the fundamental component contributes to the mean a.c. input power and the mean power as the harmonic components of current is zero.
Therefore, the mean a.c. input power in a given line is given by:
$$ \begin{aligned} P_{i}=& \text { RMS line voltage } \times \text { RMS fundamental component of current } \\ & \times \text { displacement factor. } \end{aligned} $$
$$=E_{\mathrm{rms}} \times I_{1} \times \cos \alpha$$ $$=E_{\mathrm{rms}} \times \frac{2 \sqrt{2} I_{d}}{\pi} \cos \alpha=\frac{2 E_{m}}{\pi} I_{d} \cos \alpha$$
8. Reactive Power Input $(Q_i)$: Reactive power input is given by $$Q_{i}=E_{\mathrm{rms}} \cdot I_{1} \sin \alpha=\frac{2 E_{m}}{\pi} I_{d} \sin \alpha$$