<p style="text-align:justify"><img alt="" src="https://edupmquestionhelp.s3.ap-south-1.amazonaws.com/hint/uploads/images/16257485191625748519.jpg" style="height:424px; width:800px" /></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px">Figure 7.45 shows a single line diagram of a portion of an interconnected power system. The loads connected to all the three buses are tabulated below:</span></p>

<p style="text-align:justify">&nbsp;</p>

<p style="text-align:justify">&nbsp;</p>

<p style="margin-left:48px; text-align:center">&nbsp;</p>

<table cellspacing="0" class="MsoTableGrid" style="border-collapse:collapse; border:none; margin-left:151px; width:900px">
	<caption>
	<p><span style="font-size:18px"><strong>Table 7.22: Maximum Normal Load Current on the Buses</strong></span></p>
	</caption>
	<tbody>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:174px">
			<div style="text-align:center"><span style="font-size:28px">Bus</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:176px">
			<div style="text-align:center"><span style="font-size:28px">Load in MW</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:174px">
			<div style="text-align:center"><span style="font-size:28px">A</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:176px">
			<div style="text-align:center"><span style="font-size:28px">200 MW at 0.85 pf lag</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:174px">
			<div style="text-align:center"><span style="font-size:28px">B</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:176px">
			<div style="text-align:center"><span style="font-size:28px">200 MW at 0.85 pf lag</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:174px">
			<div style="text-align:center"><span style="font-size:28px">C</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:176px">
			<div style="text-align:center"><span style="font-size:28px">120 MW at 0.85 pf lag</span></div>
			</td>
		</tr>
	</tbody>
</table>

<p style="margin-left:48px; text-align:justify">&nbsp;</p>

<p style="margin-left:48px; text-align:justify">&nbsp;</p>

<p style="margin-left:48px; text-align:justify"><span style="font-size:14px">The fault currents for triple line fault at different locations are tabulated as follows:</span></p>

<p style="margin-left:48px; text-align:center">&nbsp;</p>

<p style="margin-left:48px; text-align:center">&nbsp;</p>

<p style="margin-left:48px; text-align:center">&nbsp;</p>

<table cellspacing="0" class="MsoTableGrid" style="border-collapse:collapse; border:none; margin-left:48px; width:900px">
	<caption>
	<p><strong><span style="font-size:18px">Table 7.23: Fault Currents for Triple Line Fault</span></strong></p>
	</caption>
	<tbody>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">Fault Location</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">Fault Current in Primary of CT<sub>1</sub> in Amp</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">Fault Current in Primary of CT<sub>2</sub> in Amp</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">Fault Current in Primary of CT<sub>3</sub> in Amp</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">Fault Current in Primary of CT<sub>4</sub> in Amp</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">Fault Current in Primary of CT<sub>5</sub> in Amp</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:1px solid black; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">Fault Current in Primary of CT<sub>6</sub> in Amp</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">F<sub>1</sub></span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">4260</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">635</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">635</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">635</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1270</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1270</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">F<sub>2</sub></span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">635</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">4260</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">635</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">635</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1270</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1270</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">F<sub>3</sub></span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">2820</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">F<sub>4</sub></span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">2820</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">F<sub>5</sub></span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">2820</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1410</span></div>
			</td>
		</tr>
		<tr>
			<td style="border-bottom:1px solid black; border-left:1px solid black; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">F<sub>6</sub></span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">977</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">977</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">977</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">977</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1955</span></div>
			</td>
			<td style="border-bottom:1px solid black; border-left:none; border-right:1px solid black; border-top:none; vertical-align:top; width:86px">
			<div style="text-align:center"><span style="font-size:28px">1812</span></div>
			</td>
		</tr>
	</tbody>
</table>

<p style="margin-left:48px; text-align:center">&nbsp;</p>

<p style="margin-left:48px; text-align:justify">&nbsp;</p>

<p style="margin-left:48px; text-align:justify">&nbsp;</p>

<p style="margin-left:48px; text-align:justify"><span style="font-size:14px">The other data required is as follows:</span></p>

<p style="margin-left:48px; text-align:justify">&nbsp;</p>

<ul>
	<li style="text-align:justify">
	<p><span style="font-size:14px">All the phase relays in the system shown are voltage-controlled normal inverse IDMT overcurrent relays such that their plug-setting reduces to 40 % of set value when voltage collapses below 70 % of rated voltage. The setting range for plug-setting is </span></p>
	</li>
</ul>

<p style="margin-left:96px; text-align:justify"><span style="font-size:14px">50-200 % of 1 amp and for TMS is 0-1 in steps of 0.05.</span></p>

<ul>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Assume that 10 % of generated power is consumed by the auxiliaries.</span></p>
	</li>
	<li style="text-align:justify">
	<p><span style="font-size:14px">Allow for 10 % overload while deciding plug-setting.</span></p>
	</li>
</ul>

<p>&nbsp;</p>

<p style="text-align:justify"><span style="font-size:14px"><strong>TMS of phase relays R<sub>1</sub>/R<sub>2</sub> shall be set at</strong></span></p>