Consider the following statements: The calculation performed using short line approximate model instead of nominal-π model for a medium length transmission line delivering lagging load at a given receiving end voltage always results in higher: 1. Sending end current 2. Sending end power 3. Regulation 4. Efficiency Which of these statements are correct?

Option 1 : 1 and 2 only

For a transmission line of capacitance is considered, then-current drawn by the line is some of the load current & capacitive current. Most of the load current is inductive, so it will be lagging.

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The phasor diagram for the above circuit diagram would be,

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Hence I_S automatically becomes less than I_R i.e. I_S < I_R

If no capacitance is considered for the line, then sending end current and Receiving end current will be equal, i.e. I_S = I_R, which means sending end current is increased.

If sending end current is an increase, then automatically sending end power is increased.