Transformers and the national grid

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Question 17
Medium

This question is about a step-down transformer at an industrial substation.

Calculate the current in the primary coil.

Use the information given in Figure 1 and the equations below.

VpVs=NpNs \frac{V_p}{V_s} = \frac{N_p}{N_s} Vs​Vp​​=Ns​Np​​ VpIp=100100VsIs=VsIs V_p I_p = \frac{100}{100} V_s I_s = V_s I_s Vp​Ip​=100100​Vs​Is​=Vs​Is​

The transformer is 100% efficient.

Figure 1: Schematic diagram of a step-down substation transformer with a laminated iron core.

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Transformers and the national grid Questions

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