Power Systems — Distribution

Transformers — the reason AC won

continues from lesson 1 — values defined earlier in the course stay live here

Two coils on shared iron: voltage scales with the turns ratio, current scales inversely, power (almost) passes through untouched. This single device is why Tesla's AC beat Edison's DC:

N_{ratio} = 20

turns ratio, primary:secondary

V_{prim} := 9600 V

= 9600 V distribution feeder

V_{sec} = \frac{V_{prim}}{N_{ratio}}

= 480 V 480 V at the service entrance

I_{sec} := 200 A

= 200 A load current at the secondary

I_{prim} = \frac{I_{sec}}{N_{ratio}}

= 10 A just 10 A on the feeder side

✓ pass

abs(V_{prim} * I_{prim} - V_{sec} * I_{sec}) < 1 W

power in = power out (ideal transformer)