A two-phase load draws the following phase currents: i1

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A two-phase load draws the following phase currents: i₁ (t) = I_m sin(ωt – φ₁ ), i₂ (t) = I_m cos(ωt – φ₂). These currents are balanced if φ₁ is equal to

1. – φ₂
2. φ₂
3. π - φ₂
  2
4. π + φ₂
  2

Correct Option: D

i₁ (t) = I_m sin (ωt – φ₁)
= I_m cos [90° – (ωt – φ₁)
= I_m cos(°t – φ₁ – 90°)
i₂(t) = I_m cos(ωt – φ₂)
Angle difference between two currents should be – 180° (or) 180° for balanced
– φ₁ + φ₂ – 90°= – 180° ⇒ φ₁ = 90° + φ₂