If the field current of a paralleled AC...

If the field current of a paralleled AC...

Question 1 of 270705eccefa4bacbc34ba4d4817f

If the field current of a paralleled AC generator is increased above normal, what will be the net result to the VAR's and power factor?

Question 1 of 27070

Q

If the field current of a paralleled AC generator is increased above normal, what will be the net result to the VAR's and power factor?

🔍 Key Concepts

• Reactive power (VARs) in AC generators and what causes them to change • Effect of increasing excitation/field current on the generator’s power factor when operating in parallel • Difference between lagging and leading power factor in terms of reactive current flow (toward or from the bus)

💭 Think About

• When you increase the field current of a generator in parallel, are you making its internal voltage higher or lower relative to the bus? How does that affect reactive current flow? • Think about which condition (over‑excited or under‑excited) makes a synchronous generator behave more like an inductor (lagging) and which makes it behave more like a capacitor (leading). • How does a change in reactive power (VARs) typically show up in the power factor reading: does more VARs push PF closer to 1.0 or further away, and in which direction (lagging vs leading)?

✅ Before You Answer

• Be clear on the definition: lagging PF = current lags voltage (inductive load); leading PF = current leads voltage (capacitive load). • Remember that changing field current mainly changes reactive power (VARs), not the real kW, in a paralleled system with the governor holding load. • Before choosing, mentally match: higher excitation ↔ over‑excited ↔ ? PF direction ↔ ? change in VARs.