If two alternators are operating in...

Question 1 of 270705eccefa4bacbc34ba4d481af

If two alternators are operating in parallel, what will change if each alternator's field excitation is changed in opposite directions (one alternator's field current increasing, while the other is decreasing)?

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Question 1 of 27070

🔍 Key Concepts

• Effect of field excitation on alternator terminal voltage and power factor • Difference between active (real) power and reactive power sharing when generators are in parallel • Role of speed/governor vs excitation in controlling generator outputs

💭 Think About

• When two alternators are in parallel and you change only the field currents (not the governors), which quantity are you actually controlling: voltage, frequency, or something else? • Which type of power (active vs reactive) is mainly influenced by field excitation and power factor? • Does changing excitation in opposite directions make sense for changing frequency, or does that more directly affect how the load’s reactive component is shared between machines?

✅ Before You Answer

• Confirm that frequency and phase sequence are primarily controlled by prime mover speed and connection, not excitation • Recall that active (real) power sharing is mainly adjusted with governor/speed setting, not field current • Verify that changing field excitation alters terminal voltage and reactive power flow between paralleled alternators