SOPD Frequency Control 4

Question 1

A control area's frequency bias (B) is set at -500 MW/0.1 Hz. If frequency drops by 0.2 Hz, how many MW should the area contribute to frequency response?

Accepted Answer

1000 MW

Answer

Frequency response = B × Δf in 0.1 Hz units = 500 MW/0.1 Hz × 2 (for 0.2 Hz) = 1000 MW.

Question 2

Which operating condition is considered a violation of good utility practice regarding frequency response?

Accepted Answer

Blocking or withdrawing governor response during normal operations to preserve unit life

Answer

Blocking governor response removes the unit's contribution to primary frequency response, undermining interconnection reliability and violating NERC BAL-003 obligations.

Question 3

What is 'tertiary frequency control' or 'economic dispatch' in relation to frequency management?

Accepted Answer

Longer-term redispatch of generation for economic optimization after frequency is restored

Answer

Tertiary control involves economic redispatch over longer timeframes (15 minutes to hours) to optimize generation after frequency and ACE have been restored by primary and secondary controls.

Question 4

During an over-frequency event caused by sudden large load loss, what is the appropriate operator action?

Accepted Answer

Reduce generation output or trip generation to rebalance load and generation

Answer

Over-frequency from load loss requires reducing generation (or increasing load/exports) to rebalance the system and bring frequency back to 60 Hz.

Question 5

What is the function of the Time Error Correction (TEC) program coordinated by interconnection operators?

Accepted Answer

To adjust scheduled frequency slightly above or below 60 Hz to compensate for accumulated clock error

Answer

Time Error Correction adjusts target frequency (e.g., 60.02 Hz or 59.98 Hz) to recover accumulated time error in electric clocks synchronized to power system frequency.

(SOPD) System Operator/Power Dispatching Practice Test

(SOPD) System Operator/Power Dispatching Practice Test

SOPD Frequency Control 4