Module2 MCQ

Synchronous generators with different rotor speeds always operate in parallel at

• Same frequency
• Different  frequency
• Same power
• Same droop

The ____________ of the generating unit in a power system decides the supply of primary reserves

• frequency bias
• inertia
• rotor speed 
• nominal power

Employing the droop chracteristics, the power output of the generating units increases if the

• droop increases
• droop decreases
• inertia decreases
• inertia increases

During power imbalances, the frequency is stabilized by

• Generating units
• Generating units and frequency dependent loads
• Generating units and voltage dependent loads
• Generating units and all type of loads
  

The rate at which frequency drops (rate of change of frequency) following a fault, depends on:

• Only inertia of generating units
• Only inertia of spinning loads
• Duration of the fault
• Total inertia of the power system

Which frequency control action is taken within 30 seconds after the fault?

• Primary control
• Secondary control
• Tertiary control
• All of the choices

During alert state of the power system, insufficient reserves may lead to

• Blackout 
• Emergency state
• Normal state
• Still alert state

The rotor speed of the generator is dependent on

• Only system frequency
• Only number of poles of generating units
• Both system frequency and number of poles of generating unit
• Power rating of the generating unit

The primary control from the generating units depends on

• Droop characteristics of generating unit
• Change in system frequency
• Availability of primary reserves
• All of the choices