• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar

How Engineering Works

  • Home
  • About Us
  • Electrical Engineering
    • Interview Questions
  • Privacy Policy
  • Disclaimer
  • Contact Us
  • Blog

Why Power Plant Capacity Rated in MW and not in MVA?

November 17, 2017 by Dollar

DWQA Questions › Category: (EE) Power System › Why Power Plant Capacity Rated in MW and not in MVA?
0 Vote Up Vote Down
Dollar asked 5 years ago
3 Answers
0 Vote Up Vote Down
Bhisham answered 5 years ago

For the following reasons, a Power plant capacity rating may be expressed in MW instead of MVA.
In a Generating station, the prime mover (Turbine) generates only and only active power. That’s why we rated a power plant capacity in MW instead of MVA. Its mean no matter how large your generator is, but it depends on the capacity of the  engine (Prime mover/Turbine) I.e. a 50MW turbine connected to a 90MVA alternator in a power plant will generate only 50MW at full load. In short, a power plant rating is specified in terms of prime mover /Turbine (Turbine rating may be seen by nameplate rating which is in MW or Horsepower (HP) not in MVA) and not by the alternator set coupled to it.

0 Vote Up Vote Down
brno answered 5 years ago

MVA is the apparant power, MW is the real power and, MVAR is reactive power. MW describes the actual power that can be supplied to the load and MVA includes both the power supplied to the load AND the power that recirculates between the power plant and the load (volts*amps).
Watt : Is For Real Power
Real Power = apparent power * Power Factor (P.F)
And Power Plants have resistive Loads So it’s rated in MW.

0 Vote Up Vote Down
Rubi answered 5 years ago

MW describes the actual power that can be supplied to the load (voltsampscos theta).
MVA includes both the power supplied to the load AND the power that recirculates between the power plant and the load (volts*amps).
Because power plants have to supply both reactive and resistive loads, the two ratings describe a different capability. Most importantly, all of the power electronic devices, transformers, and switchgear in the system have to be sized against the MVA rating, not the MW rating. This is because reactive loads will cause currents to flow that circulate between phases (as opposed to active loads, which consume power from the utility) but don’t actually deliver active power to the load.

Primary Sidebar

Related Questions

  • What is an earthing transformer? asked by admin
  • What is real, reactive, and apparent power? asked by admin
  • List of equipment in substation asked by
  • What do you mean by Earth electrode? asked by admin

INTERVIEW QUESTIONS

MCQ or Objective





Recommended Post

MCQs on Transmission and Distribution

MCQs on Engineering Materials

MCQ on Measuring Instruments – 1

MCQs on Transformer

Electric current

Categories

  • Electrical Articles (19)
  • Electrical MCQ (75)
  • Electrical Questions (11)
  • Interviews Questions (7)
  • IQ Test (1)
  • Uncategorized (12)

Join Our Whatsapp Group


About Us | Privacy Policy | Disclaimer


Copyright@2017-2022