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For clarification, the correct symbols are 'MV.A' and 'MW' -where a capital 'M' represents 'mega'. A lower case 'm' stands for 'milli' -quite a difference. And the symbols for ampere and volt are an upper case A and an uppercase V.
When an electric current flows through a load, the temperature of the load increases above ambient temperature, and energy is therefore lost to the surroundings through heat transfer. This represents a permanent loss of energy from the circuit. The rate at which this energy is lost is called the true power of the circuit, measured in watts.
At the same time, whenever current flows, a magnetic field is set up around the conductor. As the current increases in value during the first quarter-cycle, this field expands and energy is stored within that field. During the next quarter-cycle, as the current reduces in value, the energy stored in the magnetic field is returned to the circuit. So, while there is movement of energy, there is no net loss of energy from the circuit. The rate at which this energy transfer is taking place is called the reactive power of the circuit, measured in reactive volt amperes. (A similar thing happens in capacitive circuits, although the energy is stored/returned in an electric, rather than in a magnetic, field).
The vector sum of true power and reactive power is called the apparent power of the circuit, measured in volt amperes. That is:
(Apparent Power)2 = (True Power)2+ (Reactive Power)2
(Technically, there is absolutely no reason why true power, reactive power, and apparent power can't all be measured in watts -it is only traditional to use different units!)
It is very easy to measure the apparent power of a circuit, because it is the product of the voltage applied to the load and the current flowing through it -and we could use a voltmeter and an ammeter to determine these values. It is rather more difficult to measure the true power because the voltage and the current must be multiplied by the load's power factor, which is not necessarily known. Nevertheless, it can be measured directly, using a wattmeter.
Wiki User
∙ 11y ago
Wiki User
∙ 10y agonot affected in powerfactor then u easily specified in MVA
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A transmission line has 30 megawatts and 40 megavars what is the megavolt amps load on the line?
By definition, MVA is equivalent to the vector sum of MW and MVAR: MVA^2 = MW^2 + MVAR^2 = 2500 MVA = 50
How do you convert MVA into MW?
You would have to know the Power Factor, normally designated PF. MVA x PF = MW. If the PF is unity then MVA = MW. A PF of UNITY suggest the load is purely resistive with neither capacitive nor inductive components in the load or source. Of course this can mean such components have been balanced artificially.
How much power in a 15000 kva transformer?
The power in a 15 MVA (15000 KVA) transformer depends on the power factor. You did not specify the power factor, so I will assume a power factor of 0.92. Simply multiply MVA by PF and you get 13.8 MW.
What is difference between 500MW boiler 660MW boiler?
500 MW Boiler is sub-critical Boiler which generates steam at pressure lower than the critical pressure ie below 221.2 kg/sqcm. where as the 660 MW boiler is super critical boiler which operates steam pressure above critical pressure.
How many MW is 25KW?
1 kw = 0.001 mw 25 kw = 0.025 mw
What does mva stand for in the turbo generator field?
There are two concerns here regarding loading on transformers of this size. First is the difference between MVA and MW. MW is just real power -- watts. MVA is total power which includes real power (MW) and reactive power (MVAR).--- http://en.allexperts.com/q/Electric-Power-Utilities-2405/operation-limit-oof-power.htm
What does mva mean in electrical terms?
MVA is the apparent power. MVA=( MW+ MVAr)1/2
A transmission line has 30 megawatts and 40 megavars what is the megavolt amps load on the line?
By definition, MVA is equivalent to the vector sum of MW and MVAR: MVA^2 = MW^2 + MVAR^2 = 2500 MVA = 50
How do you convert mw to mva?
You would have to know the Power Factor, normally designated PF. MVA x PF = MW. If the PF is unity then MVA = MW. A PF of UNITY suggest the load is purely resistive with neither capacitive nor inductive components in the load or source. Of course this can mean such components have been balanced artificially.
A transmission line has 30 mw and 40 mvar flowing what is the mva flow on the circuit?
MVA= square root of (MW2 + MVAR2 )
How many mega volt ampere are there in a 1 mega watt generator?
MVA(Mega volt ampere) is the cos component of MW. So one should know the power factor of the system for conversion from MVA to MW.
How is a 100 MVA transformer cooled?
Large transformers are filled with oil which circulates to a radiator to get rid of excess heat. A 100 MVA transformer should waste about 1 MW of power on full load, 0.5 MW on no load.
How do you calculate MVAR with mw and mva?
mw/mva=power factor reactive power(Q)=I2XL or E2/XL where XL= REACTANCE apparent power = square root of (MW2 + MVAR2 )
How do you convert MVA into MW?
You would have to know the Power Factor, normally designated PF. MVA x PF = MW. If the PF is unity then MVA = MW. A PF of UNITY suggest the load is purely resistive with neither capacitive nor inductive components in the load or source. Of course this can mean such components have been balanced artificially.
Why DAM capacity in MW and generator in MVA?
Easy, you don't sell MVAh, you sell MWh. MVA is used in rating generators because it combines Watts and vars. MW is used to let you know what kind of money you can make, since you also are probably wanting to produce vars in order to support your grid.
How much power in a 15000 kva transformer?
The power in a 15 MVA (15000 KVA) transformer depends on the power factor. You did not specify the power factor, so I will assume a power factor of 0.92. Simply multiply MVA by PF and you get 13.8 MW.
What is the difference between Mw and mwh?
A megawatt ('MW', not 'Mw') is used to measure power, which is the rate at which you use energy.A megawatt hour ('MW.h', not 'mwh') is used to measure energy, and is defined as 'the amount of energy consumed, per hour, at a rate of one megawatt'.
