Active power is the power actually consumed and measured in kW or MW. Reactive power flows back and forth in a circuit and is measured in kVAR or MVAR. Apparent power is the product of voltage and current and is measured in kVA or MVA. These three powers are related and their relationship can be depicted in a power triangle diagram, with active power on the real axis, reactive power on the imaginary axis, and apparent power as the length of the complex power vector. Power factor is the ratio of active power to apparent power and indicates how effectively power is being used in a circuit.
2. Active, Reactive, & Apparent Power
• The power which is actually consumed or
utilized in an AC Circuit is called True
power or Active Power or real power.
• It is measured in kilo watt (kW) or MW.
• It is the actual outcomes of the electrical
system which runs the electric circuits or
load. 2
3. Active, Reactive, & Apparent
Power
• The power which flows back and forth that
mean it moves in both the direction in the
circuit or react upon itself, is called
Reactive Power.
• The reactive power is measured in kilo volt
ampere reactive (kVAR) or MVAR.
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4. Active, Reactive, & Apparent
Power
• The product of root mean square (RMS)
value of voltage and current is known as
Apparent Power.
• This power is measured in kVA or MVA.
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5. Active, reactive, and apparent
power
• It is taken into account when designing
and operating power systems.
• Conductors, transformers and generators
must be sized to carry the total current, not
just the current that does useful work.
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6. Active, reactive, and apparent
power
• Following terms are used to describe
energy flow in a system
• Active power P, or real power watt W
• Reactive power Q volt-ampere reactive
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7. Active, reactive, and apparent
power
• Complex power S volt-ampere (VA)
• Apparent power S the magnitude of
complex power S volt-ampere (VA)
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8. Active, reactive, and apparent
power
• These are all denoted in diagram called a
Power Triangle.
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9. Active, reactive, and apparent
power
• P is the active power
• Q is the reactive power (in this case
positive)
• S is the complex power and the length of
S is the apparent power.
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10. Active, reactive, and apparent
power
• Reactive power does not do any work, so
it is represented as the imaginary axis of
the vector diagram.
• Active power does do work, so it is the real
axis.
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11. Active, reactive, and apparent
power
• The unit for all forms of power is the watt
(symbol: W), but this unit is generally
reserved for active power.
• Apparent power is conventionally
expressed in volt-amperes (VA) since it is
the product of rms voltage and rms
current.
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12. Active, reactive, and apparent
power
• Since reactive power transfers no net
energy to the load, it is sometimes called
"wattless" power.
• The unit for reactive power is expressed
as var, which stands for
volt-ampere reactive
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13. Active, reactive, and apparent
power
• The mathematical relationship can be
represented by vectors or expressed using
complex numbers
• S = P + j Q (where j is the imaginary unit).
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14. Active, reactive, and apparent
power
• The formula for complex power (units: VA)
in phasor form is
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15. POWER FACTOR
• Power factor (PF or cosφ) is
the ratio between the power that can be
used in electric circuit (real power, P) and
the power from the result
of multiplication between
the current and voltage circuit (apparent
power, S).
• The power factor is defined as: P/S
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16. • PF ranges from 0 to 1.
• The higher the PF, the more efficient the
circuit is because more power can be
used, and vice versa.
• Factors that can cause PF to be less than
one is non-linear load, which
are capacitive load and inductive load.
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POWER FACTOR
17. POWER FACTOR
• Power factor is a measure of how
effectively you are using electricity.
• Various types of power are at work to
provide us with electrical energy.
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18. POWER FACTOR
• Improving PF can maximize current-
carrying capacity, improve voltage to
equipment, reduce power losses, and
lower electric bills.
• Simplest way to improve power factor is to
add PF correction capacitors to the
electrical system.
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19. POWER FACTOR
• PF correction capacitors act as reactive
current generators.
• They help offset the non-working power
used by inductive loads, thereby improving
the power factor.
• The interaction between PF capacitors
and specialized equipment, such as
variable speed drives, requires a well
designed system.
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