Power dissipated by a load is referred to as true power. True power is symbolized by the letter P and is measured in the unit of Watts (W). The formula for Real power is I²*R or V²/R.
Questions tagged [real-power]
22 questions
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Do circuit breakers trip on Apparent or True Power?
The thermal and magnetic protection for AC circuit breakers take into account both the timing and the magnitude of the AC current passing through.
Does a standard circuit breaker trip on the current related to the Apparent (kVA) Power, or the…
Brethlosze
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Is reactive power periodic in nature? What is the exact difference between active power, average power, and real power?
Consider an RC circuit which is supplied by a sine source
$$v(t)=V_m\cdot \sin(\omega t)$$
The current through the circuit will be
$$i(t)=I_m\cdot \sin(\omega t+\phi) \\
\phi=\arctan \left(\dfrac{1}{\omega RC} \right)$$
The instantaneous power…
Sangeerth Prabakar
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What is the significance of UPS output power factor?
A UPS's output rating is shown as 2000VA/1800W. I understand that the power factor here is 0.9, but the device or load I will connect to the UPS might have pf<0.9 or pf=1 (for light bulb.) From my understanding, the real and reactive power will vary…
Md. Toufik Zaman
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Using Reactive vs Real Power to Manage Distribution System Voltages
This is my first post. The introduction of photovoltaics (PV) on the electrical distribution system creates changes to real power, resulting in voltage fluctuations. Those voltage fluctuations can be mitigated in two ways:
a) real power
b)…
user116801
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What is Real Power (AC circuit)?
I've beenstudying Real(True), Active and Apparent power in AC circuit.
I have understood all the concepts including phasor diagram, lagged sinusoidal waveform,the relationship between those three power.
However, I'm stuck on a this one concept at…
TM1
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What is the power factor of a classical power supply?
What is the power factor of a classical power supply ? I mean a transformer, rectifier and filter capacitor. Is it constant ?
Marus Gradinaru
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Is there a mathematical proof that reactive power regulates voltage?
So after studying the power triangle and trying to conceptualize real power and reactive power, I seem to have come across a contradiction, at least in my own head. Most explanations disregard reactive power as "useless" power or power that we don't…
RiFF RAFF
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What does mean if there is P+ and Q-?
If in a circuit there is real power positive and reactive power negative, what does mean in terms of power flow?
I undestand that the real power is produced in the generator/source and goes to the charge and the reactive goes backwards from the…
avelardo
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Angle difference of source/load for real power flow
simulate this circuit – Schematic created using CircuitLab
Suppose Vs = |Vs| (angle 0) and Vload = |Vload|exp(jθ).
'Because Vs has an angle of 0, θ must be negative in order for real power (P) to flow'
Why is the above statement true? Does real…
Alema416
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What are the exact meanings of reactive and apparent powers? Do we say they are supplied or consumed?
(The following doubt is from the topic of Sinusoidal Steady-State Analysis of electrical circuits)
I understand the meaning of real power - it is the average power consumed (or delivered) by an element in a circuit. But I do not get what reactive…
Aditya
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Complex power, real power
Given:
\$U_q = 220 V, f = 50 Hz, R_i=10 \Omega, R_a=40 \Omega, L_a=95.5 mH\$
I'm asked to determine the real power transformed in \$Z_a\$. Here I break down the formulas that I use:
\$Z_{total}=Z_{La}+Z_{Ra}+Z_{Ri}\$
\$I={U_q\over Z_{total}}\$
\$P…
hello
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calculating the average power using the oscilloscope
I am trying to measure the real power of an inductor, and in the manual it is said that I have to connect a resistor with low resistance to the inductor and then see the voltage difference between the current and voltage.
Question: Why do I need a…
Jack
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What is the real and apparent power of these steel cutters?
The US market model of this steel cutter is 120 VAC, 13.0 Amp.
The NZ market model is 230 VAC, 1,100 W.
I am trying to wrap my head around whether 1,100 W is the real power and so whether the apparent power is 120×13 = 1,560 VA. That comes to the…
Greendrake
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Short circuit analysis
Im given the next distribution line with a generator and a load
The generator is set at \$23\,kV\$ the line impedance is \$9.5\Omega +j19.055\Omega\$ and the aparent power is \$1.5MW+j2MVars\$ in the load and the load voltage is the \$20.44\,kV\$…
avelardo
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Where am I wrong about my calculation of power loss?
The power loss of circuit is \$16kW\$ when the power factor, PF, is 0.6 lag. Now if I improve the PF from \$0.6\$ lag to \$0.8\$ lag, what is the power loss now?
The solution provide me the formula below
\$P_{L2}=P_{L1}\times…
Shine Sun
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