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AC power

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116:, then the voltage and current are 90 degrees out of phase. For two quarters of each cycle, the product of voltage and current is positive, but for the other two quarters, the product is negative, indicating that on average, exactly as much energy flows into the load as flows back out. There is no net energy flow over each half cycle. In this case, only reactive power flows: There is no net transfer of energy to the load; however, electrical power does flow along the wires and returns by flowing in reverse along the same wires. The current required for this reactive power flow dissipates energy in the line resistance, even if the ideal load device consumes no energy itself. Practical loads have resistance as well as inductance, or capacitance, so both active and reactive powers will flow to normal loads. 1323:
inductors and capacitors. Energy flows in one direction from the source to the load. In AC power, the voltage and current both vary approximately sinusoidally. When there is inductance or capacitance in the circuit, the voltage and current waveforms do not line up perfectly. The power flow has two components – one component flows from source to load and can perform work at the load; the other portion, known as "reactive power", is due to the delay between voltage and current, known as phase angle, and cannot do useful work at the load. It can be thought of as current that is arriving at the wrong time (too late or too early). To distinguish reactive power from active power, it is measured in units of "
1249:. It is zero when the current leads or lags the voltage by 90 degrees. When the voltage and current are 180 degrees out of phase, the power factor is negative one, and the load is feeding energy into the source (an example would be a home with solar cells on the roof that feed power into the power grid when the sun is shining). Power factors are usually stated as "leading" or "lagging" to show the sign of the phase angle of current with respect to voltage. Voltage is designated as the base to which current angle is compared, meaning that current is thought of as either "leading" or "lagging" voltage. Where the waveforms are purely sinusoidal, the power factor is the cosine of the phase angle ( 140:
mechanism for controlling the power factor in electric power transmission; capacitors (or inductors) are inserted in a circuit to partially compensate for reactive power 'consumed' ('generated') by the load. Purely capacitive circuits supply reactive power with the current waveform leading the voltage waveform by 90 degrees, while purely inductive circuits absorb reactive power with the current waveform lagging the voltage waveform by 90 degrees. The result of this is that capacitive and inductive circuit elements tend to cancel each other out.
442: 1662:" is an important source of reactive power in the above power balance equation, which is generated by the capacitative nature of the transmission network itself. By making decisive switching actions in the early morning before the demand increases, the system gain can be maximized early on, helping to secure the system for the whole day. To balance the equation some pre-fault reactive generator use will be required. Other sources of reactive power that will also be used include shunt capacitors, shunt reactors, 1245:. For two systems transmitting the same amount of active power, the system with the lower power factor will have higher circulating currents due to energy that returns to the source from energy storage in the load. These higher currents produce higher losses and reduce overall transmission efficiency. A lower power factor circuit will have a higher apparent power and higher losses for the same amount of active power. The power factor is 1.0 when the voltage and current are in 4566: 38: 5145: 4077: 1352:, or large coils of wire to store energy in the form of a magnetic field. When a voltage is initially placed across the coil, the inductor strongly resists this change in a current and magnetic field, which causes a time delay for the current to reach its maximum value. This causes the current to lag behind the voltage in phase. Inductors are said to "sink" reactive power, and thus to cause a lagging power factor. 144: 1336:
by the capacitor and not have to be transferred over the transmission lines. This practice saves energy because it reduces the amount of energy that is required to be produced by the utility to do the same amount of work. Additionally, it allows for more efficient transmission line designs using smaller conductors or fewer bundled conductors and optimizing the design of transmission towers.
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causes an opposing voltage to develop across the capacitor. This voltage increases until some maximum dictated by the capacitor structure. In an AC network, the voltage across a capacitor is constantly changing. The capacitor opposes this change, causing the current to lead the voltage in phase. Capacitors are said to "source" reactive power, and thus to cause a leading power factor.
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In general, engineers are interested in the active power averaged over a period of time, whether it is a low frequency line cycle or a high frequency power converter switching period. The simplest way to get that result is to take the integral of the instantaneous calculation over the desired period:
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is used to reduce apparent power flow to a load by reducing reactive power supplied from transmission lines and providing it locally. For example, to compensate an inductive load, a shunt capacitor is installed close to the load itself. This allows all reactive power needed by the load to be supplied
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values of voltage and current. Apparent power is taken into account when designing and operating power systems, because although the current associated with reactive power does no work at the load, it still must be supplied by the power source. Conductors, transformers and generators must be sized to
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are a bad thing. They will increase the RMS current (since there will be non-zero terms added) and therefore apparent power, but they will have no effect on the active power transferred. Hence, harmonic currents will reduce the power factor. Harmonic currents can be reduced by a filter placed at the
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While active power and reactive power are well defined in any system, the definition of apparent power for unbalanced polyphase systems is considered to be one of the most controversial topics in power engineering. Originally, apparent power arose merely as a figure of merit. Major delineations of
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can source or sink reactive power, and provide a measure of control to system operators over reactive power flow and thus voltage. Because these devices have opposite effects on the phase angle between voltage and current, they can be used to "cancel out" each other's effects. This usually takes the
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For instance, a power factor of 0.68 means that only 68 percent of the total current supplied (in magnitude) is actually doing work; the remaining current does no work at the load. Power Factor is very important in Power sector substations. Form the national grid the sub sectors are required to have
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is nonzero. Therefore, the only product terms that have a nonzero average are those where the frequency of voltage and current match. In other words, it is possible to calculate active (average) power by simply treating each frequency separately and adding up the answers. Furthermore, if voltage of
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The 1920 committee found no consensus and the topic continued to dominate discussions. In 1930, another committee formed and once again failed to resolve the question. The transcripts of their discussions are the lengthiest and most controversial ever published by the AIEE. Further resolution of
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In a direct current circuit, the power flowing to the load is proportional to the product of the current through the load and the potential drop across the load. The power that happens because of a capacitor or inductor is called reactive power. It happens because of the AC nature of elements like
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Conventionally, capacitors are treated as if they generate reactive power, and inductors are treated as if they consume it. If a capacitor and an inductor are placed in parallel, then the currents flowing through the capacitor and the inductor tend to cancel rather than add. This is the fundamental
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Since an RMS value can be calculated for any waveform, apparent power can be calculated from this. For active power it would at first appear that it would be necessary to calculate many product terms and average all of them. However, looking at one of these product terms in more detail produces a
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Stored energy in the magnetic or electric field of a load device, such as a motor or capacitor, causes an offset between the current and the voltage waveforms. A capacitor is a device that stores energy in the form of an electric field. As current is driven through the capacitor, charge build-up
107:, the two quantities reverse their polarity at the same time. Hence, the instantaneous power, given by the product of voltage and current, is always positive, such that the direction of energy flow does not reverse and always is toward the resistor. In this case, only active power is transferred. 1371:
Transmission connected generators are generally required to support reactive power flow. For example, on the United Kingdom transmission system, generators are required by the Grid Code Requirements to supply their rated power between the limits of 0.85 power factor lagging and 0.90 power factor
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Energy stored in capacitive or inductive elements of the network gives rise to reactive power flow. Reactive power flow strongly influences the voltage levels across the network. Voltage levels and reactive power flow must be carefully controlled to allow a power system to be operated within
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itself. This is done because otherwise using the product V I to define S would result in a quantity that depends on the reference angle chosen for V or I, but defining S as V I* results in a quantity that doesn't depend on the reference angle and allows to relate S to P and Q.
2039: 2816: 1653: 2156: 80:. The portion of instantaneous power that results in no net transfer of energy but instead oscillates between the source and load in each cycle due to stored energy is known as instantaneous reactive power, and its amplitude is the absolute value of 3414: 2133: 1896: 2828: 1042: 838: 1802: 3153: 4029:{\displaystyle {\begin{aligned}&A\cos(\omega _{1}t+k_{1})\cos(\omega _{2}t+k_{2})\\={}&{\frac {A}{2}}\cos \left+{\frac {A}{2}}\cos \left\\={}&{\frac {A}{2}}\cos \left+{\frac {A}{2}}\cos \left\end{aligned}}} 2590: 414:. Understanding the relationship among these three quantities lies at the heart of understanding power engineering. The mathematical relationship among them can be represented by vectors or expressed using 3510: 4206:
To distinguish between linear and nonlinear loads, we may say that linear time-invariant loads are characterized so that an application of a sinusoidal voltage results in a sinusoidal flow of current.
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of the waveform. In practical applications, this would be done in the digital domain, where the calculation becomes trivial when compared to the use of rms and phase to determine active power:
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leading at the designated terminals. The system operator will perform switching actions to maintain a secure and economical voltage profile while maintaining a reactive power balance equation:
132:). Another consequence is that adding the apparent power for two loads will not accurately give the total power unless they have the same phase difference between current and voltage (the same 41:
The blinking of non-incandescent city lights is shown in this motion-blurred long exposure. The AC nature of the mains power is revealed by the dashed appearance of the traces of moving lights.
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This definition is useful because it applies to all waveforms, whether they are sinusoidal or not. This is particularly useful in power electronics, where non-sinusoidal waveforms are common.
2692: 2367:{\displaystyle S={\sqrt {\left(|V_{\mathrm {a} }^{2}|+|V_{\mathrm {b} }^{2}|+|V_{\mathrm {c} }^{2}|\right)\left(|I_{\mathrm {a} }^{2}|+|I_{\mathrm {b} }^{2}|+|I_{\mathrm {c} }^{2}|\right)}}} 1378: 2418: 517: 1221: 347: 4061:
input of the device. Typically this will consist of either just a capacitor (relying on parasitic resistance and inductance in the supply) or a capacitor-inductor network. An active
1101: 897: 3217: 595: 3294: 1293: 2045: 1808: 4222: 3006:{\displaystyle {\begin{aligned}P&=0\\Q&=|S|=V_{\mathrm {RMS} }I_{\mathrm {RMS} }=I_{\mathrm {RMS} }^{2}|X|={\frac {V_{\mathrm {RMS} }^{2}}{|X|}}\end{aligned}}} 1267: 213: 1154: 2646: 2619: 2449: 568: 3279: 3250: 4282: 2680: 3064: 3036: 4360:
Emanuel, Alexander (July 1993). "On The Definition of Power Factor and Apparent Power in Unbalanced Polyphase Circuits with Sinusoidal Voltage and Currents".
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minimum amount of power factor. Otherwise there are many loss. Mainly the required vary around 0.90 to 0.96 or more. Better the power factor less the loss.
1699:. In 1920, a "Special Joint Committee of the AIEE and the National Electric Light Association" met to resolve the issue. They considered two definitions. 4247: 915: 711: 3421: 406:. Since reactive power transfers no net energy to the load, it is sometimes called "wattless" power. It does, however, serve an important function in 1705: 3076: 2457: 218:
Engineers use the following terms to describe energy flow in a system (and assign each of them a different unit to differentiate between them):
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For a perfect capacitor or inductor, there is no net power transfer; so all power is reactive. Therefore, for a perfect capacitor or inductor:
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IEEE Standard Definitions for the Measurement of Electric Power Quantities Under Sinusoidal, Nonsinusoidal, Balanced, or Unbalanced Conditions
1366: 125: 5090: 3430: 1269:) between the current and voltage sinusoidal waveforms. Equipment data sheets and nameplates will often abbreviate power factor as " 1695:
power distribution, it became clear that the definition of apparent power and the power factor could not be applied to unbalanced
4332: 2034:{\displaystyle S_{V}=|P_{\mathrm {a} }+P_{\mathrm {b} }+P_{\mathrm {c} }+j(Q_{\mathrm {a} }+Q_{\mathrm {b} }+Q_{\mathrm {c} })|} 72:, results in net transfer of energy in one direction is known as instantaneous active power, and its time average is known as 4199: 4174: 4149: 2150:
theory was proposed in 1993 by Alexander Emanuel for unbalanced linear load supplied with asymmetrical sinusoidal voltages:
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The complex power is the vector sum of active and reactive power. The apparent power is the magnitude of the complex power.
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circuit at the input would generally reduce the harmonic currents further and maintain the power factor closer to unity.
619: 4293: 2811:{\displaystyle P=S=V_{\mathrm {RMS} }I_{\mathrm {RMS} }=I_{\mathrm {RMS} }^{2}R={\frac {V_{\mathrm {RMS} }^{2}}{R}}\,\!} 1648:{\displaystyle \mathrm {Generator\ MVARs+System\ gain+Shunt\ capacitors=MVAR\ Demand+Reactive\ losses+Shunt\ reactors} } 5095: 4410: 1327:", or var. These units can simplify to watts but are left as var to denote that they represent no actual work output. 4715: 4269: 1348:
Induction machines are some of the most common types of loads in the electric power system today. These machines use
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A perfect resistor stores no energy; so current and voltage are in phase. Therefore, there is no reactive power and
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that is, the root of squared sums of line voltages multiplied by the root of squared sums of line currents.
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form of capacitor banks being used to counteract the lagging power factor caused by induction motors.
5100: 4589: 4550: 3409:{\displaystyle P_{\text{avg}}={\frac {1}{t_{2}-t_{1}}}\int _{t_{1}}^{t_{2}}v(t)\,i(t)\,\mathrm {d} t} 3165: 1684: 705:
Consequentially, with reference to the power triangle, real power (units in watts, W) is derived as:
573: 350: 5075: 4883: 4823: 4480: 2128:{\displaystyle \mathrm {pf} _{V}={P_{\mathrm {a} }+P_{\mathrm {b} }+P_{\mathrm {c} } \over S_{V}}} 1891:{\displaystyle \mathrm {pf} _{A}={P_{\mathrm {a} }+P_{\mathrm {b} }+P_{\mathrm {c} } \over S_{A}}} 5174: 5014: 5004: 4994: 4062: 2683: 1310:. The concept of power dissipation in AC circuit is explained and illustrated with the example. 1272: 4935: 4798: 4581: 4470: 2147: 1663: 1252: 198: 5070: 4838: 4833: 4813: 1324: 96: 30:
This article is about power in AC systems. For information on utility-supplied AC power, see
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the mains supply is assumed to be a single frequency (which it usually is), this shows that
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Instantaneous power in AC systems when the current lags behind the voltage by 50 degrees.
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is the apparent power. Reactive power does not do any work, so it is represented as the
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on an electrical grid and, under certain operating conditions, collapse the network (a
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may result in periodic reversals of the direction of energy flow. Its SI unit is the
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is defined as being positive for an inductor and negative for a capacitor, then the
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denotes current in phasor form, with the amplitude as RMS. Also by convention, the
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This method of calculating the average power gives the active power regardless of
1037:{\displaystyle Q=|S|\sin {\varphi }=|I|^{2}X={\frac {|V|^{2}}{|Z|^{2}}}\times {X}} 833:{\displaystyle P=|S|\cos {\varphi }=|I|^{2}R={\frac {|V|^{2}}{|Z|^{2}}}\times {R}} 5040: 4999: 4977: 4858: 4828: 4793: 4753: 4555: 4251: 4141: 1659: 407: 5065: 5055: 4853: 4465: 4110: 3067: 435: 415: 93: 68:
The portion of instantaneous power that, averaged over a complete cycle of the
1797:{\displaystyle S_{A}=|S_{\mathrm {a} }|+|S_{\mathrm {b} }|+|S_{\mathrm {c} }|} 1302:
and the phase angle between voltage and current is 45.6°. The power factor is
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IEEE 100 : the authoritative dictionary of IEEE standards terms.-7th ed.
4082: 3148:{\displaystyle Q=I_{\mathrm {RMS} }^{2}X={\frac {V_{\mathrm {RMS} }^{2}}{X}}} 1246: 5105: 5080: 4945: 4914: 4728: 4530: 4390: 4244:
Definition of Active Power in the International Electrotechnical Vocabulary
2585:{\displaystyle P^{+}=3|V^{+}||I^{+}|\cos {(\arg {(V^{+})}-\arg {(I^{+})})}} 1242: 1236: 133: 129: 380:
of the vector diagram. Active power does do work, so it is the real axis.
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In a simple alternating current (AC) circuit consisting of a source and a
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Combining, the complex power (units in volt-amps, VA) is back-derived as
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These are all denoted in the adjacent diagram (called a power triangle).
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is the time rate of flow of energy past a given point of the circuit. In
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Active, reactive, apparent, and complex power in sinusoidal steady-state
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The ratio of active power to apparent power in a circuit is called the
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Other forms of complex power (units in volt-amps, VA) are derived from
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carry the total current, not just the current that does useful work.
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Thomas, Roland E.; Rosa, Albert J.; Toussaint, Gregory J. (2016).
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Reactive power (units in volts-amps-reactive, var) is derived as:
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For a purely reactive load, reactive power can be simplified to:
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that is, the arithmetic sum of the phase apparent powers; and
455: 3505:{\displaystyle P_{\text{avg}}={\frac {1}{n}}\sum _{k=1}^{n}VI} 844:
For a purely resistive load, real power can be simplified to:
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These are simplified diagrammatically by the power triangle.
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that is, the magnitude of total three-phase complex power.
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and its lack has been cited as a significant factor in the
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I vector), current leading voltage (quadrant IV vector).
4158: 402:. The unit for reactive power is var, which stands for 527:
denotes voltage in phasor form, with the amplitude as
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Insufficient reactive power can depress voltage levels
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Calculations and equations in sinusoidal steady-state
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However, the time average of a function of the form
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are the time-varying voltage and current waveforms.
4164: 2621:denotes the positive sequence voltage phasor, and 1160:and the apparent power (units in volt-amps, VA) as 906:denotes resistance (units in ohms, Ω) of the load. 694:{\displaystyle S=|I|^{2}Z={\frac {|V|^{2}}{Z^{*}}}} 4028: 3504: 3408: 3273: 3244: 3211: 3147: 3058: 3030: 3005: 2810: 2674: 2640: 2613: 2584: 2443: 2412: 2366: 2127: 2033: 1890: 1796: 1647: 1287: 1261: 1215: 1148: 1095: 1036: 891: 832: 693: 589: 562: 511: 387:(symbol: W). Apparent power is often expressed in 341: 207: 2807: 1339: 5161: 4192:Power System Harmonics and Passive Filter Design 4355: 4353: 2143:this debate did not come until the late 1990s. 368:is the reactive power (in this case positive), 2648:denotes the positive sequence current phasor. 1681:Phenomena of Retardation in the Induction Coil 4411: 4283:"August 14, 2003 Outage – Sequence of Events" 3516: 2413:{\displaystyle \mathrm {pf} ={P^{+} \over S}} 1367:Voltage control and reactive power management 454:The formula for complex power (units: VA) in 103:at the same frequency. If the load is purely 4350: 4128: 4126: 512:{\displaystyle S=VI^{*}=|S|\angle \varphi } 4418: 4404: 4167:The Analysis and Design of Linear Circuits 3070:signs can be removed from S and X and get 1691:(1915). However, with the development of 53:circuits, energy storage elements such as 4219:"Importance of Reactive Power for System" 3397: 3384: 3196: 2806: 1360: 1216:{\displaystyle |S|={\sqrt {P^{2}+Q^{2}}}} 4425: 4123: 1331:acceptable limits. A technique known as 440: 342:{\displaystyle \varphi =\arg(V)-\arg(I)} 142: 36: 4183: 4169:(8 ed.). Wiley. pp. 812–813. 2651: 1670:Unbalanced sinusoidal polyphase systems 372:is the complex power and the length of 99:load, both the current and voltage are 14: 5162: 1096:{\displaystyle Q={\frac {|V|^{2}}{X}}} 892:{\displaystyle P={\frac {|V|^{2}}{R}}} 4399: 2686:). Therefore, for a perfect resistor 2451:denotes the positive sequence power: 119:Apparent power is the product of the 287:Phase of voltage relative to current 193:Phase of voltage relative to current 27:Power in alternating current systems 4362:IEEE Transactions on Power Delivery 4189: 3159:Instantaneous power is defined as: 1689:Theoretical Elements of Engineering 24: 5096:Renewable energy commercialization 3399: 3129: 3126: 3123: 3098: 3095: 3092: 2971: 2968: 2965: 2930: 2927: 2924: 2909: 2906: 2903: 2891: 2888: 2885: 2790: 2787: 2784: 2759: 2756: 2753: 2738: 2735: 2732: 2720: 2717: 2714: 2386: 2383: 2341: 2311: 2281: 2244: 2214: 2184: 2106: 2091: 2076: 2054: 2051: 2017: 2002: 1987: 1966: 1951: 1936: 1869: 1854: 1839: 1817: 1814: 1783: 1758: 1733: 1641: 1638: 1635: 1632: 1629: 1626: 1623: 1620: 1614: 1611: 1608: 1605: 1602: 1596: 1593: 1590: 1587: 1584: 1581: 1575: 1572: 1569: 1566: 1563: 1560: 1557: 1554: 1548: 1545: 1542: 1539: 1536: 1533: 1527: 1524: 1521: 1518: 1512: 1509: 1506: 1503: 1500: 1497: 1494: 1491: 1488: 1485: 1479: 1476: 1473: 1470: 1467: 1461: 1458: 1455: 1452: 1446: 1443: 1440: 1437: 1434: 1431: 1425: 1422: 1419: 1416: 1413: 1407: 1404: 1401: 1398: 1395: 1392: 1389: 1386: 1383: 503: 25: 5186: 4384: 4359: 4316: 1317: 5144: 5143: 4564: 4194:. Wiley, IEEE Press. p. 2. 4075: 1115:(units in ohms, Ω) of the load. 391:(VA) since it is the product of 4319:The Analysis of Linear Circuits 4225:from the original on 2015-05-12 3212:{\displaystyle p(t)=v(t)\,i(t)} 1230: 590:{\displaystyle {\overline {I}}} 4325: 4310: 4275: 4256: 4236: 4211: 3613: 3584: 3575: 3546: 3499: 3493: 3487: 3481: 3394: 3388: 3381: 3375: 3268: 3262: 3239: 3233: 3206: 3200: 3193: 3187: 3178: 3172: 3043:of the capacitor or inductor. 2992: 2984: 2950: 2942: 2872: 2864: 2578: 2574: 2561: 2547: 2534: 2524: 2513: 2498: 2493: 2478: 2353: 2331: 2323: 2301: 2293: 2271: 2256: 2234: 2226: 2204: 2196: 2174: 2027: 2023: 1978: 1926: 1790: 1773: 1765: 1748: 1740: 1723: 1675:the concept are attributed to 1666:and voltage control circuits. 1340:Capacitive vs. inductive loads 1306:. The apparent power is then: 1179: 1171: 1077: 1068: 1013: 1004: 991: 982: 962: 953: 934: 926: 873: 864: 809: 800: 787: 778: 758: 749: 730: 722: 668: 659: 639: 630: 499: 491: 336: 330: 318: 312: 13: 1: 5091:Renewable Energy Certificates 5051:Cost of electricity by source 4973:Arc-fault circuit interrupter 4849:High-voltage shore connection 4321:. pp. 398 (section 8.3). 4116: 1298:Example: The active power is 5106:Spark/Dark/Quark/Bark spread 4904:Transmission system operator 4864:Mains electricity by country 4441:Automatic generation control 4292:. 2003-09-12. Archived from 4142:10.1109/IEEESTD.2010.5439063 1308:700 W / cos(45.6°) = 1000 VA 582: 7: 5131:List of electricity sectors 5126:Electric energy consumption 4844:High-voltage direct current 4819:Electric power transmission 4809:Electric power distribution 4486:Energy return on investment 4096:Electric power transmission 4068: 349:. Current lagging voltage ( 10: 5191: 5046:Carbon offsets and credits 4764:Three-phase electric power 3517:Multiple frequency systems 2146:A new definition based on 1364: 1288:{\displaystyle \cos \phi } 1234: 543:is used, which is denoted 412:Northeast blackout of 2003 383:The unit for power is the 29: 5139: 5114: 5101:Renewable Energy Payments 5024: 4961: 4923: 4777: 4714: 4625: 4590:Fossil fuel power station 4580: 4573: 4562: 4433: 3522:very interesting result. 4884:Single-wire earth return 4824:Electrical busbar system 4481:Energy demand management 1262:{\displaystyle \varphi } 208:{\displaystyle \varphi } 45:In an electric circuit, 5015:Residual-current device 5005:Power system protection 4995:Generator interlock kit 4250:April 23, 2015, at the 4063:power factor correction 2684:passive sign convention 1664:static VAR compensators 4799:Distributed generation 4471:Electric power quality 4391:"AC Power Java Applet" 4333:"Load differentiation" 4051:is zero provided that 4030: 3506: 3477: 3410: 3275: 3246: 3213: 3149: 3060: 3032: 3007: 2812: 2676: 2642: 2615: 2586: 2445: 2414: 2368: 2148:symmetrical components 2129: 2035: 1892: 1798: 1649: 1361:Reactive power control 1289: 1263: 1217: 1150: 1149:{\displaystyle S=P+jQ} 1097: 1038: 893: 834: 695: 591: 564: 513: 446: 343: 215: 209: 110:If the load is purely 42: 5071:Fossil fuel phase-out 4839:Electricity retailing 4834:Electrical substation 4814:Electric power system 4031: 3507: 3457: 3411: 3276: 3247: 3214: 3150: 3061: 3033: 3008: 2813: 2677: 2643: 2641:{\displaystyle I^{+}} 2616: 2614:{\displaystyle V^{+}} 2587: 2446: 2444:{\displaystyle P^{+}} 2415: 2369: 2130: 2036: 1893: 1799: 1650: 1333:reactive compensation 1325:volt-amperes reactive 1290: 1264: 1218: 1151: 1098: 1039: 894: 835: 696: 592: 565: 563:{\displaystyle I^{*}} 514: 444: 364:is the active power, 344: 210: 146: 40: 4427:Electricity delivery 3529: 3431: 3295: 3274:{\displaystyle i(t)} 3256: 3245:{\displaystyle v(t)} 3227: 3166: 3077: 3050: 3022: 2829: 2693: 2660: 2652:Real number formulas 2625: 2598: 2458: 2428: 2379: 2157: 2046: 1909: 1809: 1706: 1379: 1354:Induction generators 1273: 1253: 1167: 1125: 1055: 916: 851: 712: 620: 613:(units in ohms, Ω). 574: 547: 465: 404:volt-ampere reactive 297: 249:volt-ampere reactive 199: 5036:Availability factor 4988:Sulfur hexafluoride 4869:Overhead power line 4769:Virtual power plant 4744:Induction generator 4697:Sustainable biofuel 4506:Home energy storage 4496:Grid energy storage 4461:Droop speed control 4190:Das, J. C. (2015). 4091:War of the currents 3371: 3139: 3108: 2981: 2940: 2800: 2769: 2675:{\displaystyle P=S} 2351: 2321: 2291: 2254: 2224: 2194: 1295:" for this reason. 283:: volt-ampere (VA); 51:alternating current 47:instantaneous power 4910:Transmission tower 4521:Nameplate capacity 4317:Close, Charles M. 4026: 4024: 3502: 3406: 3343: 3271: 3242: 3209: 3145: 3117: 3086: 3056: 3028: 3003: 3001: 2959: 2918: 2808: 2778: 2747: 2672: 2638: 2611: 2582: 2441: 2410: 2364: 2335: 2305: 2275: 2238: 2208: 2178: 2125: 2031: 1888: 1794: 1645: 1304:cos(45.6°) = 0.700 1285: 1259: 1213: 1146: 1093: 1034: 889: 830: 691: 587: 560: 509: 447: 339: 216: 205: 149:The Power Triangle 43: 5157: 5156: 5061:Environmental tax 4941:Cascading failure 4710: 4709: 4546:Utility frequency 4374:10.1109/61.252612 4221:. 21 March 2011. 4201:978-1-118-86162-2 4176:978-1-119-23538-5 4151:978-0-7381-6058-0 4106:Mains electricity 4058:harmonic currents 3942: 3851: 3739: 3635: 3455: 3441: 3341: 3305: 3143: 3059:{\displaystyle X} 3031:{\displaystyle X} 2997: 2804: 2408: 2362: 2123: 1886: 1697:polyphase systems 1619: 1580: 1532: 1484: 1451: 1412: 1211: 1091: 1024: 887: 820: 689: 585: 537:complex conjugate 279:of complex power 32:Mains electricity 16:(Redirected from 5182: 5147: 5146: 5056:Energy subsidies 5010:Protective relay 4951:Rolling blackout 4578: 4577: 4568: 4536:Power-flow study 4476:Electrical fault 4420: 4413: 4406: 4397: 4396: 4378: 4377: 4357: 4348: 4347: 4345: 4344: 4335:. Archived from 4329: 4323: 4322: 4314: 4308: 4307: 4305: 4304: 4298: 4287: 4279: 4273: 4260: 4254: 4240: 4234: 4233: 4231: 4230: 4215: 4209: 4208: 4187: 4181: 4180: 4162: 4156: 4155: 4130: 4085: 4080: 4079: 4050: 4035: 4033: 4032: 4027: 4025: 4021: 4017: 4016: 4015: 4003: 4002: 3987: 3983: 3982: 3981: 3969: 3968: 3943: 3935: 3930: 3926: 3925: 3924: 3912: 3911: 3896: 3892: 3891: 3890: 3878: 3877: 3852: 3844: 3840: 3831: 3827: 3826: 3822: 3821: 3820: 3805: 3804: 3787: 3783: 3782: 3781: 3766: 3765: 3740: 3732: 3727: 3723: 3722: 3718: 3717: 3716: 3701: 3700: 3683: 3679: 3678: 3677: 3662: 3661: 3636: 3628: 3624: 3612: 3611: 3596: 3595: 3574: 3573: 3558: 3557: 3535: 3511: 3509: 3508: 3503: 3476: 3471: 3456: 3448: 3443: 3442: 3439: 3422:harmonic content 3415: 3413: 3412: 3407: 3402: 3370: 3369: 3368: 3358: 3357: 3356: 3342: 3340: 3339: 3338: 3326: 3325: 3312: 3307: 3306: 3303: 3280: 3278: 3277: 3272: 3251: 3249: 3248: 3243: 3218: 3216: 3215: 3210: 3154: 3152: 3151: 3146: 3144: 3138: 3133: 3132: 3116: 3107: 3102: 3101: 3065: 3063: 3062: 3057: 3037: 3035: 3034: 3029: 3012: 3010: 3009: 3004: 3002: 2998: 2996: 2995: 2987: 2980: 2975: 2974: 2958: 2953: 2945: 2939: 2934: 2933: 2914: 2913: 2912: 2896: 2895: 2894: 2875: 2867: 2817: 2815: 2814: 2809: 2805: 2799: 2794: 2793: 2777: 2768: 2763: 2762: 2743: 2742: 2741: 2725: 2724: 2723: 2681: 2679: 2678: 2673: 2647: 2645: 2644: 2639: 2637: 2636: 2620: 2618: 2617: 2612: 2610: 2609: 2591: 2589: 2588: 2583: 2581: 2577: 2573: 2572: 2550: 2546: 2545: 2516: 2511: 2510: 2501: 2496: 2491: 2490: 2481: 2470: 2469: 2450: 2448: 2447: 2442: 2440: 2439: 2419: 2417: 2416: 2411: 2409: 2404: 2403: 2394: 2389: 2373: 2371: 2370: 2365: 2363: 2361: 2357: 2356: 2350: 2345: 2344: 2334: 2326: 2320: 2315: 2314: 2304: 2296: 2290: 2285: 2284: 2274: 2264: 2260: 2259: 2253: 2248: 2247: 2237: 2229: 2223: 2218: 2217: 2207: 2199: 2193: 2188: 2187: 2177: 2167: 2134: 2132: 2131: 2126: 2124: 2122: 2121: 2112: 2111: 2110: 2109: 2096: 2095: 2094: 2081: 2080: 2079: 2068: 2063: 2062: 2057: 2040: 2038: 2037: 2032: 2030: 2022: 2021: 2020: 2007: 2006: 2005: 1992: 1991: 1990: 1971: 1970: 1969: 1956: 1955: 1954: 1941: 1940: 1939: 1929: 1921: 1920: 1897: 1895: 1894: 1889: 1887: 1885: 1884: 1875: 1874: 1873: 1872: 1859: 1858: 1857: 1844: 1843: 1842: 1831: 1826: 1825: 1820: 1803: 1801: 1800: 1795: 1793: 1788: 1787: 1786: 1776: 1768: 1763: 1762: 1761: 1751: 1743: 1738: 1737: 1736: 1726: 1718: 1717: 1654: 1652: 1651: 1646: 1644: 1617: 1578: 1530: 1482: 1449: 1410: 1309: 1305: 1301: 1294: 1292: 1291: 1286: 1268: 1266: 1265: 1260: 1222: 1220: 1219: 1214: 1212: 1210: 1209: 1197: 1196: 1187: 1182: 1174: 1155: 1153: 1152: 1147: 1102: 1100: 1099: 1094: 1092: 1087: 1086: 1085: 1080: 1071: 1065: 1043: 1041: 1040: 1035: 1033: 1025: 1023: 1022: 1021: 1016: 1007: 1001: 1000: 999: 994: 985: 979: 971: 970: 965: 956: 948: 937: 929: 898: 896: 895: 890: 888: 883: 882: 881: 876: 867: 861: 839: 837: 836: 831: 829: 821: 819: 818: 817: 812: 803: 797: 796: 795: 790: 781: 775: 767: 766: 761: 752: 744: 733: 725: 700: 698: 697: 692: 690: 688: 687: 678: 677: 676: 671: 662: 656: 648: 647: 642: 633: 596: 594: 593: 588: 586: 578: 569: 567: 566: 561: 559: 558: 518: 516: 515: 510: 502: 494: 486: 485: 408:electrical grids 360:In the diagram, 348: 346: 345: 340: 214: 212: 211: 206: 21: 5190: 5189: 5185: 5184: 5183: 5181: 5180: 5179: 5160: 5159: 5158: 5153: 5135: 5119: 5117: 5110: 5041:Capacity factor 5029: 5027: 5020: 5000:Numerical relay 4978:Circuit breaker 4966: 4964: 4957: 4919: 4859:Load management 4829:Electrical grid 4794:Demand response 4787: 4782: 4773: 4754:Microgeneration 4706: 4621: 4569: 4560: 4556:Vehicle-to-grid 4429: 4424: 4387: 4382: 4381: 4358: 4351: 4342: 4340: 4331: 4330: 4326: 4315: 4311: 4302: 4300: 4296: 4285: 4281: 4280: 4276: 4261: 4257: 4252:Wayback Machine 4241: 4237: 4228: 4226: 4217: 4216: 4212: 4202: 4188: 4184: 4177: 4163: 4159: 4152: 4132: 4131: 4124: 4119: 4081: 4074: 4071: 4040: 4023: 4022: 4011: 4007: 3998: 3994: 3977: 3973: 3964: 3960: 3959: 3955: 3954: 3950: 3934: 3920: 3916: 3907: 3903: 3886: 3882: 3873: 3869: 3868: 3864: 3863: 3859: 3843: 3841: 3839: 3833: 3832: 3816: 3812: 3800: 3796: 3795: 3791: 3777: 3773: 3761: 3757: 3756: 3752: 3751: 3747: 3731: 3712: 3708: 3696: 3692: 3691: 3687: 3673: 3669: 3657: 3653: 3652: 3648: 3647: 3643: 3627: 3625: 3623: 3617: 3616: 3607: 3603: 3591: 3587: 3569: 3565: 3553: 3549: 3532: 3530: 3527: 3526: 3519: 3472: 3461: 3447: 3438: 3434: 3432: 3429: 3428: 3398: 3364: 3360: 3359: 3352: 3348: 3347: 3334: 3330: 3321: 3317: 3316: 3311: 3302: 3298: 3296: 3293: 3292: 3257: 3254: 3253: 3228: 3225: 3224: 3167: 3164: 3163: 3134: 3122: 3121: 3115: 3103: 3091: 3090: 3078: 3075: 3074: 3051: 3048: 3047: 3023: 3020: 3019: 3000: 2999: 2991: 2983: 2982: 2976: 2964: 2963: 2957: 2949: 2941: 2935: 2923: 2922: 2902: 2901: 2897: 2884: 2883: 2879: 2871: 2863: 2856: 2850: 2849: 2839: 2832: 2830: 2827: 2826: 2795: 2783: 2782: 2776: 2764: 2752: 2751: 2731: 2730: 2726: 2713: 2712: 2708: 2694: 2691: 2690: 2661: 2658: 2657: 2654: 2632: 2628: 2626: 2623: 2622: 2605: 2601: 2599: 2596: 2595: 2568: 2564: 2560: 2541: 2537: 2533: 2523: 2512: 2506: 2502: 2497: 2492: 2486: 2482: 2477: 2465: 2461: 2459: 2456: 2455: 2435: 2431: 2429: 2426: 2425: 2399: 2395: 2393: 2382: 2380: 2377: 2376: 2352: 2346: 2340: 2339: 2330: 2322: 2316: 2310: 2309: 2300: 2292: 2286: 2280: 2279: 2270: 2269: 2265: 2255: 2249: 2243: 2242: 2233: 2225: 2219: 2213: 2212: 2203: 2195: 2189: 2183: 2182: 2173: 2172: 2168: 2166: 2158: 2155: 2154: 2117: 2113: 2105: 2104: 2100: 2090: 2089: 2085: 2075: 2074: 2070: 2069: 2067: 2058: 2050: 2049: 2047: 2044: 2043: 2026: 2016: 2015: 2011: 2001: 2000: 1996: 1986: 1985: 1981: 1965: 1964: 1960: 1950: 1949: 1945: 1935: 1934: 1930: 1925: 1916: 1912: 1910: 1907: 1906: 1880: 1876: 1868: 1867: 1863: 1853: 1852: 1848: 1838: 1837: 1833: 1832: 1830: 1821: 1813: 1812: 1810: 1807: 1806: 1789: 1782: 1781: 1777: 1772: 1764: 1757: 1756: 1752: 1747: 1739: 1732: 1731: 1727: 1722: 1713: 1709: 1707: 1704: 1703: 1672: 1382: 1380: 1377: 1376: 1369: 1363: 1342: 1320: 1307: 1303: 1299: 1274: 1271: 1270: 1254: 1251: 1250: 1239: 1233: 1205: 1201: 1192: 1188: 1186: 1178: 1170: 1168: 1165: 1164: 1126: 1123: 1122: 1081: 1076: 1075: 1067: 1066: 1064: 1056: 1053: 1052: 1029: 1017: 1012: 1011: 1003: 1002: 995: 990: 989: 981: 980: 978: 966: 961: 960: 952: 944: 933: 925: 917: 914: 913: 877: 872: 871: 863: 862: 860: 852: 849: 848: 825: 813: 808: 807: 799: 798: 791: 786: 785: 777: 776: 774: 762: 757: 756: 748: 740: 729: 721: 713: 710: 709: 683: 679: 672: 667: 666: 658: 657: 655: 643: 638: 637: 629: 621: 618: 617: 597:), rather than 577: 575: 572: 571: 554: 550: 548: 545: 544: 498: 490: 481: 477: 466: 463: 462: 452: 416:complex numbers 298: 295: 294: 200: 197: 196: 190: 181: 172: 163: 154: 152: 90: 35: 28: 23: 22: 15: 12: 11: 5: 5188: 5178: 5177: 5175:Electric power 5172: 5155: 5154: 5152: 5151: 5140: 5137: 5136: 5134: 5133: 5128: 5122: 5120: 5116:Statistics and 5115: 5112: 5111: 5109: 5108: 5103: 5098: 5093: 5088: 5083: 5078: 5073: 5068: 5066:Feed-in tariff 5063: 5058: 5053: 5048: 5043: 5038: 5032: 5030: 5025: 5022: 5021: 5019: 5018: 5012: 5007: 5002: 4997: 4992: 4991: 4990: 4985: 4975: 4969: 4967: 4962: 4959: 4958: 4956: 4955: 4954: 4953: 4943: 4938: 4933: 4927: 4925: 4921: 4920: 4918: 4917: 4912: 4907: 4901: 4896: 4891: 4886: 4881: 4876: 4871: 4866: 4861: 4856: 4854:Interconnector 4851: 4846: 4841: 4836: 4831: 4826: 4821: 4816: 4811: 4806: 4804:Dynamic demand 4801: 4796: 4790: 4788: 4778: 4775: 4774: 4772: 4771: 4766: 4761: 4756: 4751: 4746: 4741: 4736: 4734:Combined cycle 4731: 4726: 4720: 4718: 4712: 4711: 4708: 4707: 4705: 4704: 4699: 4694: 4689: 4688: 4687: 4682: 4677: 4672: 4667: 4657: 4652: 4647: 4642: 4637: 4631: 4629: 4623: 4622: 4620: 4619: 4614: 4613: 4612: 4607: 4602: 4597: 4586: 4584: 4575: 4571: 4570: 4563: 4561: 4559: 4558: 4553: 4548: 4543: 4538: 4533: 4528: 4523: 4518: 4513: 4511:Load-following 4508: 4503: 4498: 4493: 4488: 4483: 4478: 4473: 4468: 4466:Electric power 4463: 4458: 4453: 4448: 4443: 4437: 4435: 4431: 4430: 4423: 4422: 4415: 4408: 4400: 4394: 4393: 4386: 4385:External links 4383: 4380: 4379: 4368:(3): 841–852. 4349: 4324: 4309: 4274: 4255: 4235: 4210: 4200: 4182: 4175: 4157: 4150: 4136:. IEEE. 2010. 4121: 4120: 4118: 4115: 4114: 4113: 4111:Deformed power 4108: 4103: 4098: 4093: 4087: 4086: 4070: 4067: 4037: 4036: 4020: 4014: 4010: 4006: 4001: 3997: 3993: 3990: 3986: 3980: 3976: 3972: 3967: 3963: 3958: 3953: 3949: 3946: 3941: 3938: 3933: 3929: 3923: 3919: 3915: 3910: 3906: 3902: 3899: 3895: 3889: 3885: 3881: 3876: 3872: 3867: 3862: 3858: 3855: 3850: 3847: 3842: 3838: 3835: 3834: 3830: 3825: 3819: 3815: 3811: 3808: 3803: 3799: 3794: 3790: 3786: 3780: 3776: 3772: 3769: 3764: 3760: 3755: 3750: 3746: 3743: 3738: 3735: 3730: 3726: 3721: 3715: 3711: 3707: 3704: 3699: 3695: 3690: 3686: 3682: 3676: 3672: 3668: 3665: 3660: 3656: 3651: 3646: 3642: 3639: 3634: 3631: 3626: 3622: 3619: 3618: 3615: 3610: 3606: 3602: 3599: 3594: 3590: 3586: 3583: 3580: 3577: 3572: 3568: 3564: 3561: 3556: 3552: 3548: 3545: 3542: 3539: 3536: 3534: 3518: 3515: 3514: 3513: 3501: 3498: 3495: 3492: 3489: 3486: 3483: 3480: 3475: 3470: 3467: 3464: 3460: 3454: 3451: 3446: 3437: 3418: 3417: 3405: 3401: 3396: 3393: 3390: 3387: 3383: 3380: 3377: 3374: 3367: 3363: 3355: 3351: 3346: 3337: 3333: 3329: 3324: 3320: 3315: 3310: 3301: 3270: 3267: 3264: 3261: 3241: 3238: 3235: 3232: 3221: 3220: 3208: 3205: 3202: 3199: 3195: 3192: 3189: 3186: 3183: 3180: 3177: 3174: 3171: 3157: 3156: 3142: 3137: 3131: 3128: 3125: 3120: 3114: 3111: 3106: 3100: 3097: 3094: 3089: 3085: 3082: 3055: 3027: 3015: 3014: 2994: 2990: 2986: 2979: 2973: 2970: 2967: 2962: 2956: 2952: 2948: 2944: 2938: 2932: 2929: 2926: 2921: 2917: 2911: 2908: 2905: 2900: 2893: 2890: 2887: 2882: 2878: 2874: 2870: 2866: 2862: 2859: 2857: 2855: 2852: 2851: 2848: 2845: 2842: 2840: 2838: 2835: 2834: 2820: 2819: 2803: 2798: 2792: 2789: 2786: 2781: 2775: 2772: 2767: 2761: 2758: 2755: 2750: 2746: 2740: 2737: 2734: 2729: 2722: 2719: 2716: 2711: 2707: 2704: 2701: 2698: 2671: 2668: 2665: 2653: 2650: 2635: 2631: 2608: 2604: 2593: 2592: 2580: 2576: 2571: 2567: 2563: 2559: 2556: 2553: 2549: 2544: 2540: 2536: 2532: 2529: 2526: 2522: 2519: 2515: 2509: 2505: 2500: 2495: 2489: 2485: 2480: 2476: 2473: 2468: 2464: 2438: 2434: 2422: 2421: 2407: 2402: 2398: 2392: 2388: 2385: 2374: 2360: 2355: 2349: 2343: 2338: 2333: 2329: 2325: 2319: 2313: 2308: 2303: 2299: 2295: 2289: 2283: 2278: 2273: 2268: 2263: 2258: 2252: 2246: 2241: 2236: 2232: 2228: 2222: 2216: 2211: 2206: 2202: 2198: 2192: 2186: 2181: 2176: 2171: 2165: 2162: 2137: 2136: 2120: 2116: 2108: 2103: 2099: 2093: 2088: 2084: 2078: 2073: 2066: 2061: 2056: 2053: 2041: 2029: 2025: 2019: 2014: 2010: 2004: 1999: 1995: 1989: 1984: 1980: 1977: 1974: 1968: 1963: 1959: 1953: 1948: 1944: 1938: 1933: 1928: 1924: 1919: 1915: 1900: 1899: 1883: 1879: 1871: 1866: 1862: 1856: 1851: 1847: 1841: 1836: 1829: 1824: 1819: 1816: 1804: 1792: 1785: 1780: 1775: 1771: 1767: 1760: 1755: 1750: 1746: 1742: 1735: 1730: 1725: 1721: 1716: 1712: 1671: 1668: 1656: 1655: 1643: 1640: 1637: 1634: 1631: 1628: 1625: 1622: 1616: 1613: 1610: 1607: 1604: 1601: 1598: 1595: 1592: 1589: 1586: 1583: 1577: 1574: 1571: 1568: 1565: 1562: 1559: 1556: 1553: 1550: 1547: 1544: 1541: 1538: 1535: 1529: 1526: 1523: 1520: 1517: 1514: 1511: 1508: 1505: 1502: 1499: 1496: 1493: 1490: 1487: 1481: 1478: 1475: 1472: 1469: 1466: 1463: 1460: 1457: 1454: 1448: 1445: 1442: 1439: 1436: 1433: 1430: 1427: 1424: 1421: 1418: 1415: 1409: 1406: 1403: 1400: 1397: 1394: 1391: 1388: 1385: 1365:Main article: 1362: 1359: 1341: 1338: 1319: 1318:Reactive power 1316: 1284: 1281: 1278: 1258: 1235:Main article: 1232: 1229: 1225: 1224: 1208: 1204: 1200: 1195: 1191: 1185: 1181: 1177: 1173: 1158: 1157: 1145: 1142: 1139: 1136: 1133: 1130: 1105: 1104: 1090: 1084: 1079: 1074: 1070: 1063: 1060: 1046: 1045: 1032: 1028: 1020: 1015: 1010: 1006: 998: 993: 988: 984: 977: 974: 969: 964: 959: 955: 951: 947: 943: 940: 936: 932: 928: 924: 921: 901: 900: 886: 880: 875: 870: 866: 859: 856: 842: 841: 828: 824: 816: 811: 806: 802: 794: 789: 784: 780: 773: 770: 765: 760: 755: 751: 747: 743: 739: 736: 732: 728: 724: 720: 717: 703: 702: 686: 682: 675: 670: 665: 661: 654: 651: 646: 641: 636: 632: 628: 625: 584: 581: 557: 553: 521: 520: 508: 505: 501: 497: 493: 489: 484: 480: 476: 473: 470: 451: 448: 436:imaginary unit 378:imaginary axis 355: 354: 338: 335: 332: 329: 326: 323: 320: 317: 314: 311: 308: 305: 302: 284: 269:Apparent power 266: 252: 241:Reactive power 238: 204: 184:Apparent power 166:Reactive power 97:time-invariant 89: 86: 82:reactive power 26: 9: 6: 4: 3: 2: 5187: 5176: 5173: 5171: 5168: 5167: 5165: 5150: 5142: 5141: 5138: 5132: 5129: 5127: 5124: 5123: 5121: 5113: 5107: 5104: 5102: 5099: 5097: 5094: 5092: 5089: 5087: 5086:Pigouvian tax 5084: 5082: 5079: 5077: 5074: 5072: 5069: 5067: 5064: 5062: 5059: 5057: 5054: 5052: 5049: 5047: 5044: 5042: 5039: 5037: 5034: 5033: 5031: 5023: 5016: 5013: 5011: 5008: 5006: 5003: 5001: 4998: 4996: 4993: 4989: 4986: 4984: 4983:Earth-leakage 4981: 4980: 4979: 4976: 4974: 4971: 4970: 4968: 4960: 4952: 4949: 4948: 4947: 4944: 4942: 4939: 4937: 4934: 4932: 4929: 4928: 4926: 4924:Failure modes 4922: 4916: 4913: 4911: 4908: 4905: 4902: 4900: 4897: 4895: 4892: 4890: 4887: 4885: 4882: 4880: 4877: 4875: 4874:Power station 4872: 4870: 4867: 4865: 4862: 4860: 4857: 4855: 4852: 4850: 4847: 4845: 4842: 4840: 4837: 4835: 4832: 4830: 4827: 4825: 4822: 4820: 4817: 4815: 4812: 4810: 4807: 4805: 4802: 4800: 4797: 4795: 4792: 4791: 4789: 4786: 4781: 4776: 4770: 4767: 4765: 4762: 4760: 4759:Rankine cycle 4757: 4755: 4752: 4750: 4747: 4745: 4742: 4740: 4739:Cooling tower 4737: 4735: 4732: 4730: 4727: 4725: 4722: 4721: 4719: 4717: 4713: 4703: 4700: 4698: 4695: 4693: 4690: 4686: 4683: 4681: 4678: 4676: 4673: 4671: 4668: 4666: 4663: 4662: 4661: 4658: 4656: 4653: 4651: 4648: 4646: 4643: 4641: 4638: 4636: 4633: 4632: 4630: 4628: 4624: 4618: 4615: 4611: 4608: 4606: 4603: 4601: 4598: 4596: 4593: 4592: 4591: 4588: 4587: 4585: 4583: 4582:Non-renewable 4579: 4576: 4572: 4567: 4557: 4554: 4552: 4549: 4547: 4544: 4542: 4539: 4537: 4534: 4532: 4529: 4527: 4524: 4522: 4519: 4517: 4514: 4512: 4509: 4507: 4504: 4502: 4501:Grid strength 4499: 4497: 4494: 4492: 4489: 4487: 4484: 4482: 4479: 4477: 4474: 4472: 4469: 4467: 4464: 4462: 4459: 4457: 4456:Demand factor 4454: 4452: 4449: 4447: 4444: 4442: 4439: 4438: 4436: 4432: 4428: 4421: 4416: 4414: 4409: 4407: 4402: 4401: 4398: 4392: 4389: 4388: 4375: 4371: 4367: 4363: 4356: 4354: 4339:on 2015-10-25 4338: 4334: 4328: 4320: 4313: 4299:on 2007-10-20 4295: 4291: 4284: 4278: 4271: 4270:0-7381-2601-2 4267: 4264: 4259: 4253: 4249: 4246: 4245: 4239: 4224: 4220: 4214: 4207: 4203: 4197: 4193: 4186: 4178: 4172: 4168: 4161: 4153: 4147: 4143: 4139: 4135: 4129: 4127: 4122: 4112: 4109: 4107: 4104: 4102: 4099: 4097: 4094: 4092: 4089: 4088: 4084: 4083:Energy portal 4078: 4073: 4066: 4064: 4059: 4054: 4048: 4044: 4018: 4012: 4008: 4004: 3999: 3995: 3991: 3988: 3984: 3978: 3974: 3970: 3965: 3961: 3956: 3951: 3947: 3944: 3939: 3936: 3931: 3927: 3921: 3917: 3913: 3908: 3904: 3900: 3897: 3893: 3887: 3883: 3879: 3874: 3870: 3865: 3860: 3856: 3853: 3848: 3845: 3836: 3828: 3823: 3817: 3813: 3809: 3806: 3801: 3797: 3792: 3788: 3784: 3778: 3774: 3770: 3767: 3762: 3758: 3753: 3748: 3744: 3741: 3736: 3733: 3728: 3724: 3719: 3713: 3709: 3705: 3702: 3697: 3693: 3688: 3684: 3680: 3674: 3670: 3666: 3663: 3658: 3654: 3649: 3644: 3640: 3637: 3632: 3629: 3620: 3608: 3604: 3600: 3597: 3592: 3588: 3581: 3578: 3570: 3566: 3562: 3559: 3554: 3550: 3543: 3540: 3537: 3525: 3524: 3523: 3496: 3490: 3484: 3478: 3473: 3468: 3465: 3462: 3458: 3452: 3449: 3444: 3435: 3427: 3426: 3425: 3423: 3403: 3391: 3385: 3378: 3372: 3365: 3361: 3353: 3349: 3344: 3335: 3331: 3327: 3322: 3318: 3313: 3308: 3299: 3291: 3290: 3289: 3285: 3282: 3265: 3259: 3236: 3230: 3203: 3197: 3190: 3184: 3181: 3175: 3169: 3162: 3161: 3160: 3140: 3135: 3118: 3112: 3109: 3104: 3087: 3083: 3080: 3073: 3072: 3071: 3069: 3053: 3044: 3042: 3038: 3025: 2988: 2977: 2960: 2954: 2946: 2936: 2919: 2915: 2898: 2880: 2876: 2868: 2860: 2858: 2853: 2846: 2843: 2841: 2836: 2825: 2824: 2823: 2801: 2796: 2779: 2773: 2770: 2765: 2748: 2744: 2727: 2709: 2705: 2702: 2699: 2696: 2689: 2688: 2687: 2685: 2669: 2666: 2663: 2649: 2633: 2629: 2606: 2602: 2569: 2565: 2557: 2554: 2551: 2542: 2538: 2530: 2527: 2520: 2517: 2507: 2503: 2487: 2483: 2474: 2471: 2466: 2462: 2454: 2453: 2452: 2436: 2432: 2405: 2400: 2396: 2390: 2375: 2358: 2347: 2336: 2327: 2317: 2306: 2297: 2287: 2276: 2266: 2261: 2250: 2239: 2230: 2220: 2209: 2200: 2190: 2179: 2169: 2163: 2160: 2153: 2152: 2151: 2149: 2144: 2140: 2118: 2114: 2101: 2097: 2086: 2082: 2071: 2064: 2059: 2042: 2012: 2008: 1997: 1993: 1982: 1975: 1972: 1961: 1957: 1946: 1942: 1931: 1922: 1917: 1913: 1905: 1904: 1903: 1881: 1877: 1864: 1860: 1849: 1845: 1834: 1827: 1822: 1805: 1778: 1769: 1753: 1744: 1728: 1719: 1714: 1710: 1702: 1701: 1700: 1698: 1694: 1690: 1686: 1682: 1678: 1667: 1665: 1661: 1599: 1551: 1515: 1464: 1428: 1375: 1374: 1373: 1368: 1358: 1355: 1351: 1346: 1337: 1334: 1328: 1326: 1315: 1311: 1296: 1282: 1279: 1276: 1256: 1248: 1244: 1238: 1228: 1206: 1202: 1198: 1193: 1189: 1183: 1175: 1163: 1162: 1161: 1143: 1140: 1137: 1134: 1131: 1128: 1121: 1120: 1119: 1116: 1114: 1110: 1088: 1082: 1072: 1061: 1058: 1051: 1050: 1049: 1030: 1026: 1018: 1008: 996: 986: 975: 972: 967: 957: 949: 945: 941: 938: 930: 922: 919: 912: 911: 910: 907: 905: 884: 878: 868: 857: 854: 847: 846: 845: 826: 822: 814: 804: 792: 782: 771: 768: 763: 753: 745: 741: 737: 734: 726: 718: 715: 708: 707: 706: 684: 680: 673: 663: 652: 649: 644: 634: 626: 623: 616: 615: 614: 612: 608: 603: 600: 579: 555: 551: 542: 538: 534: 530: 526: 506: 495: 487: 482: 478: 474: 471: 468: 461: 460: 459: 457: 443: 439: 437: 433: 429: 426: +  425: 422: =  421: 417: 413: 409: 405: 401: 397: 394: 390: 386: 381: 379: 375: 371: 367: 363: 358: 352: 333: 327: 324: 321: 315: 309: 306: 303: 300: 292: 288: 285: 282: 278: 274: 270: 267: 264: 260: 256: 255:Complex power 253: 250: 246: 242: 239: 236: 232: 228: 224: 221: 220: 219: 202: 194: 189: 188:|S| 185: 180: 176: 175:Complex power 171: 167: 162: 158: 151: 150: 145: 141: 137: 135: 131: 127: 122: 117: 115: 114: 108: 106: 102: 98: 95: 85: 83: 79: 75: 71: 66: 64: 60: 56: 52: 48: 39: 33: 19: 5081:Net metering 5028:and policies 4946:Power outage 4915:Utility pole 4879:Pumped hydro 4785:distribution 4780:Transmission 4729:Cogeneration 4723: 4531:Power factor 4365: 4361: 4341:. Retrieved 4337:the original 4327: 4318: 4312: 4301:. Retrieved 4294:the original 4277: 4262: 4258: 4242: 4238: 4227:. Retrieved 4213: 4205: 4191: 4185: 4166: 4160: 4133: 4052: 4046: 4042: 4038: 3520: 3419: 3286: 3283: 3222: 3158: 3045: 3018: 3016: 2821: 2655: 2594: 2423: 2145: 2141: 2138: 1901: 1688: 1680: 1673: 1657: 1370: 1347: 1343: 1329: 1321: 1312: 1297: 1243:power factor 1240: 1237:Power factor 1231:Power factor 1226: 1159: 1117: 1108: 1106: 1047: 908: 903: 902: 843: 704: 606: 604: 598: 540: 532: 524: 522: 453: 431: 427: 423: 419: 389:volt-amperes 382: 377: 373: 369: 365: 361: 359: 356: 290: 286: 280: 272: 268: 258: 254: 244: 240: 230: 226: 223:Active power 222: 217: 192: 191:   187: 183: 182:   178: 174: 173:   169: 165: 164:   160: 157:Active power 156: 155:   148: 147: 138: 134:power factor 118: 112: 109: 91: 81: 77: 74:active power 73: 67: 44: 5076:Load factor 4931:Black start 4899:Transformer 4600:Natural gas 4551:Variability 4526:Peak demand 4516:Merit order 4446:Backfeeding 4101:Transformer 2682:(using the 1693:three phase 1683:(1888) and 1660:system gain 609:, the load 263:volt-ampere 70:AC waveform 5164:Categories 5118:production 4963:Protective 4894:Super grid 4889:Smart grid 4716:Generation 4650:Geothermal 4541:Repowering 4343:2015-04-29 4303:2008-02-18 4229:2015-04-29 4117:References 231:real power 101:sinusoidal 78:real power 59:capacitors 18:Real power 5026:Economics 4749:Micro CHP 4627:Renewable 4610:Petroleum 4605:Oil shale 4491:Grid code 4451:Base load 4272:, page 23 4005:− 3975:ω 3971:− 3962:ω 3948:⁡ 3884:ω 3871:ω 3857:⁡ 3798:ω 3789:− 3759:ω 3745:⁡ 3694:ω 3655:ω 3641:⁡ 3589:ω 3582:⁡ 3551:ω 3544:⁡ 3459:∑ 3345:∫ 3328:− 3041:reactance 2558:⁡ 2552:− 2531:⁡ 2521:⁡ 1685:Steinmetz 1350:inductors 1283:ϕ 1280:⁡ 1257:φ 1113:reactance 1027:× 946:φ 942:⁡ 823:× 742:φ 738:⁡ 685:∗ 611:impedance 583:¯ 556:∗ 507:φ 504:∠ 483:∗ 458:form is: 328:⁡ 322:− 310:⁡ 301:φ 277:magnitude 203:φ 105:resistive 55:inductors 5170:AC power 5149:Category 4936:Brownout 4724:AC power 4434:Concepts 4248:Archived 4223:Archived 4069:See also 1111:denotes 428:j Q 398:and RMS 351:quadrant 130:blackout 113:reactive 4965:devices 4675:Thermal 4670:Osmotic 4665:Current 4645:Biomass 4635:Biofuel 4617:Nuclear 4574:Sources 3068:modulus 3039:is the 1677:Stanley 434:is the 430:(where 400:current 396:voltage 275:|: the 4660:Marine 4640:Biogas 4268:  4198:  4173:  4148:  3223:where 3017:where 1618:  1579:  1531:  1483:  1450:  1411:  1107:where 531:, and 523:where 456:phasor 251:(var); 94:linear 5017:(GFI) 4906:(TSO) 4692:Solar 4680:Tidal 4655:Hydro 4297:(PDF) 4286:(PDF) 1658:The " 1300:700 W 1247:phase 265:(VA); 229:, or 4783:and 4702:Wind 4685:Wave 4595:Coal 4290:FERC 4266:ISBN 4196:ISBN 4171:ISBN 4146:ISBN 4041:cos( 3252:and 570:(or 385:watt 237:(W); 235:watt 63:watt 57:and 4370:doi 4138:doi 3945:cos 3854:cos 3742:cos 3638:cos 3579:cos 3541:cos 3440:avg 3304:avg 3046:If 2555:arg 2528:arg 2518:cos 1687:'s 1679:'s 1277:cos 939:sin 735:cos 539:of 529:RMS 438:). 393:RMS 325:arg 307:arg 271:, | 136:). 121:RMS 76:or 5166:: 4364:. 4352:^ 4288:. 4204:. 4144:. 4125:^ 4045:+ 4043:ωt 418:, 289:, 261:: 257:, 247:: 243:, 233:: 225:, 195:, 186:, 177:, 168:, 159:, 84:. 65:. 4419:e 4412:t 4405:v 4376:. 4372:: 4366:8 4346:. 4306:. 4232:. 4179:. 4154:. 4140:: 4053:ω 4049:) 4047:k 4019:] 4013:2 4009:k 4000:1 3996:k 3992:+ 3989:t 3985:) 3979:2 3966:1 3957:( 3952:[ 3940:2 3937:A 3932:+ 3928:] 3922:2 3918:k 3914:+ 3909:1 3905:k 3901:+ 3898:t 3894:) 3888:2 3880:+ 3875:1 3866:( 3861:[ 3849:2 3846:A 3837:= 3829:] 3824:) 3818:2 3814:k 3810:+ 3807:t 3802:2 3793:( 3785:) 3779:1 3775:k 3771:+ 3768:t 3763:1 3754:( 3749:[ 3737:2 3734:A 3729:+ 3725:] 3720:) 3714:2 3710:k 3706:+ 3703:t 3698:2 3689:( 3685:+ 3681:) 3675:1 3671:k 3667:+ 3664:t 3659:1 3650:( 3645:[ 3633:2 3630:A 3621:= 3614:) 3609:2 3605:k 3601:+ 3598:t 3593:2 3585:( 3576:) 3571:1 3567:k 3563:+ 3560:t 3555:1 3547:( 3538:A 3512:. 3500:] 3497:k 3494:[ 3491:I 3488:] 3485:k 3482:[ 3479:V 3474:n 3469:1 3466:= 3463:k 3453:n 3450:1 3445:= 3436:P 3416:. 3404:t 3400:d 3395:) 3392:t 3389:( 3386:i 3382:) 3379:t 3376:( 3373:v 3366:2 3362:t 3354:1 3350:t 3336:1 3332:t 3323:2 3319:t 3314:1 3309:= 3300:P 3269:) 3266:t 3263:( 3260:i 3240:) 3237:t 3234:( 3231:v 3219:, 3207:) 3204:t 3201:( 3198:i 3194:) 3191:t 3188:( 3185:v 3182:= 3179:) 3176:t 3173:( 3170:p 3155:. 3141:X 3136:2 3130:S 3127:M 3124:R 3119:V 3113:= 3110:X 3105:2 3099:S 3096:M 3093:R 3088:I 3084:= 3081:Q 3054:X 3026:X 3013:. 2993:| 2989:X 2985:| 2978:2 2972:S 2969:M 2966:R 2961:V 2955:= 2951:| 2947:X 2943:| 2937:2 2931:S 2928:M 2925:R 2920:I 2916:= 2910:S 2907:M 2904:R 2899:I 2892:S 2889:M 2886:R 2881:V 2877:= 2873:| 2869:S 2865:| 2861:= 2854:Q 2847:0 2844:= 2837:P 2818:. 2802:R 2797:2 2791:S 2788:M 2785:R 2780:V 2774:= 2771:R 2766:2 2760:S 2757:M 2754:R 2749:I 2745:= 2739:S 2736:M 2733:R 2728:I 2721:S 2718:M 2715:R 2710:V 2706:= 2703:S 2700:= 2697:P 2670:S 2667:= 2664:P 2634:+ 2630:I 2607:+ 2603:V 2579:) 2575:) 2570:+ 2566:I 2562:( 2548:) 2543:+ 2539:V 2535:( 2525:( 2514:| 2508:+ 2504:I 2499:| 2494:| 2488:+ 2484:V 2479:| 2475:3 2472:= 2467:+ 2463:P 2437:+ 2433:P 2420:, 2406:S 2401:+ 2397:P 2391:= 2387:f 2384:p 2359:) 2354:| 2348:2 2342:c 2337:I 2332:| 2328:+ 2324:| 2318:2 2312:b 2307:I 2302:| 2298:+ 2294:| 2288:2 2282:a 2277:I 2272:| 2267:( 2262:) 2257:| 2251:2 2245:c 2240:V 2235:| 2231:+ 2227:| 2221:2 2215:b 2210:V 2205:| 2201:+ 2197:| 2191:2 2185:a 2180:V 2175:| 2170:( 2164:= 2161:S 2135:, 2119:V 2115:S 2107:c 2102:P 2098:+ 2092:b 2087:P 2083:+ 2077:a 2072:P 2065:= 2060:V 2055:f 2052:p 2028:| 2024:) 2018:c 2013:Q 2009:+ 2003:b 1998:Q 1994:+ 1988:a 1983:Q 1979:( 1976:j 1973:+ 1967:c 1962:P 1958:+ 1952:b 1947:P 1943:+ 1937:a 1932:P 1927:| 1923:= 1918:V 1914:S 1898:, 1882:A 1878:S 1870:c 1865:P 1861:+ 1855:b 1850:P 1846:+ 1840:a 1835:P 1828:= 1823:A 1818:f 1815:p 1791:| 1784:c 1779:S 1774:| 1770:+ 1766:| 1759:b 1754:S 1749:| 1745:+ 1741:| 1734:a 1729:S 1724:| 1720:= 1715:A 1711:S 1642:s 1639:r 1636:o 1633:t 1630:c 1627:a 1624:e 1621:r 1615:t 1612:n 1609:u 1606:h 1603:S 1600:+ 1597:s 1594:e 1591:s 1588:s 1585:o 1582:l 1576:e 1573:v 1570:i 1567:t 1564:c 1561:a 1558:e 1555:R 1552:+ 1549:d 1546:n 1543:a 1540:m 1537:e 1534:D 1528:R 1525:A 1522:V 1519:M 1516:= 1513:s 1510:r 1507:o 1504:t 1501:i 1498:c 1495:a 1492:p 1489:a 1486:c 1480:t 1477:n 1474:u 1471:h 1468:S 1465:+ 1462:n 1459:i 1456:a 1453:g 1447:m 1444:e 1441:t 1438:s 1435:y 1432:S 1429:+ 1426:s 1423:R 1420:A 1417:V 1414:M 1408:r 1405:o 1402:t 1399:a 1396:r 1393:e 1390:n 1387:e 1384:G 1223:. 1207:2 1203:Q 1199:+ 1194:2 1190:P 1184:= 1180:| 1176:S 1172:| 1156:, 1144:Q 1141:j 1138:+ 1135:P 1132:= 1129:S 1109:X 1103:, 1089:X 1083:2 1078:| 1073:V 1069:| 1062:= 1059:Q 1044:. 1031:X 1019:2 1014:| 1009:Z 1005:| 997:2 992:| 987:V 983:| 976:= 973:X 968:2 963:| 958:I 954:| 950:= 935:| 931:S 927:| 923:= 920:Q 904:R 899:. 885:R 879:2 874:| 869:V 865:| 858:= 855:P 840:. 827:R 815:2 810:| 805:Z 801:| 793:2 788:| 783:V 779:| 772:= 769:R 764:2 759:| 754:I 750:| 746:= 731:| 727:S 723:| 719:= 716:P 701:. 681:Z 674:2 669:| 664:V 660:| 653:= 650:Z 645:2 640:| 635:I 631:| 627:= 624:S 607:Z 599:I 580:I 552:I 541:I 533:I 525:V 519:, 500:| 496:S 492:| 488:= 479:I 475:V 472:= 469:S 432:j 424:P 420:S 374:S 370:S 366:Q 362:P 337:) 334:I 331:( 319:) 316:V 313:( 304:= 291:φ 281:S 273:S 259:S 245:Q 227:P 179:S 170:Q 161:P 34:. 20:)

Index

Real power
Mains electricity

instantaneous power
alternating current
inductors
capacitors
watt
AC waveform
linear
time-invariant
sinusoidal
resistive
reactive
RMS
Insufficient reactive power can depress voltage levels
blackout
power factor

watt
volt-ampere reactive
volt-ampere
magnitude
quadrant
watt
volt-amperes
RMS
voltage
current
volt-ampere reactive

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