enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Mathematics of three-phase electric power - Wikipedia

    en.wikipedia.org/wiki/Mathematics_of_three-phase...

    One voltage cycle of a three-phase system, labeled 0 to 360° (2π radians) along the time axis. The plotted line represents the variation of instantaneous voltage (or current) with respect to time. This cycle repeats with a frequency that depends on the power system.

  3. Crest factor - Wikipedia

    en.wikipedia.org/wiki/Crest_factor

    The peak-to-average power ratio (PAPR) is the peak amplitude squared (giving the peak power) divided by the RMS value squared (giving the average power). [1] It is the square of the crest factor. When expressed in decibels , crest factor and PAPR are equivalent, due to the way decibels are calculated for power ratios vs amplitude ratios .

  4. Power factor - Wikipedia

    en.wikipedia.org/wiki/Power_factor

    Because current in these systems is interrupted by a switching action, the current contains frequency components that are multiples of the power system frequency. Distortion power factor is a measure of how much the harmonic distortion of a load current decreases the average power transferred to the load. Sinusoidal voltage and non-sinusoidal ...

  5. Root mean square - Wikipedia

    en.wikipedia.org/wiki/Root_mean_square

    The same principle applies, and (for example) a current of 10 amps used for 12 hours each 24-hour day represents an average current of 5 amps, but an RMS current of 7.07 amps, in the long term. The term RMS power is sometimes erroneously used (e.g., in the audio industry) as a synonym for mean power or average power (it is proportional to the ...

  6. Power (physics) - Wikipedia

    en.wikipedia.org/wiki/Power_(physics)

    Power is the rate with respect to time at which work is done; it is the time derivative of work: =, where P is power, W is work, and t is time.. We will now show that the mechanical power generated by a force F on a body moving at the velocity v can be expressed as the product: = =

  7. Ripple (electrical) - Wikipedia

    en.wikipedia.org/wiki/Ripple_(electrical)

    Ripple itself is a composite (non-sinusoidal) waveform consisting of harmonics of some fundamental frequency which is usually the original AC line frequency, but in the case of switched-mode power supplies, the fundamental frequency can be tens of kilohertz to megahertz. The characteristics and components of ripple depend on its source: there ...

  8. Alternating current - Wikipedia

    en.wikipedia.org/wiki/Alternating_current

    A schematic representation of long distance electric power transmission. From left to right: G=generator, U=step-up transformer, V=voltage at beginning of transmission line, Pt=power entering transmission line, I=current in wires, R=total resistance in wires, Pw=power lost in transmission line, Pe=power reaching the end of the transmission line, D=step-down transformer, C=consumers.

  9. AC power - Wikipedia

    en.wikipedia.org/wiki/AC_power

    The unit for power is the watt (symbol: W). Apparent power is often expressed in volt-amperes (VA) since it is the product of RMS voltage and RMS current. The unit for reactive power is var, which stands for volt-ampere reactive. Since reactive power transfers no net energy to the load, it is sometimes called "wattless" power.