When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Electric power distribution - Wikipedia

    en.wikipedia.org/wiki/Electric_power_distribution

    Rural electrification systems tend to use higher distribution voltages because of the longer distances covered by distribution lines (see Rural Electrification Administration). 7.2, 12.47, 25, and 34.5 kV distribution is common in the United States; 11 kV and 33 kV are common in the UK, Australia and New Zealand; 11 kV and 22 kV are common in ...

  3. Telegrapher's equations - Wikipedia

    en.wikipedia.org/wiki/Telegrapher's_equations

    The equations and their solutions are applicable from 0 Hz (i.e. direct current) to frequencies at which the transmission line structure can support higher order non-TEM modes. [2]: 282–286 The equations can be expressed in both the time domain and the frequency domain. In the time domain the independent variables are distance and time.

  4. Transmission line - Wikipedia

    en.wikipedia.org/wiki/Transmission_line

    The telegrapher's equations (or just telegraph equations) are a pair of linear differential equations which describe the voltage and current on an electrical transmission line with distance and time. They were developed by Oliver Heaviside who created the transmission line model , and are based on Maxwell's equations .

  5. Mathematics of three-phase electric power - Wikipedia

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

    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. In electrical engineering, three-phase electric power systems have at least three conductors carrying alternating voltages that are offset in time by one-third of the period ...

  6. Distribution transformer - Wikipedia

    en.wikipedia.org/wiki/Distribution_transformer

    Primaries provide power at the standard distribution voltages used in the area; these range from as low as 2.3 kV to about 35 kV depending on local distribution practice and standards, often 11 kV (50 Hz systems) and 13.8 kV (60 Hz systems) are used, but many other voltages are standard.

  7. Retarded time - Wikipedia

    en.wikipedia.org/wiki/Retarded_time

    Position vectors r and r′ used in the calculation. Retarded time t r or t′ is calculated with a "speed-distance-time" calculation for EM fields.. If the EM field is radiated at position vector r′ (within the source charge distribution), and an observer at position r measures the EM field at time t, the time delay for the field to travel from the charge distribution to the observer is |r ...

  8. Overhead power line - Wikipedia

    en.wikipedia.org/wiki/Overhead_power_line

    An overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy along large distances. It consists of one or more conductors (commonly multiples of three) suspended by towers or poles.

  9. List of electromagnetism equations - Wikipedia

    en.wikipedia.org/wiki/List_of_electromagnetism...

    Continuous charge distribution. The volume charge density ρ is the amount of charge per unit volume (cube), surface charge density σ is amount per unit surface area (circle) with outward unit normal nĚ‚, d is the dipole moment between two point charges, the volume density of these is the polarization density P.