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ELECTRICAL LOSSES DUE TO SKIN EFFECT AND PROXIMITY EFFECT WHITE PAPER

Authored by: www.ep200.com

Heat in the System
Reducing heat in the electrical system is critical to improving power quality. Wire is the heart of the electrical distribution system. A typical facility can have tens of thousands of feet of wire throughout the facility and wire is a major source of heat. Heat prematurely degrades wire quality causing both energy losses and burnout of the wire.


The resistance in an electrical system is never constant. It depends on various factors such as humidity, length of wire and high frequency noise. Wire is the main conduit of electricity and is central to the electrical system. Resistance in the wire converts a portion of electrical energy into heat.

Heat in the wire decreases the efficiency of the distribution system. It also creates a fire hazard. Contraction and expansion of wire due to cooling and heating of wire loosens wire connections. This makes it possible for the electricity to arc and the heat output can reach 1800 degrees Fahrenheit. This is enough heat to ignite wood or insulation. Skin effect and proximity effect are the two major sources of heat in wire.

Skin Effect
Skin effect is the trend of current to flow on the circumference of the wire so that the current density is greater at the surface than at the core. High frequency noise in the range of 1kHz-1.5MHz increases the inductive reactance of the wire. This forces the electrical charge towards the outer surface of the wire. This means that the total available space of the wire is not used to carry the electrical power.

Proximity Effect
Along with skin effect, proximity effect is a common problem found in every electrical system. Proximity effect is defined as the jumping magnetic field from one conductor to another conductor nearby. The major causes of proximity effect are closeness of the wires, bends in the wire, skin effect and high frequency noise.

Skin Effect & Proximity Effect in Real World
Load imbalance is defined as the imbalance in the current distribution to the load. In a three phase electrical signal, the magnitude of the current in all three phases should be equal. Unequal distribution in the three phases results in decreased performance of the load.

Conclusion
Heat in the electrical distribution system is a major source of electrical losses in facilities. Wire is the heart of the distribution system and a major source of heat. High frequency noise in the range of 1kHz-1.5MHz is responsible for skin effect and proximity effect in wire. Skin effect and proximity effect are major contributors to heat losses and imbalance in current distribution. Environmental Potentials’ patented waveform correction technology is the safest and most efficient method of removing harmful noise from the system. EP waveform correctors are powerful low pass filters, which not only remove noise but also maintains the sinusoidal nature of the waveform. This significantly reduces heat and electrical losses.

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