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Invisible
and costly pollution
Today's electronic loads share a common element: the electrical power supply. This is giving rise to the growing concern of harmonic pollution. Industrial, commercial and domestic networks are all affected by this pollution - and the problem is growing.
The main linear loads causing this distortion are computers, servers, high frequency lighting, monitors, fax machines, copiers, VDU's etc. Virtually all equipment that contains electronics adds to the growing concern of harmonic pollution.
Harmonic current is a natural by-product of the manner in which non-linear (electronic) loads draw current. Non-linear loads by definition draw current for only a small portion of the electrical cycle.
THE RESULT
OF THIS NON-LINEAR CURRENT IS HARMONICS
Harmonic Distortion
Non-linear loads produce harmonic currents. As they flow across the impedance of the distribution network, they generate voltage distortion. The problems that arise can be broken down into those associated with high current distortion THD(I) and high voltage distortion THD(V):
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Overheating of conductors and insulation degradation. |
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Neutral overload* |
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Increased transformer losses (need to over-size). |
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Nuisance tripping of circuit breakers. |
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Neutral-earth potential* |
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Significant voltage distortion on networks with generators. |
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Overheating and possible resonance with capacitors. |
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Lighting ballast failures. |
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PC monitor stroboscopic effect* |
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Maloperation of microprocessor-based equipment* |
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Re-injection of harmonic currents into the utility network. |
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Effects of high voltage distortion: |
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Cause linear devices to draw non-linear current (see effects above). |
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Torque pulsation in motors. |
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Capacitor dielectric failure. |
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Insulation breakdown. |
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PC monitor and power supply failure. |
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Electric lighting failure. |
* Caused by triple-n (neutral currents) harmonics flowing across network impedance.
THE SOLUTION:
Harmonics Conditioning
We can supply the solution to your problem (or problem about to happen) by adding a Harmonics Conditioner which will provide the simplest and most effective method to eradicate the wide spectrum of harmonic currents produced by today's electronic loads, including those harmonic generated phase to neutral.
With this method only a very simple analysis is required. Any number of filters can be applied and they can be placed anywhere within the network to cancel harmonics at the source. Dependent upon the reason for filtering, the unit can be installed as a global filter at the main service entrance, or on the feeders to specific non-linear loads.
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Benefits: |
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Simplest solution for removing multiple harmonics. |
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Negates
the need for 200% rated neutrals, oversized transformers, cables, etc. -reduces infrastructure costs. |
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No need for extensive surveying or network modelling. |
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Allows standard generator sizing as with non-linear loads. |
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Will not resonate with upstream transformers. |
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Filters without the generation of reactive power for applications with near-unity power factor. |
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Will not increase fault levels. |
As you add more electronic equipment to your organisation the probability of Harmonic Pollution effecting the efficiency increases.
Why not call us, to arrange for an engineer to survey your installation?