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Active harmonics conditioners from 20 to 480 Amps
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Invisible, costly pollution
Nonlinear loads absorb currents.
All currents are made up of:
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the basic sinusoidal current (50 Hz, for example) called the fundamental (F),
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sinusoidal "polluting" currents which are multiples of F (2F, 3F, 4F, 5F, ... nF ) called harmonics.
These harmonics are increasingly polluting the voltages used by production facilities, pumping stations, data processing systems, telecommunication switchboards, TV studios, etc. and consume a significant proportion of available current.
This gives power users three types of problem: |
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Impact on the electrical installation with significant overheating in alternators, transformers, capacitors and cables ... The hidden costs of accelerated ageing in this type of equipment can be extremely high.
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Impact on utilisation of equipment with unexplained power outages and malfunctions in equipment sensitive to power quality. These failures cost money and reduce the effect of capital investment - with a negative effect on the bottom line!
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Impact on available electrical power as the current consumed by harmonics is totally lost and can cause up to 30% over-consumption. Utility bills soar even though there is less power available.
Existing standards
Three sets of standards designed to reduce the spread of harmonic pollution now apply.
These are:
Standards for equipment
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IEC 1000-3-2 or EN 61000-3-2 for low voltage appliances absorbing currents of under 16 A,
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IEC 1000-3-4 or EN 61000-3-4 for low voltage appliances or installations absorbing currents exceeding 16 A.
Standards for mains supply quality
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EN 50160 defines the voltages supplied by utility low voltage networks,
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EEEI 519 (Recommended Practices for Harmonics Control in Electrical Power Systems) is a joint recommendation by utility operators and subscribers to limit the impact of non-linear loads through a joint effort to reduce harmonics.
Compatibility standards between electrical networks and products
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IEC 1000-2-2 and recommendations by CIGRE (Conférence Internationale des Grands Réseaux Electriques) for public low voltage networks,
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IEC 1000-2-4 for industrial installations using low and medium voltage. Utilities actively encourage preventive actions to reduce electricity quality depreciations and overheating, and to increase the power factor.
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MGE Products