Voltage imbalances are one of the most common Power Quality problems in three-phase electrical networks. Being often overlooked, they can cause serious damage to electrical and electronic equipment.
Voltage unbalance can occur at any point of the three-phase electrical distribution system when a phase is excessively charged thus assuming a lower voltage value than the other phases.
In a three-phase system, the maximum voltage variation between the phases should be less than 2%, otherwise, significant damage may occur to electronic and electrical equipment, especially to three-phase transformers and motors.
ASYMMETRICAL VOLTAGE VARIATIONS
Asymmetry, otherwise called voltage imbalance, is a problem affecting three-phase networks, it can cause serious damage to equipment, but is often overlooked.
Often it happens that in a three-phase electrical system the users, which should be distributed in the same way on each phase, are charged on the phases in a different way thus generating voltage imbalances.
Equipment such as transformers and three-phase motors powered by a three-phase system with asymmetries, and therefore with voltage imbalances, could be subject to the following problems:
- Abnormal noise
- Excessive vibrations
- Early failures
For example, a 2.3% voltage imbalance on a 400 V motor results in a current imbalance of almost 18%, causing a temperature rise of 30°C.
To solve this specific recurring Power Quality problem in three-phase networks, IREM offers a wide range of voltage stabilizers, specially designed, to detect and compensate voltage imbalances automatically and independently on each phase.
The result is a rebalanced network, without asymmetries, which allows users to work in the nominal power supply conditions.
Thanks to the use of an IREM Y series stabilizer, the three-phase electrical and electronic equipment, sensitive to voltage imbalances, in addition to benefiting from better efficiency and longer life, will be preserved from the occurrence of any faults related to phase asymmetries.
THREE-PHASE NETWORK AFFECTED BY VOLTAGE IMBALANCES
THREE-PHASE NETWORK REBALANCED BY IREM STABILIZER
IREM SOLUTION TO VOLTAGE IMBALANCES:
MINISTAB and STEROSTAB Y SERIES
Ministab and Sterostab are registered names of two series of voltage stabilizers that offer a reliable and tested economic solution to inconveniences caused by voltage fluctuations. The use of voltage stabilizers increases the level of power quality and represents a real investment because the elimination of the inconveniences means a reduction in costs and an increase in productivity. Very
often it is only necessary to avoid a few minutes machine downtime or just one failure to repay the cost of the voltage stabilizers.
MINISTAB and STEROSTAB Y SERIES are three-phase voltage stabilisers with independent regulation of each phase.
Suitable for any type of load, they deliver a “true RMS” stabilised output voltage, even when strong harmonic distortions are present on the line.