IREM

POWER PROTECTION AND ENERGY SAVING

There is no formal (or univocal, academic, etc.) definition of the term “Power Quality”, however it is customary to refer to “Power Quality” such as the suitability of electricity to power the user appliances.
“Power Quality” is intrinsically linked to the interaction between the electrical system power supply and loads; the term refers both to the voltage quality and the current quality.
Any deviation from the ideal power conditions manifested in voltage, current or frequency
deviations – which is the cause of failure or malfunction of a powered equipment – constitutes a problem of “Power Quality”. Poor Power Quality inevitably causes problems to motors, drive devices, lighting systems and computer networks.
Many users of process plants and equipment underestimate the effects of poor “Power Quality”, which in terms of downtime, lack of productivity, data loss and damages to the equipment can be truly remarkable.
A reduced “Power Quality” can also give rise to unexpected high electricity costs and cause the application of penalties due to power supply network pollution.
Users with internal power quality problems, responsible for the network “pollution”, end up damaging other users connected to the network node and adversely affect the ability of substations to meet the quality requirements of the power supply.
The interdependence between the different systems only increases the vulnerability of the equipment to Power Quality problems, every plant and every company also have strategic systems for their business and any Power Quality problem can determine their interruption of operation at any time.

A wide range of devices is available to improve the power quality and ensure the best protection to professional equipment highly sensitive to electrical disturbances. As a matter of fact, any equipment needs a correct powering to ensure its performance. When this condition is not complied with, there are failures, errors and premature ageing.
To protect sensitive equipment, it is possible to have recourse to several devices which, depending on their characteristics, complexity and cost, ensure different levels of efficacy. The choice should be made by assessing the degree of protection required, the entity of failures and the direct and indirect costs these may cause. It is therefore useful to know the most common electrical faults in order to adopt the most adequate protection and avoid ine¡ciency and failures.