THE ISSUE
The electricity produced in power plants is circulated through the electricity transmission and distribution networks and it is supplied/delivered to consumers; the quality of electricity (known as «Power Quality») is one of the important factors that determine the economic efficiency of both consumers and electrical networks.
Electrical devices are designed to work in distributing systems defined by set nominal values in terms of voltage and frequency (for example, 400V at 50Hz).
In actual fact, electric energy distribution might not ensure the stability of said nominal parameters. Voltage in particular can vary even considerably in relation to the nominal value. These variation can cause undesired and potentially dangerous conditions for the users. Voltage “fluctuations’ can be ‘fast’ and wa ste themselves away in a few milliseconds (for example, distribution lines hit by lightning) or ‘slow’, with duration that can last several seconds, minutes or even hours depending on the cause.
Slow fluctuations can be generated by increased voltage level (‘surge’ due to poor MV regulation at distribution level, disconnection of large loads, overvoltage at generators output, etc) or – more frequently – by decreased voltage level (‘sags’ due to connection of large loads, motor startup, undersized distribution lines, faults to ground, poor MV voltage regulation, etc).
In case of voltage variation, the voltage stabiliser is the solution that guarantees for the best cost/benefit ratio.
THE SOLUTION
The voltage stabiliser has proven to be an effective solution able to prevent potentially dangerous situations created by input voltage instability.
- Typical situations where voltage can be subject to fluctuation beyond the admitted tolerance are:
- Loads supplied by weak or undersized distributing lines (rural areas or locations supplied by long distributing lines such as breeding farms, tourist resorts, hotels, etc).
- Users located near distributing station and therefore subject to voltage increase.
- Private premises with high power installations (swimming pool pumps, big chillers, special lighting systems, lifts) and/or particularly voltage sensitive loads (high power consumer electronics, etc.).
- Loads located near large industrial plants where individual high power devices (MV motors) can induce voltage reduction at startup.
- Island operating loads (ships, offshore rigs, loads not connected to the public grid).
In comparison to other types of equipment, the voltage stabilser offers a number of advantages that very often make it the optimum solution:
- Usually lower price.
- High output voltage stability guaranteed even for wide input fluctuation.
- Absence of introduced harmonic distortion.
- Robust and reliable construction, allowing for use in hard environments.
- Overload capability up to twice the rated current (max 2 mins).
- No concerns in terms of storage, transportation, maintenance and disposal due to the fact that batteries are not used.
- Smooth and reliable regulation of the load voltage ensuring a ±0.5% accuracy even with important input voltage variation.
- High efficiency.
- High inrush current withstand capability.
- Reduced dimension, simple to run, ‘plug&play’ operating mode.
