The voltage stabiliser is made essentially of buck-boost transformer, voltage regulator and electronic control. By means of the digitally controlled system, the stabiliser is able to compensate for a widely fluctuating incoming voltage stabilising it within a ±0.5% accuracy range in relation to the rated value. Based on a microprocessor sampling the output voltage at high frequency, the control system operates the voltage regulator motors in order to guarantee the voltage stability.
The voltage regulator is an autotransformer with variable transformer ratio, effectively performing the voltage adjustment. Depending on the rated power of the stabiliser, the regulator can be columnar or toroidal. The stabilisation takes place on the ‘rms’ value of the voltage and is not affected by harmonic distortion in the mains. The stabiliser can operate with a load variation range from 0 to 100% with a regulation speed depending on the input voltage percentage variation and on the design (indicatively, it can vary between 8 and 30msec/V).
The voltage stabiliser is not affected by the load power factor and since regulation is performed without chopping the voltage sine wave, neither an appreciable harmonic distortion nor a phase displacement is introduced on the downstream line. The equipment is housed in an IP21 metal enclosure with RAL7035 finish. The standard stabilisers are air cooled (naturally or with aided ventilation over a certain temperature).
ORION stabilisers can be chosen to match different ranges of input voltage fluctuation (±15/±20%; ±25/±30%; +15/-25%; +15/-35%;+15/-45%).
Standard models offer a double input connection so that with the same unit two different input variations (±15/±20% or ±25/±30%) can be dealt with.
The regulation in the ORION Y stabilisers is independent on each phase. These stabilisers are used with three-phase loads and single-phase loads with 100% unbalance with unbalance input rated voltage and are suitable even in case of non-symmetric mains. In this configuration, the voltage stabiliser requires the neutral wire presence. It can also operate without neutral wire by adding a device able to generate it (D/Yn isolating transformer or neutral inductance).
Every stabiliser belonging to this range is equipped with the same control board used on VEGA and ANTARES models, thus simplifying maintenance operations and spare parts storage.
Up to 45kVA, the stabilisers are equipped with wheels for easy handling. Automatic circuit breakers are provided on the regulation circuit to protect against overload and short circuit on the voltage regulator. The auxiliary circuit is protected by fuses.
The measuring instrumentation for the ORION Y stabilisers is installed on the cabinet door and consists of one multi-task digital network analyser. Such instrument is able to provide with information regarding the status of the line downstream the voltage stabiliser, such as phase and linked voltages, current, power factor, active power, apparent power, reactive power, etc. By means of a changeover contact, the stabiliser control card allows for the acoustic signalling of the following alarms: minimum voltage, maximum voltage, internal overheating and overload on the voltage regulator.
Voltage control and stabilisation, performed on the true RMS value, are managed by the microprocessor.