METHOD AND SYSTEM FOR CALIBRATING VOLTAGE MEASUREMENTS IN A SYSTEM FOR MEASURING ELECTRICAL QUANTITIES

A system for calibrating voltage measurements in a system for measuring electrical quantities includes a calibration device configured to determine a first reference time instant of a zero-crossing event of a voltage signal that it measures, and transmit a calibration message including the first reference time instant and a measured voltage amplitude value to at least one device for measuring electrical quantities. The at least one device for measuring electrical quantities is configured to receive the calibration message, extract the first reference time instant and the voltage amplitude, determine a second reference time instant, of zero crossing of the voltage signal measured locally, corresponding to the first reference instant, calculate a phase shift of the locally-measured voltage signal, as a function of the difference between the first and the second reference time instants and apply a phase and amplitude voltage calibration as a function of the voltage amplitude and of the phase shift.