Patent Document ID: 8067932
Application ID: 12513531
Patent Flag: 1

Claim One:
1. A real-time grid monitoring systems for multi-phase applications comprising: a multi-phase (abc) to two-phase (αβ) transformation processor responsive to the multi-phase input voltage or current for generating a set of two signals collecting information about the positive and negative-sequence components of the original multi-phase input, wherein the real-time grid monitoring systems further comprises: a dual quadrature signal generator (DQSG), comprising two quadrature signal generators (QSGs) responsive to the αβ input signals for obtaining both the in-phase and the in-quadrature versions of the αβ monitored signals; a frequency adaptive loop, comprising a frequency-locked loop (FLL) responsive to frequency variations in the αβ monitored signals for modifying a tuning frequency of both QSGs in order to make the tuning frequency equal to a fundamental frequency of the αβ monitored signals; a real-time positive-negative-sequence calculator (PNSC) based on an αβ reference frame that is responsive to the in-quadrature signals, wherein said in-quadrature signals are supplied by the DQSG for splitting up the in-quadrature signals into positive and negative-sequence components of the αβ reference frame.