Patent Document ID: 20100213925
Application ID: 12513531
Patent Flag: 0

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; characterized in that the real-time grid monitoring systems further comprises: a dual quadrature signal generator (DQSG), which dual quadrature signal generator comprises two QSGs, which QSGs are 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, which frequency adaptive loop is a frequency-locked loop (FLL), which FLL is responsive to frequency variations in the monitored signals for modifying the tuning frequency of all the QSGs in order to make it equal to the fundamental frequency of the monitored signals. a real-time positive- negative-sequence calculator (PNSC) based on the αβ reference frame, which αβ reference frame is responsive to the in-quadrature signals, which quadrature signals is supplied by the DSQG for splitting up the quadrature signal into their positive and negative-sequence components of the αβ reference frame.