Patent ID: 9140731
Filing Date: 2015-09-22
Classification: G01R,H02J

Abstract:
1. Apparatus for measuring impedances of respective phases of a multi-phase electrical power system at any system interface between stages of said multi-phase electrical power system, said apparatus comprising a phase locked loop for aligning a frame of reference with an input power vector and a plurality of angles, a sweep generator responsive to said phase locked loop for applying perturbations at said angles to which said frame of reference is aligned to respective phases of said system interface over a range of frequency whereby an angle of said perturbation is controlled, in sequence, to said multi-phase electrical power system, said perturbations being applied through amplifiers, voltage and current sensors for measuring amplitude and phase of the voltage and current responses to respective said perturbations, and a computer to compute impedances of respective phases of said interface from phase and amplitude of voltage and current responses to said perturbations over said range of frequency of respective said perturbations.