Patent ID: 7403403
Filing Date: 2008-07-22
Classification: H02M,H03H

Abstract:
1. A noise suppressor comprising: a first winding wire being disposed on a first current-carrying wire; a series circuit including a capacitor and a second winding wire which are connected to each other in series, the series circuit having one end connected to the first current-carrying wire and the other end connected to a second current-carrying wire; and a core around which the first winding wire and the second winding wire are commonly wound, wherein the first winding wire and the second winding wire are magnetically coupled directly to each other via the core, and the inductance of the whole second winding wire is set to be smaller than the inductance of the whole first winding wire, the first winding wire and the a parasitic capacitor of the first winding wire equivalently form a parallel resonant circuit, and the second winding wire and the capacitor in the series circuit and a parasitic inductor of the capacitor equivalently form a series resonant circuit, fh>f is satisfied, where the coupling coefficient between the first winding wire and the second winding wire is k fhm≧fm is satisfied, where the resonant frequency of the whole series resonant circuit in the case where the first winding wire and the second winding wire are magnetically coupled to each other is fhm, and the resonant frequency of the parallel resonant circuit in the case where the first winding wire and the second winding wire are magnetically coupled to each other is fm.