A device includes an EMC (electromagnetic compatibility) filter, a frequency converter coupled to the EMC filter, and a motor coupled to the frequency converter via a motor cable. A leakage current compensator includes a leakage current detector and a compensation current generator configured to generate a compensation current that is directed against the leakage current and is overlaid on the leakage current in such a way that the leakage current is reduced.

A cable distribution plant is protected from noise where a modem housing encloses a switching power supply and digital electronics, the modem switching power supply for receiving AC mains power via an EMI filter and modem digital electronics for receiving a switching power supply output via an LC filter for filtering noise at the switching power supply frequency wherein multiple filters used with respective modems at subscriber sites protect the head-end from switching power supply harmonic noise otherwise aggregated by the nodes and passed to the head end.

A transient noise reduction filter comprises a cable including one or more twisted pairs of conductors and one or more common mode chokes (CMCs). The one or more CMCs a formed from respective pluralities of turns of the cable. Each of the CMCs may be a magnetic CMC wherein the plurality of turns of the cable are wrapped around a magnetic core, or an air-core CMC wherein the plurality of turns of the cable are not wrapped around a magnetic core but are instead disposed around a non-magnetic material (such as air)

A common mode choke assembly includes a main core, a shunt core, and first and second two-piece bobbins. The main core has a generally rectangular main core body, and first and second core riser portions. The first and second core riser portions are connected to opposite ends of the main core body. The first core riser portion includes a first riser notch and the second core riser portion includes a second riser notch aligned with the first riser notch. The shunt core spans between and is positioned within the first and second riser notches. The first and second two-piece bobbins are positioned on opposite sides of the main core body adjacent to the first and second core riser portions. Each two-piece bobbin includes at least first and second end flanges, a passageway, and a mating surface. The assembly further includes a mounting header for receiving the main and shunt core.

A differential mode electromagnetic noise injection network includes an injection piece and a differential mode loop. The injection piece includes a semiconductor transistor or a winding differential mode inductor. The injection piece is at least provided with a first injection end, a second injection end, and a differential mode electromagnetic noise component input end. The differential mode electromagnetic noise component input end is configured to input a differential mode electromagnetic noise component. The first injection end and the second injection end are connected to any two points that are connected in series in the differential mode loop in a one-to-one correspondence, and are configured to inject the differential mode electromagnetic noise component. An active electromagnetic interference filter including the differential mode electromagnetic noise injection network mentioned above is provided.

A noise suppression filter includes a resonator, a ground plane, and a set of differential transmission lines. The set of differential transmission lines includes a first meander line and a second meander line formed in a first circuit layer. The resonator is formed in a second circuit layer and includes a first long arm, a second long arm, and a short arm extended form a same point to form a T-shape. The ground plane is formed in a third circuit layer and is coupled to the first long arm and the second long arm through vias. The first meander line is detoured along the inner sides of the first long arm and the short arm, and the second meander line is detoured along the inner sides of the second long arm and the short arm.

A filter assembly includes a first self-inductance core, a second self-inductance core, a coupled inductor core, and a first plurality of inductor coil windings. Each of the first plurality of inductor coil windings has a series of first turns in a vertically stacked relation around the first self-inductance core, and a series of second turns in a vertically stacked relation around the first self-inductance core and the coupled inductor core. The filter assembly further includes a second plurality of inductor coil windings. Each of the second plurality of inductor coil windings has a series of first turns in a vertically stacked relation around the second self-inductance core, and a series of second turns in a vertically stacked relation around the second self-inductance core and the coupled inductor core.

Provided is a filter device to be connected between an AC power source (1) and a PWM converter (2), which includes a first AC reactor (3), a second AC reactor (4) that is connected between the PWM converter (2) and the first AC reactor (3), a filter capacitor (5) whose one end is connected to a connecting portion (9) between the first AC reactor (3) and the second AC reactor (4), and a housing (15) having a cooling air inlet (16) and a cooling air outlet (17) and containing the first AC reactor (3) and the second AC reactor (4), wherein the first AC reactor (3) is disposed upwind of the second AC reactor (4).

The present disclosure provides an inductive element capable of lowering a Q-value. An inductive element includes a first cover and a second cover covering an annular core, and a first winding and a second winding wound around a region of the core, the first cover and the second cover. The first cover covers a part of an inner circumferential surface of the core, a part of an outer circumferential surface and an end surface on one end side in an axial direction. The second cover covers a part of the inner circumferential surface of the core, a part of the outer circumferential surface an end surface on the other end side in the axial direction.

The present disclosure provides a common mode noise filter that can improve attenuation characteristics of common mode noise over a wide frequency range. The common mode noise filter of the present disclosure includes: two magnetic sections and each of which is made of a magnetic material; and non-magnetic section disposed between magnetic sections in a stacking direction, non-magnetic section being made of a non-magnetic material. Moreover, the common mode noise filter further includes two coils and metal layer. Coils are disposed inside non-magnetic section while facing each other. Metal layer is formed inside at least one of two magnetic sections while being connected to the ground. Metal layers are positioned closer to a lower surface of magnetic section than an upper surface of magnetic section and closer to an upper surface of magnetic section than a lower surface of magnetic section.