A box-shaped inner case (3) is accommodated in a box-shaped outer case (2), and refrigerant flow passages (27) are formed at five surfaces except an opening surface (24) by gaps between the inner and outer cases. A Gap of an opening edge of the outer case (2) and an opening edge of the inner case (3) is covered with a frame-shaped cover (6). A coil (4) is placed in the inner case (3), and the inner case (3) is filled with magnetic powder mixture resin so that the coil (4) except the terminals (4a, 4b) is embedded. A core (5) is made of the magnetic powder mixture resin. Cooling water flows along a longitudinal direction of the outer case (2) with one of refrigerant pipe connecters (15) being a refrigerant inlet and the other of the refrigerant pipe connecters (15) being a refrigerant outlet.

According to one embodiment, a cooled transformer including: a laminated core comprising a first core extension and a second core extension; a first inner coil circumferentially wrapped around the first core extension; a first outer coil circumferentially wrapped around the first core extension; the first outer coil being located radially outward from the first inner coil; a second inner coil circumferentially wrapped around the second core extension; a second outer coil circumferentially wrapped around the second core extension; the second outer coil being located radially outward from the second inner coil; and at least one cooling plate interposed between the first inner coil and the first outer coil.

According to one embodiment, a cooled transformer including: a laminated core comprising a first core extension and a second core extension; a first inner coil circumferentially wrapped around the first core extension; a first outer coil circumferentially wrapped around the first core extension; the first outer coil being located radially outward from the first inner coil; a second inner coil circumferentially wrapped around the second core extension; a second outer coil circumferentially wrapped around the second core extension; the second outer coil being located radially outward from the second inner coil; and at least one cooling plate interposed between the first inner coil and the first outer coil.

The invention comprises a harmonic filter apparatus and method of use thereof for magnetically isolating and filtering individual phases of three-phase power comprising a delta circuit that includes: (1) a first leg connecting to a second leg and a third leg and (2) first circuitry on the first leg matching second circuitry on the second leg, the first circuitry comprising at least two contactors electrically wired in parallel, the harmonic filter magnetically isolating individual phases of three-phase power, where inductor—coupled inductor pairs couple apexes of the delta circuit to individual phases of the three-phase power.

The invention comprises a harmonic filter apparatus and method of use thereof for magnetically isolating and filtering individual phases of three-phase power comprising a delta circuit that includes: (1) a first leg connecting to a second leg and a third leg and (2) first circuitry on the first leg matching second circuitry on the second leg, the first circuitry comprising at least two contactors electrically wired in parallel, the harmonic filter magnetically isolating individual phases of three-phase power, where inductor—coupled inductor pairs couple apexes of the delta circuit to individual phases of the three-phase power.

The invention comprises a harmonic filter apparatus and method of use thereof, the harmonic filter including a delta circuit comprising: (1) a first leg connecting a first apex to a second apex of the delta circuit; a second leg connecting the second apex to a third apex of the delta circuit; and a third leg connecting the third apex to the first apex and (2) a first electrical contactor and a second electrical contactor positioned within at least two of: the first leg, the second leg;

and the third leg. Optionally and preferably, each apex of the delta circuit is connected to individual phases of three phase power via respective inductor—coupled inductor pairs, where the harmonic filter magnetically isolates individual phases of the three phase power.

The invention comprises a harmonic filter apparatus and method of use thereof, the harmonic filter including a delta circuit comprising: (1) a first leg connecting a first apex to a second apex of the delta circuit; a second leg connecting the second apex to a third apex of the delta circuit; and a third leg connecting the third apex to the first apex and (2) a first electrical contactor and a second electrical contactor positioned within at least two of: the first leg, the second leg;

and the third leg. Optionally and preferably, each apex of the delta circuit is connected to individual phases of three phase power via respective inductor—coupled inductor pairs, where the harmonic filter magnetically isolates individual phases of the three phase power.

The invention comprises a method for fastening an inductor, comprising an aperture therethrough, to a mounting surface with a set of at least two mechanical straps and a strap force of ten to one hundred pounds of force per strap, the step of fastening further comprising the step of: passing at least a first portion of each of a first and second mechanical strap of the set of mechanical straps through the aperture and on opposing sides of the aperture, the first portion comprising a non-conductive material, where the inductor winding is fabricated during installation and/or the inductor is a component of a harmonic filter magnetically isolating and filtering individual phases of three phase power.

The invention comprises a method for fastening an inductor, comprising an aperture therethrough, to a mounting surface with a set of at least two mechanical straps and a strap force of ten to one hundred pounds of force per strap, the step of fastening further comprising the step of: passing at least a first portion of each of a first and second mechanical strap of the set of mechanical straps through the aperture and on opposing sides of the aperture, the first portion comprising a non-conductive material, where the inductor winding is fabricated during installation and/or the inductor is a component of a harmonic filter magnetically isolating and filtering individual phases of three phase power.

The invention comprises a harmonic filter apparatus and method of use thereof for magnetically isolating and filtering individual phases of three-phase power comprising a delta circuit that includes: (1) a first leg connecting to a second leg and a third leg and (2) first circuitry on the first leg matching second circuitry on the second leg, the first circuitry comprising at least two contactors electrically wired in parallel, the harmonic filter magnetically isolating individual phases of three-phase power, where inductor—coupled inductor pairs couple apexes of the delta circuit to individual phases of the three-phase power.