Abstract: An air core dry type power reactor comprises upper and lower spider units and a coil including a plurality of cylindrically shaped winding layers including an outermost layer. The reactor further comprises a double wall sound shield including concentric a first roving cylinder and a second roving cylinder, the first roving cylinder positioned against the outermost layer but detached from the coil by a first airgap between the outermost layer and the first roving cylinder to reduce a structure-borne transmission of an acoustic energy or attached by ductsticks to the coil. The second roving cylinder is placed at a distance from the first roving cylinder to form an acoustic cavity between two double walls of the first roving cylinder and the second roving cylinder. The double wall sound shield further including a plurality of sound absorbent panels to attenuate resonances of the acoustic cavity between the two double walls of the first roving cylinder and the second roving cylinder.

Abstract: An air core dry type power reactor comprises upper and lower spider units and a coil including a plurality of cylindrically shaped winding layers including an outermost layer. The reactor further comprises a double wall sound shield including concentric a first roving cylinder and a second roving cylinder, the first roving cylinder positioned against the outermost layer but detached from the coil by a first airgap between the outermost layer and the first roving cylinder to reduce a structure-borne transmission of an acoustic energy or attached by ductsticks to the coil. The second roving cylinder is placed at a distance from the first roving cylinder to form an acoustic cavity between two double walls of the first roving cylinder and the second roving cylinder. The double wall sound shield further including a plurality of sound absorbent panels to attenuate resonances of the acoustic cavity between the two double walls of the first roving cylinder and the second roving cylinder.

Abstract: A noise mitigating sound shield comprises an assembly configured for attachment to an air-core dry-type reactor. The assembly is configured for forming a closed cylinder positioned radially outward from an outermost surface of a reactor build of the air-core dry-type reactor. The assembly includes a noise attenuating barrier having an innermost surface. No portion of the outermost surface of the reactor build directly contacts the innermost surface of the noise attenuating barrier limiting structure-borne sound transmission from the reactor build to the noise attenuating barrier.

Abstract: A noise mitigating sound shield comprises an assembly configured for attachment to an air-core dry-type reactor. The assembly is configured for forming a closed cylinder positioned radially outward from an outermost surface of a reactor build of the air-core dry-type reactor. The assembly includes a noise attenuating barrier having an innermost surface. No portion of the outermost surface of the reactor build directly contacts the innermost surface of the noise attenuating barrier limiting structure-borne sound transmission from the reactor build to the noise attenuating barrier.

Abstract: An air core reactor (47) including a plurality of concentric conductor winding packages (44, 46) wherein a force (F+) generated by the interaction of current (+) flowing through one package and a magnetic field (42) generated by the reactor is out of phase (F?) with a force generated in another package, thereby effectively mitigating audible sound generated by power operation of the reactor. In one embodiment (FIG. 3), the out of phase force may be generated when at least one winding (38c, 37d) of one package (38) is configured to conduct a current (?) that is at least 10 degrees out of phase with a current (+) conducted by another package (40) or other windings (38a, 38b) of the reactor (36).

Abstract: An air core reactor (47) including a plurality of concentric conductor winding packages (44, 46) wherein a force (F+) generated by the interaction of current (+) flowing through one package and a magnetic field (42) generated by the reactor is out of phase (F?) with a force generated in another package, thereby effectively mitigating audible sound generated by power operation of the reactor. In one embodiment (FIG. 3), the out of phase force may be generated when at least one winding (38c, 37d) of one package (38) is configured to conduct a current (?) that is at least 10 degrees out of phase with a current (+) conducted by another package (40) or other windings (38a, 38b) of the reactor (36).