Patent ID: 8379417

Claim:
A power conversion system, comprising: a rectifier comprising a rectifier input to receive AC electrical input power, a rectifier DC output with first and second DC output nodes, and a plurality of rectifiers or switching devices individually coupled between the rectifier input and one of the DC output nodes to provide DC output power at the rectifier DC output; an inverter comprising an inverter DC input with first and second DC input nodes, an AC output, and an inverter switching network comprising a plurality of inverter switching devices individually coupled between one of the DC input nodes and the AC output to provide AC output power to the load; and a DC link choke comprising at least four coils coupled between the rectifier DC output and the inverter DC input, the DC link choke comprising: a core structure comprising: a first leg including first and second ends and an intermediate portion disposed between the first and second ends, a second leg including first and second ends and an intermediate portion disposed between the first and second ends, a third leg extending between the first ends of the first and second legs, and a fourth leg extending between the second ends of the first and second legs, at least one shunt providing a magnetic flux path between intermediate portions of the first and second legs, the at least one shunt extending between and spaced from the intermediate portions of the first and second legs, and forming a plurality of gaps between the intermediate portions of the first and second legs and the at least one shunt, a first winding forming a first coil coupled between the rectifier DC output and the inverter DC input, the first winding having a first terminal and a second terminal and forming at least one turn around the first leg between the intermediate portion and the first end of the first leg, a second winding forming a second coil coupled between the rectifier DC output and the inverter DC input, the second winding having a first terminal and a second terminal and forming at least one turn around the first leg between the intermediate portion and the second end of the first leg, a third winding forming a third coil coupled between the rectifier DC output and the inverter DC input, the third winding having a first terminal and a second terminal and forming at least one turn around the second leg between the intermediate portion and the first end of the second leg, and a fourth winding forming a fourth coil coupled between the rectifier DC output and the inverter DC input, the fourth winding having a first terminal and a second terminal and forming at least one turn around the second leg between the intermediate portion and the second end of the second leg.