Inductor assembly

1. An inductor assembly for a converter, the assembly comprising:

a plurality of first conductors arranged on respective legs of a first magnetic core;

a second magnetic core with one or more legs, the second core magnetically coupled to the first core via an air-gap and arranged to provide a path for common mode magnetic flux of the plurality of first conductors; and

a respective second conductor corresponding to each of the plurality of first conductors;

wherein each pair of first and second conductors is electrically connected in series; and

the second conductors are arranged on a single leg of the second core and positively coupled to each other.

2. The inductor assembly of claim 1 , wherein pairs of the first conductors are inversely coupled to one another.

3. The inductor assembly of claim 1 , wherein the pairs of corresponding first and second conductors are positively coupled.

4. The inductor assembly of claim 1 , wherein the second core is LL-shaped.

5. The inductor assembly of claim 1 , wherein:

each pair of the corresponding first and second conductors is inversely coupled; and

the second core comprises at least two legs.

6. The inductor assembly of claim 5 , wherein the second core comprises exactly two legs.

7. The inductor assembly of claim 6 , wherein the second core is FF shaped.

8. The inductor assembly of claim 1 , wherein:

the first magnetic core comprises a first core material; and

the second core comprises a second core material different from the first core material.

9. The inductor assembly of claim 1 , wherein the second core at least partially surrounds the first magnetic core.

10. The inductor assembly of claim 1 , wherein:

the second core includes a multi-leg core in a first direction; and

at least some of the plurality of first cores are arranged to extend in a second direction to be magnetically coupled to the legs of the second core.

11. The inductor assembly of claim 10 , wherein:

at the locations of the legs the second core is LL-shaped with the arms of the LL shape extending in the second direction; and

the first cores are arranged adjacent to the arms of the LL shape.

12. The inductor assembly of claim 10 , further comprising a third core shaped like the second core and arranged adjacent to the second core in the second direction on a side opposite to the plurality of first cores.

13. A multiple phase converter comprising:

an inductor assembly comprising:

a plurality of first conductors arranged on respective legs of a first magnetic core;

a second magnetic core with one or more legs, the second core magnetically coupled to the first core via an air-gap and arranged to provide a path for common mode magnetic flux of the plurality of first conductors; and

a respective second conductor corresponding to each of the plurality of first conductors;

wherein each pair of first and second conductors is electrically connected in series;

the second conductors are arranged on a single leg of the second core and positively coupled to each other;

the first core has a respective leg for each of the phases; and

each of the plurality of first conductors corresponds to one of the phases.

14. A multiple phase converter according to claim 13 , wherein:

the multiple phase converter comprises a three-phase converter; and

the first core is EE shaped with three legs.

15. A multiple phase interleaved converter comprising:

a plurality of modules; and

an inductor assembly comprising:

a plurality of first conductors arranged on respective legs of a first magnetic core;

a second magnetic core with one or more legs, the second core magnetically coupled to the first core via an air-gap and arranged to provide a path for common mode magnetic flux of the plurality of first conductors; and

a respective second conductor corresponding to each of the plurality of first conductors;

wherein each pair of first and second conductors is electrically connected in series;

the second conductors are arranged on a single leg of the second core and positively coupled to each other;

additional first cores for each of the plurality of modules;

wherein the respective first conductors on each of the first cores correspond to a phase of the respective module;

the second core comprises a respective leg for each of the modules; and

the second conductors on each leg correspond to the respective module.