Patent ID: 11967913
Assignee: EXRO TECHNOLOGIES INC.
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A system to drive a multiphase electric machine, the multi-phase electric machine having a respective plurality of coils for each phase, the system comprising a respective coil driver for each phase, each coil driver respectively comprising:
a DC energy store coupled between ports of the coil driver;
a first switch pair, the first switch pair having at least two switches connected in series between the ports of the coil drive and having a first node between the at least two switches;
a second switch pair, the second switch pair having at least two switches connected in series between the ports of the coil drive and having a second node between the at least two switches, wherein a first AC drive current or a first AC voltage for a first coil is generated between the first node and the second node;
a third switch pair, the third switch pair having at least two switches connected in series between the ports of the coil drive and having a third node between the at least two switches;
a fourth switch pair, the fourth switch pair having at least two switches connected in series between the ports of the coil drive and having a fourth node between the at least two switches, wherein a second AC drive current or a second AC voltage for a second coil is generated between the third node and the fourth node;
a fifth switch pair, the fifth switch pair having at least two switches connected in series between the second node and the third node;
wherein:
in a first mode, the first switch pair, the fourth switch pair, and the fifth switch pair are in an ON state and the second switch pair and the third switch pair are in an OFF state, and
in a second mode the first switch pair, the second switch pair, the third switch pair, and the fourth switch pair are in an ON state, and the fifth switch pair are in an OFF state forming two H bridges, and
wherein in the first mode the first and the second AC voltages have a frequency factor that is twice a drive modulation frequency of the switches.