| CPC H02P 29/0241 (2016.02) [H02P 27/08 (2013.01); H02P 29/028 (2013.01); H02M 7/5387 (2013.01)] | 19 Claims |
|
1. A circuit for a multi phase bridge inverter having a plurality of high side switches arranged to be coupled to a first power source busbar and a plurality of low side switches arranged to be coupled to a second power source busbar, wherein the multi phase inverter is arranged to control current flow in coil windings of an electric motor, and wherein a DC link capacitor is coupled between the first power source busbar and the second power source busbar, the circuit comprising:
a first impedance and a second impedance coupled in series between the first power source busbar and the second power source busbar and in parallel to the DC link capacitor and configured for providing a voltage from the coupling between the first impedance and the second impedance to the plurality of low side switches upon the occurrence of a first predetermined condition to place the plurality of low side switches in a close circuit configuration to allow coil windings of the electric motor to be placed in a short circuit configuration or to the plurality of high side switches upon the occurrence of a first predetermined condition to place the plurality of high side switches in a close circuit configuration to allow coil windings of the electric motor to be placed in a short circuit configuration; and
a controller and a first switch, wherein the switch is coupled between the first power source busbar and the first impedance and the controller is arranged to close the switch upon a second predetermined condition;
wherein the second predetermined condition is a voltage difference between the first power source busbar and second power source busbar increases above a predetermined value.
|