Control unit for controlling an inverter, regenerative braking system for a vehicle and method for charging a battery

Abstract

In one embodiment, a control unit (6) for controlling an inverter (4) connected between the battery (3) and the motor (5) for increasing the back EMF generated by the motor (5) and for charging the battery (4) comprises an inverter (4) comprising a first, second and third half-bridge circuit (7, 8, 9) connected in parallel between a low-voltage bus (17) and a high-voltage bus (6), each of the first, second and third half-bridge circuits (7, 8, 9) having a high-side switch (S1, S3, S5) and a low-side switch (S2, S4, S6) coupled to a node (10, 11, 12) which is each coupled to a first, second and third phase of the motor (5), respectively.The control unit (6) is configured as follows: when the first phase of the motor is energized, in a first sector (A), it switches off the high-side switch (S1, S3, S5) of the first, second, and third half-bridge circuits (7, 8, 9), switches off the low-side switch (S6) of the third half-bridge circuit (9), and switches on the low-side switch (S2, S4) of the first and second half-bridge circuits (7, 8) to increase the back EMF, and then (B) it switches on the high-side switch (S1) of the first half-bridge circuit (7) and switches off the low-side switch (S2, S4) of the first and second half-bridge circuits (7, 8) to charge the battery (3), with the high-side switch (S3, S5) of the second and third half-bridge circuits (8, 9) and the low-side switch (S6) of the third Half-bridge circuit (9) remain switched off.

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