regeneration with bldc motorcontroller and foc

[PowerPedro]

Regulating a PMBLDC-Motor towards constant torque using the well known FOC-algorithm (field oriented control)and 20kHz-SVPWM for generation of the three phase-currents by three complementarily steered fet-halfbridges is state of the art. But how about the opposite direction of currentflow resp. breaking and charging the battery? Two questions arise: 1. Can the same hardware and the same software be used to generate breake-torque and to charge the battery simply by changing the sign of the target-torque? 2. Is there a need for special hardware to produce a voltage higher than the battery-voltage for charging the battery, especially at low turns? Practically proved comments are highly wellcome.

 

[Lebowski]

1. yes
2. no

when in regen the 6 FETs, motor inductances and motor back-emf all together work like 3 parallel DCDC boost converters.