# Motor-side of BLAC supply goes into overvoltage when regenrative braking using an LM5060

I am currently using an LM5060 for protection of the motor supply on my BLAC motor driver. Everything works well until I decelerate the motor quickly, this makes the supply voltage peak above the OVP and cuts off the power. What are best practices when it comes to protecting the motor supply? Should I consider only using reverse polarity protection? Or should I increase the OVP threshold? Thanks!

• Where are you putting the energy from the re-gen braking? If into a resistor, then you need to tune the resistor better (resistance value will vary a lot depending on how much braking you're doing), if into a battery, you need to tune how your current control (assuming that is your method for controlling the braking). Either way, the design should be tuned for your system, probably with a clamping diode to protect things as a fail safe. – Puffafish Mar 22 at 8:12
• What value bulk capacitor do you have on your H bridge/motor driver? You should consider showing your circuit. – Andy aka Mar 22 at 10:06
• @Andyaka I have a total bulk capacitance of 202uF. It's difficult showing my circuit since its divided into several schematic sheets. I could provide you with a high-level block diagram perhaps? – Alex Er Mar 22 at 10:37
• @Puffafish I do not currently have an RBrake. We want to use this energy to recharge the battery. But should we be more mindful of the way we decelerate? Like making sure we don't do it too suddenly and etc? EDIT: accidental enter – Alex Er Mar 22 at 10:38
• If you are going to add a full RBrake system to charge a battery you need to do a full control system taking into account the speed of the motor and so on. Unless whatever you're doing as very low energy, so not worth putting the energy into a battery, you will need quite a complex control algorithm. Personally I've done it when I have a current control method to push power into the battery, constantly changing depending on the speed of the shaft. – Puffafish Mar 22 at 12:05