Part Number:DRV8308
Dear Expert,
We use DRV8308 for BLDC. It is 28VDC 4000W drive. We use 3 Hall effect sensors.
We need to provide certain torque in a wide range of RPM. We do not control torque, but must satisfy the load demand. We do it in nominal and high line. At low line, about 24VDC, the PWM reaches its limit and motor can't put out more power. The controller senses out-of-lock condition and switches from (1) Hall to (3) Hall operation. As a result there is an erratic operation, "hick-up" mode. We operate in close loop mode, setting the speed as a control parameter.
Is it possible to detect imminent "out-of -lock" event ( running out of pulse width) ? If we do that, we can command "reduce speed operation", thereby reducing current, and maintaining below "saturation" operation.
Regards,
Andrei
