SLAU948 October 2024 MSPM0G3507
In applications where the power supply fluctuates, user needs to specify the minimum and maximum power supply voltage range. During an undervoltage condition, the motor operates in overmodulation region to achieve the target speed leading to current distortion, inefficiency or noise. During an overvoltage condition, the MOSFETs and motor are stressed with continued operation in high voltage.
Tuning Under Voltage Limit 1: Keep decreasing the supply voltage until there is a drop in the speed. Measure the bus voltage at which the speed drops and set MIN_VM_MOTOR to that value. Range of minimum bus voltage that can be configured is between 0 to 25% of Maximum BASE_VOLTAGE.
Tuning Over Voltage Limit: Keep increasing the bus voltage to a point where the motor phase voltage reaches the maximum rated voltage of the motor. MAX_VM_MOTOR is the bus voltage at which motor phase voltage reaches the maximum rated voltage of the motor. Range of maximum bus voltage that can be configured is between 60% to Maximum BASE_VOLTAGE.
The FOC Algorithm provides an undervoltage recovery mode [MIN_VM_MODE] and an overvoltage recovery mode [MAX_VM_MODE]. Undervoltage recovery mode can be configured to either automatically clear Undervoltage fault [MTR_UNDER_VOLTAGE] or latch on Undervoltage fault. Overvoltage recovery mode can be configured to either automatically clear Overvoltage fault [MTR_OVER_VOLTAGE] or latch on Overvoltage fault.