Rate limited common mode control for pulse-width modulation drives

摘要

A method for pulse width modulation control of a multiple phase drive includes identifying at least one phase from the plurality of phases for the drive as eligible for clamping to one of a plurality of extreme power supply voltages, selecting a phase of the eligible phases having a largest magnitude driving current, determining a first offset signal as a difference between a control signal level for the selected phase and an extreme control signal level corresponding to one of the extreme power supply voltages, limiting a rate of change of the first offset signal to form a second offset signal, and determining a modified control signal for each of the phases for the drive including forming for each of a plurality of the phases a combination of the second offset signal and a control signal level for the phase to determine the modified control signal for the phase.

主权项

1. A method for pulse width modulation control of a multiple phase drive comprising:
identifying a set of at least one phase from the plurality of phases for the drive as eligible for clamping to one of a plurality of extreme power supply voltages; selecting a phase from the set of eligible phases having a largest magnitude driving current of the set of eligible phases; determining a first offset signal as a difference between a control signal level for the selected phase and an extreme control signal level corresponding to one of the plurality of extreme power supply voltages; limiting a rate of change of the first offset signal to form a second offset signal; and determining a modified control signal for each of the phases for the drive including forming for each of a plurality of the phases a combination of the second offset signal and a control signal level for the phase to determine the modified control signal for the phase.