Discontinuous pulse width modulation

摘要

A discontinuous pulse width modulation technique is used in a controller to control an inverter that converts DC battery power to AC power to operate an electric motor, e.g., in a hybrid electric vehicle. The discontinuous pulse width modulation technique uses only one of the two zero state voltage vectors in its calculations whereas traditional pulse width modulation uses both zero state voltage vectors. The use of a single zero state voltage vector can result in one of a group of switches in the inverter remaining in a constant state during a complete duty cycle while still providing the commanded voltage vector to the electrical motor. As a result losses due to switching can be reduced.

主权项

1. A vehicle discontinuous PWM method comprising:
outputting a voltage-command to control an electric motor using two adjacent active vectors and a single zero-vector associated with the two active vectors, and to include a vector angle that is proportional to a sum of rotor position and an output of a commanded vector angle and a sector dependent parameter; and alternating the single zero-vector for calculating the voltage-command for subsequent adjacent active vectors of an adjacent sector.