Patent ID: 6873126
Filing Date: 2005-03-29
Classification: H02P

Abstract:
1. A motor drive method for a motor driver having a plurality of output circuits each including an upper side switching element and a lower side switching element connected in series, and a current detection resistance connected in series with the plurality of output circuits in common for detecting a current supplied to the plurality of output circuits, the motor driver supplying a current to a motor from a connection point between the upper side switching element and the lower side switching element of each of the output circuits, the motor drive method comprising the steps of: determining a position signal corresponding to the position of a rotor of the motor; selecting one switching element of one of the plurality of output circuits according to the position, signal and turning ON the selected switching element for a time period corresponding to a predetermined electrical angle; and repeatedly switching lower side switching elements of a plurality of output circuits among the remaining ones of the plurality of output circuits when the selected switching element is an upper side switching element, while repeatedly switching upper side switching elements of a plurality of output circuits among the remaining ones of the plurality of output circuits when the selected switching element is a lower side switching element, wherein in the switching step, the switching operation is controlled according to an input torque command signal and a voltage generated at the current detection resistance so that each of a plurality of periods obtained by dividing the time period corresponding to the predetermined electrical angle includes a first period in which one of the switching elements to be switched is turned ON and a second period in which another one of the switching elements is turned ON.