Control of multi-speed transmission

摘要

Apparatus and method for efficiently controlling an automatic transmission in an electric vehicle. The method may be implemented by selection of one of at least two belt clutches having different ratios. The timing for disengagement and engagement of each clutch and the proper sequencing of the disengagement and engagement of the clutches is determined to optimize the efficiency of the transmission. A direct drive motor is directly coupled to the transmission's output shaft to provide momentary power to maintain a nearly constant rate of acceleration during shifting. The method may further be applied for shifting an electric vehicle with a first motor coupled to an output shaft through a single belt clutch and a direct drive motor.