Patent ID: 9459181
Filing Date: 2016-10-04
CPC Classification: B60C,G01L,G01M

Claim Text:
1. A drive train testing system comprising: a dynamometer that is connected to an output shaft of a test piece; an inverter that supplies electric power in response to a command signal to the dynamometer; an axial torque detector that detects an axial torque acting on the output shaft; a speed detector that detects a rotation speed of the dynamometer; a tire speed calculation unit that calculates speed values of first and second tires respectively connected to a pair of output shafts of a virtual differential device connected to the output shaft of the test piece; a vehicle speed calculation unit that calculates a speed value of a virtual vehicle traveling by using the first and second tires as drive wheels; a vehicle driving torque calculation unit that calculates a first vehicle driving torque value generated by a friction force between the first tire and a virtual first road surface and a second vehicle driving torque value generated by a friction force between the second tire and a virtual second road surface based on the first and second tire speed values and the vehicle speed value; a differential torque calculation unit that calculates a first differential torque value and a second differential torque value generated in the pair of output shafts of the differential device based on a detection value of the axial torque detector; and a speed control device that outputs a command signal so that a deviation between a detection value of the speed detector and a speed command value calculated based on the first and second tire speed values disappears, wherein the tire speed calculation unit calculates the first tire speed value based on the first differential torque value and the first vehicle driving torque value and calculates the second tire speed value based on the second differential torque value and the second vehicle driving torque value.