Patent ID: 8005630
Filing Date: 2011-08-23
Classification: H02P

Abstract:
1. A system identification device comprising: a speed command generator for outputting a speed command; a differentiator for inputting a position of an electric motor detected by a position detector and then outputting a speed; a speed controller for inputting the speed command and the speed and then outputting a torque command; a torque controller for inputting the torque command and then driving the electric motor with an electric motor current; and an inertia moment and viscous friction identifier for inputting the torque command, the position and the speed, and then calculating and outputting identification values of an inertia moment in the electric motor and a viscous friction, wherein the inertia moment and viscous friction identifier includes: a position amplitude calculator for inputting the position and then calculating and outputting a position amplitude to be an amplitude of a fundamental frequency component of the position; a position torque command integral value multiplier for inputting the position and the torque command, and then calculating and outputting a position torque command integral value multiplication value to be a multiplication value of the fundamental frequency component of the position and an Nth-order time integral value of the torque command, wherein N is set to a natural number including zero; a position torque command integral value average calculator for inputting the position torque command integral value multiplication value and then calculating and outputting an average of a position torque command integral value to be a one-cycle average of the input signal; a speed torque command integral value multiplier for inputting the torque command and the speed, and then calculating and outputting a speed torque command integral value multiplication value to be a multiplication value of a fundamental frequency component of the speed and the Nth-order time integral value of the torque command; a speed torque command integral value average calculator for inputting the speed torque command integral value multiplication value, and then calculating and outputting an average of a speed torque command integral value to be a one-cycle average of the input signal; and a first inertia moment and viscous friction calculator for inputting the position amplitude, the average of the position torque command integral value and the average of the speed torque command integral value, and then calculating and outputting the identification values of the inertia moment and the viscous friction.