| 摘要 |
PROBLEM TO BE SOLVED: To prevent any decrease in control accuracy due to current sensor noise and to reduce the cost by decreasing the number of parts by freely setting the response of the current control for servo motor by changing time constant in the current drive for the servo motor by using a reverse operation system of the servo motor and the primary delay element. SOLUTION: A current command Icmd is input to a first arithmetic operator 10 through a reverse arithmetic system (Ra+Las) of the arithmetic system of a servo motor 4 and a primary delay element (1/1+τs, where τ is time constant, and s is Laplace operator). And the output 10a of a first operator 10 is input to a second operator 11. And the output 11a of the second operator 11 obtains a motor speed ω through the arithmetic system (1/Ra+Las), torque constant Kt and inertia 1/Js. And the response of a current loop of the servo motor 4 becomes a primary delay element (1/1+τs), and a current control system following up the current target value accurately and freely can be obtained by changing the time constant τ. |
