A New Method of Generating Pulse Sequence for Numerical Controllers

Abstract

This paper proposes a new algorithm of generating pulse sequence for numerical controllers. Different from the existing algorithms using which the generated pulse frequency is fixed at one displacement increment, the proposed algorithm can generate pulse sequence with real-time changing frequency following the reference displacement command, so that fast-changing velocity requirements in machining can be satisfied. Moreover, by adopting the proposed algorithm, the generated velocity and acceleration can be also controlled within the range of the motor system to achieve better performance. Structure and parameters of the numerical controller which adopts the proposed algorithm are thoroughly discussed in this paper, and methods of adjusting the controller parameters to adapt to the servo system's torque-frequency characteristic are also introduced. At last, effectiveness of the proposed algorithm and effectiveness of the proposed methods for velocity and acceleration control are demonstrated by simulations.

Keywords

• pulse generation
• velocity control
• acceleration control
• servomotor system