RUNAWAY PREVENTING SYSTEM OF AC SERVO MOTOR

摘要

PURPOSE:To eliminate the acceleration of a motor by providing a runaway discriminator for detecting the abnormal state (runaway) of the motor in a CPU to stop generating a torque immediately when the runaway is detected. CONSTITUTION:A speed amplifier 100 is composed of a CPU. A motor sped and a torque command value are recorded in a memory in a runaway discriminator 102 together with the magnitude and the direction, and a discrimination signal from a counter 103 is fed to the discriminator 102 at every certain time TR, the magnitude and code of the values are compared to discriminate whether there is a sign of the runaway or not, and when it exceeds the allowable range, the discriminator 102 delivers a base block signal BBS to operate a gate circuit 400 provided between a current amplifier 200 with 2 phase/3 phase converter and a power switching element 300 to interrupt the power source of the motor 2 to prevent the runaway.