In this paper

an algorithm with the function of automatic interlock and protection for 2-phase stepper motor control is described.The algorithm is used in the frequency tuning loop of superconductivity RF cavity.The design mainly uses FPGA to constitute the pulse distributor and ascends frequency step by step to make the stepper motor have a smooth transition from low frequency startup station to the stable working state.Also

it has the function of automatic interlocking and protection to prevent the stepper motor from going beyond the limit

by setting additive interlocking signals.Test results show that by optimizing and setting different startup frequency and different ascending frequency speed

the stepper motor works stably in the superconductivity RF cavity of SSRF.