Control Method of Deep-Sea Vector Propulsion Motors Based on Position-Sensorless and Variable Carrier Frequency

Abstract

In order to improve the stability and stealth of vector propulsion motors in deep-sea exploration, a control method of deep-sea vector propulsion motors based on the position-sensorless and variable carrier frequency was derived from surface-mounted permanent magnet synchronous motors by using periodic spread spectrum modulation technology and position-sensorless control technology of improved sliding mode observer. Through simulations of motors’ variable carrier frequency, motor start-up speed variation, and sudden load change, the control effects of the proposed method were analyzed. The simulation results show that the rotation speed estimation of the studied control method is accurate, and the method has good dynamic tracking performance for rotation speed. The estimation error rate at the rated rotation speed is only 0.32%, and the estimation error rate at 0.5 times the rated rotation speed is only 0.09%. In addition, the proposed control method has an obvious high frequency harmonic spread spectrum suppression effect and good dynamic anti-interference performance. Combined with the simplification effect of reducing the motor structure brought by the position sensor, the control method proposed in this paper can effectively lower the failure rate of the deep-sea vector propulsion motor during operation, reduce the high-order fixed frequency harmonics that are easy to be detected, improve the reliability and stealth of the deep-sea vector propulsion motor, and provide efficient and reliable power guarantee for deep-sea unmanned undersea vehicles.

Keywords

• vector propulsion motor
• sliding mode observer
• position-sensorless
• variable carrier frequency
• deep sea