Study Of The Rudder Using A Sensorless Brushless Dc Motor Controller

The dissertation proposes a speed-adjusting controller of a low power sensorless and brushless DC motor (SLBLDCM) composed of rare earth permanent magnet which supply motivity for fish torpedo's helm. The dissertation summarizes the developing state of SLBLDCM and the problem for more studied. Considering the feature of the torpedo motor for helm and the engineering application, the operational theory of SLBLDCM working in the 2-phase feed up, all bridge star style 3-phase 6 states and the PWM speed-adjusting theory is particularly analysed. Then, the mathematics model and the Matlab simulation model of SLBLDCM system are established, and the waveforms of current,speed and torque are compared. Additional, basing on other approach to detect rotor position, I research techno-detail of direct back EMF's zero. On account of high speed , the dissertation chooses a new approach to compensate larger scope phase. Finally, hardware and software of a speed-adjusting controler are designed , which use the TMS320LF2407 .