The Research Of High-quality Dual-redundancy Rudder Servo System

Missile rudder is the executive part of missile flying system, and is close to the attack precision of the missile.This dissertation introduces the background and significance of the research and the present situation and developing prospect of the EMA Servo. In the paper, a set of fully-digital-signal servo system for missile rudder based on DSP (TMS320F2812) is designed in accordance with the high accuracy position servo. The structure and principle of the electric steering engine and dual-redundancy motor is also introduced. On the basis of the brief introduction of the math model of BLDCM with one winding and double windings, the dynamical mathematics model for BLDCM according to the state equation is provided, some simulation waveforms and results are acquired, meanwhile, the theoretical analysis of some system faults such as inverter switch failure, winding failure and position sensor failure is given. According to the general design, the detailed system hardware and software design is finished, the position servo's digital control and the function of the double windings' current balance is realized, the system possesses certain ability of redundancy management and fault tolerant.In hardware design, the construction process of the whole servo with TMS320F2812 DSP as the core controller is explained, and the key part is analyzed in detail; the CPLD control logic is designed, and the waveform by simulation based on maxplus-II is also provided. In software design, the paper discusses the integrated embedded software development environment for Texas Instrument's TMS320 series DSP firstly, and the resources of DSP we used secondly. The main algorithm — completely-digital triple-loop control, composed by current loop, velocity loop and position loop is adopted. And the multi-mode PID control algorithm is used concretely in view of the nonlinearity and time-change nature. Especially in the current loop design, average current injection method is adopted, and the method is quite convenient to solve the current balance problem. Meanwhile, the redundancy management is facilitated. Finally, the experiment results are analyzed and it's proved that the system possesses strong robustness and good dynamic-static performance.At the end of the paper, all factors which affect the system performance are analyzed, and optimization designs are presented.