数字式导弹舵机伺服控制器的设计与开发

【作者】 周杰；

【导师】 徐利梅；

【作者基本信息】 电子科技大学 ， 机械电子工程， 2009， 硕士

【摘要】 舵机是导弹伺服控制系统的执行机构,它能根据弹上计算机输出的舵面角度信号,控制弹体的舵翼,依靠弹体飞行中舵翼偏转产生的空气动力及气动力矩,稳定和控制弹体,使弹体按设计的弹道飞行,直至命中目标。可见舵机控制在导弹制导过程中具有极其重要的作用。大多数传统的火箭和导弹一般沿用液压或气压伺服系统,这些伺服系统虽然具比较优良的输出功率和结构适应性,但是具有结构复杂、重量大、成本高、实现技术难度大以及瞬态响应不够迅速等缺点。数字式导弹舵机伺服控制器区别与传统的舵机伺服控制器,采用以数字信号处理器(DSP)和直流电机为基础构建伺服系统,很大程度的简化了系统的结构,从而使其具有体积小、重量轻、稳定性强、精度高、便于调试且在恶劣条件下保持高性能运行等优点,成为近年来国内外舵机研制和开发的热点。本论文的研究内容来源于航天科技集团第七研究院下属某企业针对出口订单需求的某型号导弹数字舵机伺服控制系统的研发任务。本文从硬件和软件两个方面完成了数字式导弹舵机伺服控制器的设计与开发工作,所设计的舵机伺服系统体积小,功耗低、精度高,动态特性优异,各项性能指标均已达到或超出企业的指标要求。系统的零位定位误差为±0.02°仅为要求误差量的1/10;系统空载瞬态响应时间为26ms,弹性负载瞬态响应时间为38ms,都远低于所要求的60ms;系统在0.4V扫频正弦信号输入下的带宽>12Hz。另外,系统在稳定性、抗干扰以及调试性等方面,相对于之前的模拟舵机伺服系统都有了较大提升。在数字舵机伺服控制器的设计中,软件方面,通常的伺服控制器均采用经典的位置-速度-电流三闭环控制策略,然而,这种控制策略在对舵机控制时存在着电流环不易实现和参数不易整定,系统频域跟随精度不高和响应速度不够快的问题。具体控制算法的选择上,传统的PID控制难以同时满足系统快速性和低超调量等问题。本文通过对伺服控制策略和模糊控制理论的研究,采用一种基于双模模糊PID的前馈-位置-速度的复合控制策略,来满足系统高精度、快响应和宽带宽的性能要求。硬件方面,本文完成了数字伺服控制系统中常见的控制电路,功率驱动电路,以及信号采样/调理电路的设计与实现,同时为了确保舵机系统的精度要求,还研发了专用的高精度开关电源。所设计的反激式开关电源输出精度高,纹波的峰值≤±20mV,仅为普通同等级开关电源的1/5。其次,通过硬件抗干扰设计和体积控制,良好的抑制了高频干扰,提高了系统的稳定性,并使控制器体积较原模拟型号缩小1/4。系统实测数据结果的分析与比较证明了本文所提出的硬件设计,控制策略,控制算法在达到系统指标要求,优化系统性能方面的可行性和有效性。更多还原

【Abstract】 Rudder is the actuator of missile servo control system. It is able to control missile wings by air force and pneumatic torque, according to computer command. Thus, missile can cruise in a planned track. Therefore, the servo control of missile rudder plays a very important role in missile guidance.Traditionally, most of missile adopts hydraulic or baric servo system, which has many merits of good dynamic performance and structure adaptability. However, these systems are also have flaws such as complex structure, big volume, high cost, low instantaneous response speed and so on. Compared with these systems, missile rudder digital servo controller is composed by digital signal processor (DSP) and DC motor, which simplifies system structure remarkably. And due to small volume, easy debugging, excellent performance in harsh condition, high stability and precision, the development and research of digital missile rudder servo system has become hot spot recently.This dissertation is mainly on the development of an export certain mode missile rudder digital controller, assignment from a subordinate enterprise of 7th Institute, China Aerospace Science and Technology Corporation. This paper presents the design and development approach on both hardware and software, the designed system, which has the merits such as small volume, low power consumption, high location precision and excellent dynamic characteristic, has already met all system performance requirements. The system zero-error is±0.02°, that means just 1/10 of the error value required; unloaded and elasticity loaded instantaneous response time is 26ms and 38ms respectively, which both are far lower than the requirement. And system has 12Hz bandwidth when 0.4V swept sine wave as input signal. Additionally, the stability, anti-interference and debugging convenience are improved remarkably, compared with former analogue rudder controller.In rudder digital servo controller design, on the software aspect, the common servo controller usually uses the classical position - speed - current three closed-loop control strategy; however, this kind of control strategy has following problems: the implement and tone of the current loop is uneasy, low system track precision and response speed in frequency domain. On concrete control algorithm, the traditional PID control is hard to simultaneously satisfy the system rapidity and low overshoot requirement. Therefore, this dissertation uses a kind of feed-forward-position-speed multiplex control strategy combined with dual-mode fuzzy PID, through the research of servo control strategy and fuzzy control theory,to meets the performance index requirement.On hardware aspect, this dissertation finished control circuit, power driving circuit, as well as signal sampling/converting circuit design. In order to ensure the system precision, this dissertation also developed a special kind of high-precision switching power supply. This kind of fly back switching power supply has high output precision, and peak value of output ripple is less than±20mV, which is only 1/5 of the same level ordinary switch power. Secondly, by hardware anti-interference design and volume control method, high-frequency interference is restrained, system stability is improved and the controller volume is reduced to as much as 3/4 of the former one.Finally, system test results show the feasibility and validity of hardware and software design approach, control strategy and algorithm, given by this dissertation, in missile rudder servo system fulfillment and optimization.更多还原