采用脉宽调制式舵机的滚转导弹自动驾驶仪设计与研究

滚转导弹广泛采用脉宽调制(PWM)模式控制继电式操纵机构，因此研究PWM模式在滚转导弹控制中的应用。给出了两回路驾驶仪设计增益与弹体振荡频率、阻尼之间的关系；重点分析低频PWM所带来的控制耦合效应特性，讨论了耦合大小与弹体时间常数、自旋频率之间的等量关系。通过频谱分析，得到通道耦合干扰的频谱特性。制导与控制指令经PWM后频谱保持不变，但引入了与自旋频率、调制频率和弹体振荡频率相关的高频干扰。为消除控制耦合的影响，根据以上结论，提出这类导弹自动驾驶仪频带设计的一般准则，对这类导弹控制系统的总体设计有参考意义。数学仿真和半实物仿真结果表明，合理设计自旋频率、调制频率和驾驶仪频率，可以有效抑制控制耦合，提高制导精度。

Design and Research of Rolling Missile Autopilot with Pulse Width Modulation Actuator

Pulse width modulation (PWM) actuator system has been widely used for rolling missile. The application of PWM in control system of rolling missile is studied. The relationship between the autopilot gain and the dynamic characteristics of missile, such as oscillation frequency and damping radio, is described, the characteristic of control coupling resulting from low frequency PWM is mainly analyzed, and the relation among coupling strength, spinning frequency and aerodynamic time constant is discussed. The spectral characteristics of disturbance caused by coupling are obtained by spectral analysis. After modulation, the spectra of guidance and control commands for actuator remain unchanged; however, a high-frequency interference is introduced, which is related to spinning frequency, modulation frequency, and oscillation frequency of missile. Finally, the design criteria for autopilot of the missile are proposed based on the above conclusions. The mathematical simulation and Hardware-in-the-loop simulation results show that the application of PWM in rolling missile is feasible, and the design based on the criteria can reduce the effects of control coupling, and also improve the guidance precision.