微加速度计由于其体积小、测量精度高等优点广泛应用于惯性导航等领域,基于光学测量原理的MOEMS(micro-opto-electro-mechanical system)加速度计不易受电磁干扰,拥有更高的测量精度,具有良好的发展前景。外界环境的变化会对微加速度计的性能产生不利影响,特别是环境温度的变化,高精度微光学加速度计的光腔长度对于温度十分敏感,从而导致探测精度下降,因此提升其温度稳定性势在必行。进行温度控制是降低微光学加速度计芯片热效应的最有效方法,针对所设计的三明治式芯片级封装的MOEMS加速度计,提出了一种基于遗传算法和模糊PID(proportional-integral-derivative)控制的闭环温度控制方案,设计温控电路并使用单片机作为主控芯片,确定被控对象模型后辨识传递函数,同时对系统温度控制参数进行调试整定。文中研究的三明治式微光学加速度计封装结构为温度控制提供了条件,基于模糊逻辑和遗传算法对PID控制参数进行优化的温度控制方案具有良好的控制性能,调节时间快,在理论上使温度控制误差有数量级的减小,有效降低高精度微光学加速度计芯片的热效应。该温度控制方案具有良好的鲁棒性,对其他具有小型半封闭结构的微传感器同样具有实际应用价值。

Micro-accelerometers are widely utilized in fields such as inertial navigation due to their compact size and high measurement accuracy. MOEMS (micro-opto-electro-mechanical system) accelerometers, based on optical measurement principles, offer enhanced measurement accuracy and are less susceptible to electromagnetic interference, making them highly promising for future development. However, external environmental changes, particularly fluctuations in temperature, can adversely affect the performance of micro-accelerometers. High-precision micro-optical accelerometers are especially sensitive to temperature variations due to their optical cavity length, which can lead to a decrease in detection accuracy. Therefore, improving temperature stability is crucial. Temperature control is the most effective method to mitigate the thermal effects on micro-optical accelerometer chips. This paper proposes a closed-loop temperature control scheme based on genetic algorithms and fuzzy PID (proportional-integral-derivative) control for a sandwich-structured chip-level packaged MOEMS accelerometer. The work involves designing a temperature control circuit, with a microcontroller serving as the main control unit, determining the controlled object model, then identifying the transfer function as well as tunning and debugging the system's temperature control parameters. The sandwich-type micro-optical accelerometer packaging structure studied in this paper provides favorable conditions for temperature control. The temperature control scheme with PID control parameters optimizes based on fuzzy logic and genetic algorithms exhibits excellent control performance and shorter regulation time. Theoretically, it significantly reduces the temperature control error by several orders of magnitude, effectively minimizing the thermal effects on high-precision micro-optical accelerometer chips. This temperature control scheme also demonstrates strong robustness, making it practically applicable to other micro-sensors with small, semi-enclosed structures.