【摘要】：航空重力測量是一種以飛行器為載體,可以較高效地獲取高精度重力信息的重力測量方法。在捷聯(lián)式航空重力測量系統(tǒng)中所使用的敏感器件激光陀螺以及石英撓性加速度計具有較為明顯的溫度特性,為了保證系統(tǒng)精度就需要對重力儀的熱特性進行研究以提高傳感器的測量精度。本文基于國防科學技術大學自主研制的捷聯(lián)式航空重力測量系統(tǒng),對航空重力測量系統(tǒng)溫度場、溫度控制模型以及方法、溫控下的傳感器數(shù)據(jù)特性以及溫控系統(tǒng)優(yōu)化四個方面進行了研究與分析,主要研究工作歸納如下:1.針對航空重力儀的特點,分析了溫度對于航空重力測量系統(tǒng)的影響。利用有限元仿真工具軟件ANSYS,對系統(tǒng)進行熱分析。根據(jù)外溫控溫度場仿真分析結果以及半導體器件特性,確定了外散熱器選型以及外溫控散熱器整體保溫設計。仿真計算了內溫控系統(tǒng)的穩(wěn)態(tài)以及瞬態(tài)溫度場,確定了內溫控系統(tǒng)測溫點位置、在不同情況下的內外溫控溫度變化關系、內溫控控制能力下限。2.基于熱分析確定了內溫控系統(tǒng)的兩級溫度控制方式,并且利用系統(tǒng)實際數(shù)據(jù)驗證熱分析的正確性。從結構上給出了內溫控加熱片優(yōu)化布置方案以及外溫控強化散熱方案,并且利用仿真實驗驗證加熱片優(yōu)化方案的有效性。3.根據(jù)傳熱基本理論,建立了多級溫度控制的傳熱模型,在定性分析基礎上指出溫控系統(tǒng)設計時應綜合考慮系統(tǒng)熱參數(shù)。對溫控系統(tǒng)進行辨識,得到外溫控系統(tǒng)傳遞函數(shù)模型以及各級設定溫度為輸入天向加速度計比力輸出為輸出的狀態(tài)空間模型。給出PID控制器整定方法,并且研究了時滯系統(tǒng)控制算法。利用辨識結果,利用狀態(tài)反饋的方法對系統(tǒng)進行了控制,抑制了溫度變化對系統(tǒng)的影響。4.詳細分析了航空重力系統(tǒng)溫控系統(tǒng)的數(shù)據(jù),驗證了溫控系統(tǒng)±0.02℃的控制精度。分析研究加入制冷器件后的外溫控系統(tǒng)特性,數(shù)據(jù)表明其能夠保證環(huán)境較大升溫情況下溫控系統(tǒng)精度。分析了精密溫控下慣性器件的輸出特性,研究表明在精密溫控系統(tǒng)正常工作情況下,加速度計的輸出存在較明顯的隨時間的漂移并且其重復性較好,可以利用補償?shù)姆椒ㄏ@一漂移。
[Abstract]:Airborne gravimetry is a kind of gravimetric method which can obtain high precision gravity information efficiently with aircraft as carrier. The sensitive devices used in strapdown airborne gravimetry system laser gyroscope and quartz flexible accelerometer have obvious temperature characteristics. In order to ensure the accuracy of the system, it is necessary to study the thermal characteristics of the gravimeter in order to improve the measuring accuracy of the sensor. Based on the strapdown airborne gravity measurement system developed by the University of National Defense Science and Technology, the temperature field, temperature control model and method of the airborne gravity measurement system are studied in this paper. The characteristics of sensor data under temperature control and the optimization of temperature control system are studied and analyzed. The main research work is summarized as follows: 1. According to the characteristics of airborne gravimeter, the influence of temperature on airborne gravimetric system is analyzed. The finite element simulation software ANSYSis is used for thermal analysis of the system. According to the results of simulation and analysis of temperature field and the characteristics of semiconductor devices, the type selection of external radiator and the whole thermal insulation design of external temperature control radiator are determined. The steady-state and transient temperature fields of the internal temperature control system are simulated and calculated. The position of the temperature measuring point of the internal temperature control system is determined. The relationship between the internal and external temperature control temperature changes under different conditions and the lower limit of the internal temperature control capability are determined. Based on the thermal analysis, the two-stage temperature control mode of the internal temperature control system is determined, and the correctness of the thermal analysis is verified by the actual data of the system. The optimal layout scheme of the inner temperature control heating plate and the external temperature control strengthening heat dissipation scheme are given from the structure, and the effectiveness of the optimization scheme is verified by the simulation experiment. Based on the basic theory of heat transfer, the heat transfer model of multistage temperature control is established. On the basis of qualitative analysis, it is pointed out that the system thermal parameters should be considered comprehensively in the design of temperature control system. By identifying the temperature control system, the transfer function model of the external temperature control system and the state space model with the input temperature as the output of the specific force of the accelerometer are obtained. The tuning method of pid controller is presented, and the control algorithm of time-delay system is studied. Using the identification result and the method of state feedback, the system is controlled, and the influence of temperature change on the system is restrained. The data of temperature control system of airborne gravity system are analyzed in detail, and the control accuracy of temperature control system 鹵0.02 鈩，

本文編號：2133901