本文選題：頻率域電磁發(fā)射機(jī)　切入點(diǎn)：DDS　出處：《中國地質(zhì)大學(xué)(北京)》2017年碩士論文

【摘要】：井-地電磁勘探是一種有效的金屬礦勘查方法,利用礦區(qū)己有的礦洞與巷道,采用井中發(fā)射、地表接收的方法,能有效地避免地表電磁干擾,增加勘探的精度。相對于傳統(tǒng)的電磁發(fā)射機(jī),本課題設(shè)計(jì)的井-地電磁發(fā)射機(jī),采用了分體式遠(yuǎn)程控制的方案,即將發(fā)射機(jī)的控制模塊與主回路分開,通過多芯屏蔽線纜連接。這種做法有諸多優(yōu)點(diǎn),其中最顯著的是可以避免高壓部分對低壓控制部分的電磁干擾。本文主要介紹井-地電磁發(fā)射機(jī)中的低壓控制部分的硬件電路和軟件設(shè)計(jì)。本文所設(shè)計(jì)的電磁發(fā)射機(jī)主要應(yīng)用CSAMT方法,發(fā)射頻點(diǎn)范圍為1OkHz～0.01Hz。傳統(tǒng)頻率域電磁發(fā)射機(jī)存在頻點(diǎn)覆蓋率低、在野外環(huán)境工作效率不高和同步發(fā)射性能差等問題。根據(jù)課題研制的發(fā)射機(jī)的技術(shù)指標(biāo)要求,本文采用直接數(shù)字頻率合成技術(shù)(DDS)與復(fù)雜可編程邏輯器件(CPLD)設(shè)計(jì)實(shí)現(xiàn)了發(fā)射機(jī)任意頻率的供電波形合成功能;利用CPLD強(qiáng)大的邏輯運(yùn)算能力,在常見的掃頻功能的基礎(chǔ)上增加了一種簡單可靠的多頻發(fā)射波形,提高了野外電磁勘探的工作效率;利用結(jié)合GPS信號的恒溫晶振校準(zhǔn)電路,設(shè)計(jì)實(shí)現(xiàn)了發(fā)射系統(tǒng)的高精度同步發(fā)射。概括而言,控制系統(tǒng)是以ARM+CPLD作為主控,外圍電路主要有DDS、RTC、恒溫晶振校準(zhǔn)電路和無線模塊等。系統(tǒng)中的軟件設(shè)計(jì)主要包括頻率表定時(shí)掃頻程序設(shè)計(jì)、波形合成程序設(shè)計(jì)和發(fā)射脈沖與PPS信號同步程序設(shè)計(jì),其中波形合成程序包含有單頻、多頻和m序列供電波形三種波形的程序設(shè)計(jì)。最后,系統(tǒng)進(jìn)行了多次水槽試驗(yàn)和野外試驗(yàn),其中水槽試驗(yàn)主要進(jìn)行了發(fā)射機(jī)的供電波形測試、同步精度測試和上位機(jī)程序測試等,野外試驗(yàn)則主要測試了發(fā)射機(jī)的整體工作性能。結(jié)果表明,發(fā)射機(jī)合成的發(fā)射波形頻點(diǎn)精度高、頻率穩(wěn)定性好、多頻信號能量分布均勻、發(fā)射同步誤差在納秒級、死區(qū)時(shí)間設(shè)置合理,發(fā)射機(jī)長時(shí)間工作穩(wěn)定,系統(tǒng)可靠性高,完全滿足課題設(shè)計(jì)要求。
[Abstract]:Well-ground electromagnetic exploration is an effective method for the exploration of metal deposits. Using the existing mine holes and roadways in the mining area, adopting the method of in-hole launching and surface receiving, can effectively avoid the surface electromagnetic interference and increase the precision of exploration.Compared with the traditional electromagnetic transmitter, the well to ground electromagnetic transmitter designed in this paper adopts a separate remote control scheme, that is, the control module of the transmitter is separated from the main loop and connected by multi-core shielded cable.This approach has many advantages, the most significant of which is to avoid the electromagnetic interference of the high voltage part to the low voltage control part.This paper mainly introduces the hardware circuit and software design of low voltage control part in well-ground electromagnetic transmitter.The CSAMT method is mainly used in the electromagnetic transmitter designed in this paper. The frequency range of the transmitter is 1 OkHz0. 01 Hz.The traditional frequency domain electromagnetic transmitter has some problems, such as low frequency coverage, low efficiency in field environment and poor synchronous emission performance.According to the technical requirements of the transmitter developed in this paper, direct digital frequency synthesizer (DDS) and complex programmable logic device (CPLDD) are used to design and realize the power waveform synthesis function of the transmitter at any frequency.By using the powerful logic operation ability of CPLD, a simple and reliable multi-frequency transmitting waveform is added on the basis of common frequency-sweeping function, and the work efficiency of field electromagnetic exploration is improved, and the calibrating circuit of constant temperature crystal oscillator combined with GPS signal is used.The high precision synchronous launch of the launch system is designed and realized.To sum up, the control system is based on ARM CPLD. The peripheral circuits include DDS RTC, constant temperature crystal oscillator calibration circuit and wireless module.The software design of the system mainly includes the frequency table timing sweep program, the waveform synthesis program and the synchronous program of transmitting pulse and PPS signal, in which the waveform synthesis program includes single frequency.Program design of multi-frequency and m-sequence power supply waveforms.Finally, the system has carried out many water tank tests and field tests, in which the water tank test mainly carried out the transmitter power supply waveform test, synchronization accuracy test and host computer program testing, etc.Field tests mainly test the overall performance of the transmitter.The results show that the transmitter has the advantages of high frequency accuracy, good frequency stability, uniform energy distribution of the multi-frequency signal, the synchronization error in nanosecond level, reasonable dead-time setting, stable work for a long time, and high reliability of the system.Fully meet the project design requirements.
【學(xué)位授予單位】：中國地質(zhì)大學(xué)(北京)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：P631.325

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 陳光源;鄧明;金勝;王猛;吳承璇;宗芳伊;;井地電磁發(fā)送機(jī)嵌入式人機(jī)交互軟件設(shè)計(jì)[J];地球物理學(xué)進(jìn)展;2016年05期

2 陳凱;魏文博;鄧明;景建恩;王猛;;新一代陸用MT觀測系統(tǒng)[J];物探與化探;2015年04期

3 葛雙超;鄧明;陳凱;;復(fù)電阻率測量方法與模型仿真[J];地球科學(xué)進(jìn)展;2014年11期

4 劉立超;丁凱來;林君;周逢道;劉長勝;;基于偽隨機(jī)系統(tǒng)辨識的電磁法儀器標(biāo)定[J];儀器儀表學(xué)報(bào);2014年08期

5 王旭紅;張一鳴;馮金蘭;韓磊;;大功率電磁發(fā)射機(jī)開關(guān)頻率精確控制研究[J];科學(xué)技術(shù)與工程;2014年20期

6 淳少恒;陳儒軍;耿明會;;偽隨機(jī)m序列及其在電法勘探中的應(yīng)用進(jìn)展[J];地球物理學(xué)進(jìn)展;2014年01期

7 張啟升;鄧明;劉寧;孔銀鴿;關(guān)善亮;;投棄式海流電場剖面儀研制[J];地球物理學(xué)報(bào);2013年11期

8 王猛;張漢泉;伍忠良;盛堰;羅賢虎;景建恩;陳凱;;勘查天然氣水合物資源的海洋可控源電磁發(fā)射系統(tǒng)[J];地球物理學(xué)報(bào);2013年11期

9 陳凱;景建恩;魏文博;盛堰;羅賢虎;陳光源;史心語;;海洋拖曳式水平電偶源數(shù)值模擬與電場接收機(jī)研制[J];地球物理學(xué)報(bào);2013年11期

10 鄧明;魏文博;盛堰;景建恩;何水原;羅賢虎;史心語;;深水大地電磁數(shù)據(jù)采集的若干理論要點(diǎn)與儀器技術(shù)[J];地球物理學(xué)報(bào);2013年11期

相關(guān)碩士學(xué)位論文 前3條

1 茍力;基于FPGA的高速DDS關(guān)鍵技術(shù)研究[D];電子科技大學(xué);2016年

2 馮金蘭;基于DSP&FPGA的地面電磁探測發(fā)射機(jī)的設(shè)計(jì)與研究[D];北京工業(yè)大學(xué);2014年

3 胡思雨;2.4GHz ZigBee與WiFi以及藍(lán)牙系統(tǒng)間干擾分析[D];西安電子科技大學(xué);2014年

，

本文編號：1720249