摘 要
隨著船舶電力系統(tǒng)規(guī)模的日益擴大，各種非線性電力電子設備被廣泛投入到使用，這些設備的使用在提高生產效率的同時，也帶來了一系列的電能質量問題，使得船舶電力系統(tǒng)供電質量惡化。近年來，由于電能質量惡化而引起的各種故障和事故不斷發(fā)生，嚴重威脅到船舶的安全、經濟運行，因此，實時檢測和分析船舶電力系統(tǒng)的電能質量，進而采取有效措施最大限度地抑制其影響，對保障船舶安全運行是非常有必要的。
本文設計了一種基于DSP（數(shù)字信號處理器）的適合用于船舶環(huán)境下的電能質量實時檢測系統(tǒng)，利用DSP芯片強大的計算功能進行多項電能質量指標的在線檢測，實時顯示測量數(shù)據(jù)，為船舶電力系統(tǒng)電能質量的測評提供可靠的依據(jù)。
首先論述了船舶電力系統(tǒng)電能質量問題產生的原因，回顧了國內外在這個領域的研究現(xiàn)狀，簡單介紹了市面上現(xiàn)有的電能質量檢測裝置所存在的問題，接著較為詳細的論述了船舶電能質量的各項指標及其國家標準，從相關標準入手，研究了各種檢測算法并進行仿真分析，然后討論了適用于船舶環(huán)境的檢測系統(tǒng)的軟硬件設計，硬件設計包括有互感電路、濾波電路、信號調理電路、A/D采樣電路、CAN通信接口電路等，軟件設計包括有程序的初始化、A/D采樣程序、數(shù)據(jù)處理算法程序、CAN通信接口程序等?？紤]到船舶電網和陸上電網的不同點，著重加強了系統(tǒng)的抗干擾設計和數(shù)據(jù)通信穩(wěn)定性的設計，最后在船舶電站實驗室進行軟硬件聯(lián)調測試，獲得測試結果。
為了保證測量精度，實現(xiàn)預期功能，本文做了如下關鍵技術的研究：針對諧波檢測，由于船舶電力系統(tǒng)的強噪聲特性使得同步采樣難以實現(xiàn)，而傳統(tǒng)的傅里葉變換(FFT)在非同步采樣下容易出現(xiàn)頻譜泄露和柵欄效應，因此采用加窗插值來修正，即加Blackman-Harris窗函數(shù)來解決頻譜泄露問題，通過雙峰譜線插值來消除柵欄效應帶來的誤差，特別的，針對相位誤差偏大的問題，采用全相位傅里葉變換(APFFT)實現(xiàn)相位零誤差，大大提高了諧波計算的精度。針對電壓波動和閃變的檢測，采用IEC推薦的閃變儀模型，經過反復試驗修正濾波器的參數(shù)，改良后的濾波器檢測精度明顯提高。本系統(tǒng)為了更好的適應船舶工業(yè)環(huán)境，保證實時性要求，采用了高效率與高可靠性的CAN總線作為其通信網絡，很好的實現(xiàn)了下位機和上位機之間的數(shù)據(jù)實時通信。
實驗表明，本電能質量檢測系統(tǒng)具有很高的測量精度，通信穩(wěn)定、可靠，有良好的應用前景。

關鍵詞 船舶電力系統(tǒng)；電能質量；傅里葉變換；加窗插值；全相位傅里葉變換



Abstract
With the continuous development of ships’ power system, various kinds of the nonlinear power electronic devices have been widely put into use. On one hand, they have greatly enhanced the productivity undoubtedly; On the other hand, they have brought in a series of power quality problems, even done great harm to power quality of the applied shipboard power system. By now, many faults and accidents continue to occur caused by the deterioration of the power quality; these problems have already threatened the ships’ safe and economic operation seriously. As a result, to maximize the impact of inhibition, real-time measurement and analysis of the shipboard power quality is very important, and it is essential to the safe operation of the shipboard power system.
The thesis deals mainly with a power quality detection system which based on DSP (Digital Signal Processor) and suited for shipboard environment. With the powerful computing function chip, the system can detect number of power quality indicates online, display real-time measured data. So it can provide accurate proof in testing shipboard power quality.
Firstly, discussed the reasons to causing the problems of power quality in shipboard power system, reviewed the development course in this field by foreign and domestic, and then introduced the existed problems of the power quality test device on the market. Summarized the indicators of shipboard power system’s power quality and its national standards in more detail, from the standards, researched a variety of detection algorithm and simulation. In the following, discussed the software and hardware design which was suited for the shipboard environment, the hardware design includes mutual inductance circuit, filter circuit, signal conditioning circuit, A/D sampling circuit and CAN communication interface circuit. The software design includes the initialization program, A/D sampling program, data processing algorithm program and CAN communication interface program. Taking into account the differences between the ship power grid and land power grid, this system focused on strengthening the anti-jamming design and the data stability transmission design. Finally, overall debugging and acquired the data.
To ensure accuracy and achieve the desired function, this theory made the following key technologies: For the characteristics extra noise of the ship electric power system, it is almost impossible to achieve synchronous sampling, and it is easy to bring in the frequency spectrum leaks and fence effect when traditional FFT algorithm is adopted to analyze in non-synchronous sampling. Aimed at those problems, the thesis used the window function and the interpolation to modify, that is, added the Blackman-Harris window to solve the problem of spectral leakage, and used the double peak of spectral lines interpolation to eliminate the error by the fence effect. Particularly, aimed at the problem of the overlarge phase ..