在綜合分析諧波勵磁無刷同步發(fā)電機勵磁控制系統(tǒng)的基礎(chǔ)上,對其勵磁控制策略進行了研究,開發(fā)了一套基于DSP( TMS320F2812) 控制的新型柴油發(fā)電機勵磁控制系統(tǒng),該系統(tǒng)采用參數(shù)自適應(yīng)模糊PID 控制勵磁,選用交流采樣方式實時檢測各信號的瞬時特性,系統(tǒng)仿真結(jié)果以及在1 臺25 kW 工頻柴油發(fā)電機上的試驗結(jié)果證明了該控制器具有較好的電壓調(diào)節(jié)特性,系統(tǒng)穩(wěn)態(tài)和暫態(tài)性能完全滿足發(fā)電機對勵磁系統(tǒng)的要求。關(guān)鍵詞:勵磁調(diào)節(jié);模糊PID 控制;數(shù)字信號處理器;交流采樣
Abstract :According to the general analysis of the excitation cont rol system of the harmonious wave excitation brushless synchronous generator and it s characteristics ,a new type of diesel generator excitation cont rol system based on DSP( TMS320F2812) was designed. An adaptive fuzzy PID cont rol of excitation is used in this system. To detect the t ransient characteristics of the signals in a timely manner ,AC sampling was applied.The system simulation result s and the testing result s f rom a 25 kW diesel generator (50 Hz) can prove that the voltage regulation characteristics of the excitation cont rol system are very well ,and both the steadyOstate performance and the t ransient performance of the generator are also good.Key words :excitation cont rol ;fuzzy PID cont rol ;digital signal processor (DSP) ;AC sampling
為提升虛擬儀器傳輸速率與實時性能,擴展監(jiān)測范圍,在VC的軟件平臺上設(shè)計了一種全功能虛擬示波器。與傳統(tǒng)虛擬示波器相比,該系統(tǒng)采用嵌入式系統(tǒng)完成信號采集,采用工業(yè)以太網(wǎng)為傳輸介質(zhì),通過線性插值算法和多線程編程思想,實現(xiàn)波形顯示、參數(shù)計算、頻譜分析以及波形存儲及回放功能。實驗結(jié)果表明,該虛擬示波器可以實現(xiàn)20 kHz采樣頻率下的波形精確顯示,達到預(yù)期的各項指標。
Abstract:
o enhance the transfer rate and real-time of virtual instrument performance, expand scope of monitoring, this paper uses the VCs software platform to design a fully functional virtual oscilloscope. Compared with traditional virtual oscilloscope, this system adopts the embedded system to complete the data acquisition, industrial Ethernet as the transmission medium used by the linear interpolation algorithm and multi-threaded programming ideas, namely to achieve waveform display, parameter calculation, spectrum analysis and waveform storage and playback. Experimental results show that the virtual oscilloscope can accurately display the waveform with 20kHz sampling frequency, and achieve the desired targets.
Abstract: High-speed and low-speed data converters serve critical functions in modern broadband mobile radios. This application note outlines how todetermine high-speed data converter performance requirements in baseband sampling radio architectures. Also, system partition strategies andadvantages are outlined when considering a high-speed analog front-end (AFE) solution.
Delta-sigma ADCs, with their high accuracy and high noiseimmunity, are ideal for directly measuring many typesof sensors. Nevertheless, input sampling currents canoverwhelm high source impedances or low-bandwidth,micropower signal conditioning circuits. The LTC®2484family of delta sigma converters solves this problem bybalancing the input currents, thussimplifying or eliminatingthe need for signal conditioning circuits.
在Multisim 10軟件環(huán)境下,設(shè)計一種由運算放大器構(gòu)成的精確可控矩形波信號發(fā)生器,結(jié)合系統(tǒng)電路原理圖重點闡述了各參數(shù)指標的實現(xiàn)與測試方法。通過改變RC電路的電容充、放電路徑和時間常數(shù)實現(xiàn)了占空比和頻率的調(diào)節(jié),通過多路開關(guān)投入不同數(shù)值的電容實現(xiàn)了頻段的調(diào)節(jié),通過電壓取樣和同相放大電路實現(xiàn)了輸出電壓幅值的調(diào)節(jié)并提高了電路的帶負載能力,可作為頻率和幅值可調(diào)的方波信號發(fā)生器。Multisim 10仿真分析及應(yīng)用電路測試結(jié)果表明,電路性能指標達到了設(shè)計要求。
Abstract:
Based on Multisim 10, this paper designed a kind of rectangular-wave signal generator which could be controlled exactly composed of operational amplifier, the key point was how to implement and test the parameter indicators based on the circuit diagram. The duty and the frequency were adjusted by changing the time constant and the way of charging and discharging of the capacitor, the width of frequency was adjusted by using different capacitors provided with multiple switch, the amplitude of output voltage was adjusted by sampling voltage and using in-phase amplifier circuit,the ability of driving loads was raised, the circuit can be used as squarewave signal generator whose frequency and amplitude can be adjusted. The final simulation results of Multisim 10 and the tests of applicable circuit show that the performance indicators of the circuit meets the design requirements.
to show the waveform of audio file and play it on computer
Purpose: Familiar with WAV file format and UI design
It should have the following functions:
Provide a Graphic User Interface for user to browse the file system and select one WAV file
Show the waveform of input audio signal
Play the selected WAV file
Print the parameters of WAV file such as sampling rate, bit-depth, etc
Routine mampres: To obtain amplitude response from h(exp(jw)).
input parameters:
h :n dimensioned complex array. the frequency response is stored
in h(0) to h(n-1).
n :the dimension of h and amp.
fs :sampling frequency (Hz).
iamp:If iamp=0: The Amplitude Res. amp(k)=abs(h(k))
If iamp=1: The Amplitude Res. amp(k)=20.*alog10(abs(h(k))).
output parameters:
amp :n dimensioned real array. the amplitude-frequency response is
stored in amp(0) to amp(n-1).
Note:
this program will generate a data file "filename.dat" .
in chapter 2
Rotating shafts experience a an elliptical motion called whirl. It is important to decompose this motion into a forward and backward whil orbits. The current function makes use of two sensors to generate a bi-directional spectrogram. The method can be extended to any time-frequency distribution
%
% compute the forward/backward Campbell/specgtrogram
%
% INPUT:
% y (n x 2) each column is measured from a different sensor
% ///////
% __
% |s1| y(:,1)
% |__|
% __
% / \ ________|/
% | | | s2 |/ y(:,2)
% \____/ --------|/
%
% Fs sampling frequnecy
%
% OUTPUT:
% B spectrogram/Campbel diagram
% x x-axis coordinate vector (time or Speed)
% y y-axis coordinate vector (frequency [Hz])
In this article, we present an overview of methods for sequential simulation from posterior distributions.
These methods are of particular interest in Bayesian filtering for discrete time dynamic models
that are typically nonlinear and non-Gaussian. A general importance sampling framework is developed
that unifies many of the methods which have been proposed over the last few decades in several
different scientific disciplines. Novel extensions to the existing methods are also proposed.We showin
particular how to incorporate local linearisation methods similar to those which have previously been
employed in the deterministic filtering literature these lead to very effective importance distributions.
Furthermore we describe a method which uses Rao-Blackwellisation in order to take advantage of
the analytic structure present in some important classes of state-space models. In a final section we
develop algorithms for prediction, smoothing and evaluation of the likelihood in dynamic models.