Basic function to locate and measure the positive peaks in a noisy
data sets. Detects peaks by looking for downward zero-crossings
in the smoothed third derivative that exceed SlopeThreshold
and peak amplitudes that exceed AmpThreshold. Determines,
position, height, and approximate width of each peak by least-squares
curve-fitting the log of top part of the peak with a parabola.
The aip file contains few Matlab routines for 1D line scan analysis, 1D scaling, 2D scaling, image brightness or contrast variation routine and rouitne for finding area between zero cossings of 1D times series.
The growing interest for high data rate wireless communications over the last few decades
gave rise to the emergence of a number of wideband wireless systems. The resulting scarcity
of frequency spectrum has been forcing wireless system designers to develop methods that
will push the spectral efficiency to its limit.
隨著光伏發電系統快速發展,以及電動汽車充電樁的普及,傳統的剩余電流保護器無法滿足實際需求。介紹了一款B型剩余電流保護器,采用磁調制剩余電流互感器和零序電流互感器采集剩余電流。根據GB/T 22794—2017標準要求,可識別1 kHz及以下的正弦交流、帶和不帶直流分量的脈動直流、平滑直流等剩余電流信號。經信號調理電路將電壓信號送到單片機進行采集和判斷。通過試驗測試,該樣機在測試精度和速度上均符合國家標準的相關要求。The rapid development of photovoltaic power generation systems and the popularity of electric vehicle charging piles make the traditional residual current protective devices unable to meet the actual demand.This paper proposed a type B residual current protective device,which uses the magnetically modulated residual current transformer and the zero sequence current transformer to acquire the residual current.According to the requirements of GB/T 22794—2017,the type B residual current protective device can detect sinusoidal AC residual current of 1kHz and below 1kHz,pulsating DC residual current with and without DC component,smooth DC residual current and so on.The signal processing circuit sends the voltage signal to the MCU for acquisition and judgment.Through experimental tests,the device meets the relevant requirements of national standards in terms of test accuracy and speed.
針對交流電路過零檢測電路存在結構復雜、過零點檢測不準確、編程繁瑣等問題，設計了一種基于LM339的硬件結構簡單的過零檢測電路。通過仿真軟件Mulisim對該設計電路進行了仿真，實驗證明了該方案過零檢測的可行性、穩定性和可靠性，可直接作為交流電路中CPU的過零信號。Aiming at the problems of AC cilsuit zero crossing detection circuit such as complex structure, zero crossing detection and cumbersome programming, a zero crossing detection circuit with simple hardware structure based on LM339 was designed. The design circuit was simulated by simulation software Mulisim, and the feasibility, stability and reliability of zero crossing detection were proved by experiments, which can be used as zero crossing signal of CPU in AC circuit directly.
