【正文】
od stability. Industrial site often there is a lot of interference factors, thus the digital speed measurement method is widely used in industrial measurement and control system. At present because of its high reliability of PLC has bee an important industrial control equipment, PLC measurement fan and the motor speed can ensure the stability and high precision measurement.Key words: PLC。采用plc測量風(fēng)扇和電機(jī)轉(zhuǎn)速可以保證測量的穩(wěn)定性和高精度。工業(yè)現(xiàn)場往往存在許多的干擾因素,因此工業(yè)測控系統(tǒng)中普遍采用數(shù)字式轉(zhuǎn)速測量方法。另一種是將轉(zhuǎn)速信號轉(zhuǎn)化為脈沖信號,然后用數(shù)字系統(tǒng)內(nèi)部的時鐘來對脈沖信號的頻率進(jìn)行測量。如測速發(fā)電機(jī)是將轉(zhuǎn)速直接轉(zhuǎn)換為電壓信號,然后測量其電壓。目前工業(yè)中測量轉(zhuǎn)速的方式主要有兩種。 題 目 風(fēng)扇性能測試檢測系統(tǒng)設(shè)計 學(xué) 院 工業(yè)制造學(xué)院 專 業(yè) 測控技術(shù)與儀器 2013年 6 月 4 日學(xué)院學(xué)士學(xué)位論文(設(shè)計)風(fēng)扇性能測試檢測系統(tǒng)設(shè)計專 業(yè):測控技術(shù)與儀器摘要:介紹風(fēng)扇性能測試檢測系統(tǒng)設(shè)計方案,對其軟硬件的實現(xiàn)方法進(jìn)行了介紹,該系統(tǒng)在實際工程應(yīng)用中,具有較好的穩(wěn)定性和精度。電機(jī)扇熱風(fēng)扇轉(zhuǎn)速是電動機(jī)重要的基本狀態(tài)參數(shù),在很多運(yùn)動系統(tǒng)的測控中,都需要對風(fēng)扇轉(zhuǎn)速進(jìn)行測量,測量的精度直接決定測試系統(tǒng)的可行性,只有轉(zhuǎn)速的高精度檢測才能得到準(zhǔn)確的風(fēng)扇性能指數(shù)。一種是將轉(zhuǎn)速轉(zhuǎn)化為模擬信號,對模擬信號進(jìn)行測量。這種方法的缺點(diǎn)是被測信號易受電磁干擾和溫度變化的影響。這種方法的優(yōu)點(diǎn)在于抗干擾能力強(qiáng)、不受溫度變化影響、穩(wěn)定性好。目前plc因其高可靠性已經(jīng)成為工業(yè)控制的一個重要設(shè)備。關(guān)鍵詞:PLC;轉(zhuǎn)速測量;穩(wěn)定性;高精度The Design of Fan Performance Testing Detection System Specialty:Measurement and Control Technology and Instrumentation Student Number: Student: Supervisor: Abstract:Fan performance testing detection system design scheme, the hardware and software implementation method are introduced, the system in practical engineering applications, has a good stability and accuracy. Motor heat fan fan speed is an important basic state of motor parameters, in a lot of movement system of measurement and control, need for fan speed measurement, the accuracy of measurement directly decide the feasibility of the test system, can only get the exact fan rotational speed high precision detection performance index. Measuring speed in the industry there are two main ways: one is the rotating speed is converted into analog signals, the analog signal is measured. Such as tachogenerator is speed directly converted to voltage signal, and then measuring the voltage. The disadvantage to this approach is the measured signal is susceptible to electromagnetic interference and the impact of temperature change。 Speed measurement。 Factors。 High precision目 錄緒 論 11. 整體方案 3 設(shè)計方案 3 方案論證與選擇 3 系統(tǒng)工作原理的順序分析 42. 硬件設(shè)置 5 PLC簡介 5 PLC連接 5 傳感器簡介 6 傳感器選型 7 9 人機(jī)界面的設(shè)計原則 103. 軟件設(shè)置 12 放大整形電路 12 I/O分配圖 12 程序?qū)崿F(xiàn) 134. 程序 15 編程軟件 15 程序 155. 結(jié)論 18參考文獻(xiàn): 19致 謝 20I緒 論 1 檢測系統(tǒng)的發(fā)展現(xiàn)狀 測量風(fēng)扇速度的方法很多,但多數(shù)比較復(fù)雜。機(jī)械式主要利用離心力原理,通過一個隨風(fēng)扇轉(zhuǎn)軸轉(zhuǎn)動的閬定質(zhì)量重錘帶動自由軸蕓上下運(yùn)動,根據(jù)不同轉(zhuǎn)速對應(yīng)不同軸位置獲得測量結(jié)果原理簡單直接,不需額外電器設(shè)備,適用于精度要求不高接觸式的轉(zhuǎn)速測量場合。由于受扇葉最小分辨間隔、電路最大計數(shù)頻率等限制,測量精度不能保證。由于受