摘 要:介紹以MP430超低功耗16位單片機(jī)為核心的交流電機(jī)功率因數(shù)測量系統(tǒng),并對該系統(tǒng)的測量原理做了詳細(xì)的說明。在逆變器供電條件下,互感器檢測電機(jī)的線電壓、相電流,經(jīng)信號(hào)調(diào)理電路后,由MP430測量單相電流及電壓之間的相位差,通過計(jì)算求得功率因數(shù)。利用430F449內(nèi)置的定時(shí)器的捕獲功能計(jì)算功率因數(shù),其電路簡單、穩(wěn)定可靠,且測量的精度高。
關(guān)鍵詞:電機(jī);MP430;相位差角;功率因數(shù)
Measurement ystem of Electromotor Power Factor Based on MP430
WANG Xiaolei,WU Birui,JIANG Qun
(Zhongyuan Institute of echnology,Zhengzhou,40007,China)
Abstract:his paper introduces a measurement system of electromotor power factor taking MP430 as a core and gives a detailed explanation to the measurement principle of this systemin condition that the inverter is supplied with power,line voltage and phase current of electromotor measured with transformer after crossing signal conditioning circuit,phase difference of angle between single current and voltage will be measured with MP430 and then the power factor will be get through calculatingWe use the timer of MP430 to measure power factorhis circuit is simple and high-efficiency
Keywords:electromotor;MP430;phase difference of angle;power factor
計(jì)算機(jī)技術(shù),尤其是單片機(jī)技術(shù)和大規(guī)模集成電路及各種新型傳感元件的迅速發(fā)展和日臻成熟,微機(jī)技術(shù)在電力系統(tǒng)中的普及應(yīng)用,使電力系統(tǒng)的測量和監(jiān)控技術(shù)得到了快速的發(fā)展。在工業(yè)生產(chǎn)過程中,往往需要對電動(dòng)機(jī)運(yùn)行期間的功率因數(shù)進(jìn)行檢測,以便采取相應(yīng)的補(bǔ)償措施來提高功率因數(shù),從而達(dá)到節(jié)約電能的目的。若三相負(fù)載不平衡,為能比較真實(shí)地反映三相電機(jī)的功率因數(shù)值,可通過采樣三相交流電中任意一相相電流以及另外兩相線電壓之間的相位差得到三相系統(tǒng)的功率因數(shù)。MP430系列單片機(jī)是一種超低功耗的混合信號(hào)處理器(Mixed ignal Processor),它具有低電壓、超低功耗、強(qiáng)大的處理能力、系統(tǒng)工作穩(wěn)定、豐富的片內(nèi)外設(shè)、方便開發(fā)等優(yōu)點(diǎn),具有很高的性價(jià)比,在工程控制等領(lǐng)域有著極其廣泛的應(yīng)用范圍。使用MP430實(shí)現(xiàn)對電機(jī)功率因數(shù)等電力參數(shù)的測量,不但提高了測量的精度和自動(dòng)化水平,而且降低了系統(tǒng)的功耗[1]。