以數位訊號控制器為控制核心實現功率因數校正級之設計

DESIGN AND IMPLEMENTATION OF A DSC-BASED CONTROLLER FOR POWER FACTOR CORRECTION STAGE

劉啟宇(Chi-Yu Liou)

指導教授 ： 劉萬榮

國立臺北大學/電機資訊學院/電機工程研究所/碩士(2010年)

摘要

本論文是以全數位可程式化控制概念，設計並實現一應用於低功率之交直流功率因數校正級轉換器。以市電輸入110伏，經自耦變壓器降壓後，輸入到功率因數校正級電路中，輸出一20伏特直流電壓、0.2A~1.2A輸出電流。電源控制核心是以Microchip公司所量產的dsPIC33FJ16GS502晶片，撰寫功率因數校正控制演算法，透過提供平均參考電流幅值，讓電感電流能追隨其信號，期望達到低諧波失真、低漣波電壓與高效率目的。最後，經測試結果，得效率為85%、THD為15.1%、PF為0.9887與輸出電壓漣波210mV。
由於以全數位化控制實現電源系統有可程式化、元件少、設計彈性佳的優點，所以業界也陸續開始進行數位化電源的開發與設計，電路藉由內建周邊ADC，分別偵測輸入電壓、電感電流、輸出電壓並與設定的參考信號做比較後，送至內、外迴路數位PI進行補償，藉由控制法來調整電感電流變化，並經適當調整可得控制PWM的Duty信號，完成循環週期的控制迴路，最後達到輸出穩壓與電流波形追隨輸入電壓波形的目標。同時，論文中將透過Matlab/Simulink軟體，對功率因數校正電路系統的行為與響應進行模擬，作為實作電路各點波形的參考與補償器參數調整的模型。

關鍵字

功率因數校正 ； 數位可程式化控制

並列摘要

This thesis focuses on the study of digitally programmable control concepts, design and implementation of a low power for power factor correction circuit. It used an 110VAC mains voltage as input, then step-down input voltage to the PFC converter by the autotransformer. The output voltage is 20V, and the output current range between 0.2A and 1.2A. Digital Signal Controller as the system control core by using Microchip dsPIC33FJ16GS502. Power system combines software and hardware, which have to write power factor correction control algorithm, then setting the system operates at average current mode. In operating at CCM mode, the input current can achieve low harmonic distortion, low ripple output voltage and high efficiency. Finally, the experimental result shows the efficiency is 85%, THD is 15.1%, PF is 0.9887 and the ripple output voltage is 210mV.
A DSC-based fully digital control of PFC can achieve programmable, fewer components and greater flexibility design. The circuit can be realized through scaling input voltage, inductor current, and output voltage by ADC module. Then compensates and obtains the error signal by comparing the set reference voltage in the digital PI compensation. The signal will send to the DAC to its end, limit to do the steps and control the duty signal for PWM with a complete cycle of the control loop. Finally, the desired output regulation and current in-phase with voltage waveform are achieved. Behavioral simulation of the power factor correction stage is verified by using Matlab/Simulink software and full model of PFC is obtained by reference waveform parameters adjustment and compensation.

並列關鍵字

Power Factor Correction ； Digital Programmable Controlled

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