具無效功率量測之電子式數位電表開發

Development of Electronic Power Meters with Reactive Power Measurement

吳國榮(Guo-Jung Wu)

指導教授 ： 蔡孟伸

國立臺北科技大學/機電學院/自動化科技研究所/碩士(2014年)

摘要

目前全球暖化和能源短缺日益嚴重，因此節能減碳的觀念逐漸受到重視，而如何有效使用能源與節省能源，也成為值得討論的議題。要節能減碳必須從日常生活中改變資源使用習慣做起，而首先需要取得這些資源的使用量，才能進行改善。因此，先進讀表基礎建設(Advanced Metering Infrastructure, AMI)在這情況下擔任了重要的角色。而「電子式數位電表」則是建立了「先進電表系統」的核心。
本論文所建構的電子式數位電表開發以MSP430AFE253晶片作為開發平台。此單晶片具有類比數位轉換器不必使用外部前處理電路就可以直接處理電壓訊號與電流訊號。內部有三組二十四位元的Sigma-Delta類比數位轉換器，並附加PGA放大器功能，可以對單相電壓訊號與電流訊號進行同步取樣。單晶片將類比訊號轉換為數位訊號後進行電力參數計算，就可獲得電壓有效值、電流有效值、有效功率、無效功率、視在功率及功率因數。此外，電子式數位電表擁有通訊功能，可透過通訊功能將電力用戶端之用電資料傳回控制中心，並提供電表校正程序，使得電子式數位電表符合誤差標準範圍內。如果電子式數位電表提供了無效功率的資訊，使用者便可改善負載的功率因數，降低線路的損失。因此，本論文利用數位有限脈衝響應濾波器(Finite Impulse Response, FIR)，並透過一階有限脈衝響應濾波器(First-FIR filter)及平移法，完成無效功率的計算。

關鍵字

電子式數位電表 ； MSP430 ； 無效功率 ； 數位有限脈衝響應濾波器

並列摘要

Due to global warming and shortage of energy, the idea of saving energy gradually attracts public’s attention. How to use and save energy efficiently has become an issue worthy of discussion. Therefore, to change the habit of using resources every day, the key is obtain the data usage of these resources first before it can be improved. Advanced Metering Infrastructure (Advanced Metering Infrastructure, AMI) in this case plays a crucial role, and "Intelligent Power meter" is the core to establish "advanced metering system".
This paper utilizes MSP430AFE253 processor as the core element for the development of electronic watt-hour meters. This MCU is specifically designed for single-phase electronic watt-hour meters. It has internal analog front-end circuit that can handle AC signals. The MCU has three 24-bit delta-sigma ADCs that is capable of acquiring single-phase voltages and currents simultaneously and it has an additional PGA (Programmable Gain Amplifier) function. The MCU calculates the necessary information, such as Vrms, Irms, KW, KVAR, KVA, PF, etc. after the signals are acquired. In addition, the development of electronic watt-hour meters have communication capabilities. Such functions help to send the data on electric consumption from users back to control center and meter calibration procedures, making electronic digital meter meets the standard error range. If the Intelligent Power Meters provide reactive power information, users can then improve the power factor of the load, reducing line losses. Therefore, this paper uses digital Finite Impulse Response filter (Finite Impulse Response, FIR), response filter (First-FIR, filter) and the translation method through a first-order finite impulse to complete the reactive power calculations.

並列關鍵字

Advanced Metering Infrastructure ； MSP430 ； Reactive Power ； Finite Impulse Response

參考文獻

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