以嵌入式控制器實作微型相量量測器

Abstract

同步相量量測單元在電力系統中負責將匯流排的電壓及電流訊號計算出其頻率、振幅及相角的設備，且能夠接收衛星訊號，包括時間標籤及每秒一脈衝的訊號，以達到與其他同步相量量測單元同步的功能。同步相量量測單元的資料使用主要分為兩部分，一部分是即時地監測電力系統狀況，若有事故發生時，會在最快的時間內對該事故採取適當的措施且通知操作人員。另一部分為非即時的資料運用，將事故發生時的資料傳送至資料中心，讓相關人員分析事件的成因，以防止相同的事故再次發生或在更短的時間內將問題解決。然而此設備有造價昂貴的缺點，此原因使其自開發成功以來一直難以普遍的使用在電力系統中；且若要建立一個有能力監測整個電網的廣域量測系統，就必須使用低價格且可大量生產以便於在廣域量測系統中佈下為數不少的量測點。本論文的目標即是使用嵌入式系統開發低價格且可大量生產之同步相量量測單元，使其可以在電力系統中廣佈，以增加電力系統的安全度。

Synchronous pahsor measurement units (PMUs) are data acquisition devices utilized in wide-area monitoring systems (WAMS). They are installed at selected buses, sampling three-phase voltage and three-phase current to calculate the phasor. The capability of receiving Global Positioning System (GPS) signals such as time tag and 1- pulse-per-second signal synchronizes phasor data collected from all over the power grid. Synchrophasors in real-time applications are used to monitor the status of the power system so as to, when fault occurs, enable operators to take proper measures as soon as possible. In nonreal-time applications, researchers analyze these data to find the cause of the event in the hope of preventing similar events from reoccurring. Nevertheless, its high price is a significant drawback which impedes its spread. Moreover, when constructing a wide-area monitoring system which monitors the entire power system, devices with easy-to-install characteristic are expected to accelerate the development. And the number of installed measurement units can be even larger. The goal of this research is to develop a mass-producible measurement device which directly samples the voltage from electrical outlets. After some consideration, embedded system with digital signal processor is chosen as the development platform for it performs very well in computing and provides various peripherals.