離網電力電子解決方案，太陽能供電的應用

　　隨著安裝光伏太陽能的成本急劇下降，該技術正日益成為支持非并網應用的現實解決方案。國家可再生能源實驗室（NREL）計算太陽能系統的安裝成本在2010到略高于7美元/瓦，與Solarbuzz顯示系統定價15.50美元每千瓦小時趨勢。這是整個系統，包括太陽能電池，儲能裝置，以及充電器和逆變器的電力電子。

　　從便攜式、公路建筑標志和閃光指示器到遠程抽水站和通訊網絡，非并網應用的機會似乎無窮無盡。價格的下降繼續降低了進入市場的重大障礙，使得曾經嚴重成本高昂的項目成為現實。

　　我們將專注于電力電子系統和一些關鍵的機會和權衡時，要記住設計非并網太陽能系統。與解決大多數系統級問題一樣，從最終應用程序需求開始，向后工作以識別、定義和調整整個系統通常是最容易的。

　　The load

　　The load could be virtually anything， but an off-grid application is off-grid for a reason. The application may need to be portable， as is the case with construction information signs or simple hazard flashers. Given their portability， it is clearly not feasible to run a grid connection for each. Or perhaps the application is in a remote location， such as may be the case with a cellular communication tower or a remote pumping station.

　　Let us start by identifying some of the key items to consider when developing an off-grid， solar-powered solution. Figure 1 provides a high-level system block diagram. Using an energy-balance approach， the key is to understand the load， including its type and behavior over time.