智慧電網的目標是發展一個更可靠、安全和適合電網的環境。
不幸的是，電力品質事件容易會因為在智慧電網中不穩定的再生能源而發生。
因此，我們專住在快速偵測多電力品質事件的發生，並且目標在使偵測延遲與偵測錯誤的機率越低越好。在電網中，一群的智慧電表會各別傳送本身的決策到聯合中樞(fusion center)來做最終決策。
此外，有些電表可能是動作不正常的，這些電表會誤導最終決定。
為了對付在有限制頻寬下這些動作不正常的電表，在編碼下的快速偵測已經提出了。
我們貢獻有兩個地方，第一點是透過統計順序定理(stochastic ordering theory)提出的新的局部決策規則，這個方法在傳統存在的矩陣累積和(matrix cumulative sum)有更低的計算複雜度。第二點，在聯合中樞加上編碼方式-
碼書交換與最短距離方法，這個可以使決策錯誤的機率更進一步的降低。

The goal of smart grid is to develop a more reliable,
secure, and environmentally friendly power grid. Unfortunately,
power quality (PQ) events are much easier to happen due to
unstable renewable energy sources in smart grids. We thus focus
on the quickest change detection of multiple PQ events, which
aims to minimize the detection delays and error probabilities of
classifying more than two hypotheses. A group of smart meters
in grid is used, where each meter transmits its local decision to
a fusion center for making final decisions. For energy saving, the
bandwidth between each meter and the fusion center is limited to
be one bit. Moreover, some meters may be faulty and misleading
the finial decision. To combat these faulty meters under limited
bandwidth, a code-based framework for quickest detection is
proposed. Our contribution is two-fold. First, new local decision
rule based on stochastic ordering theory is proposed, which
has lower complexity compared with existing matrix Cumulative
Sums (CUSUM) and completing performance. Second, new fusion
method based on codebook switching and minimum distance rule
is developed, which can significantly lower the error probabilities
compared with existing methods.fold.First,new local decision rule based on stochastic ordering theory is proposed, which has lower complexity compared with exist-
ing matrix Cumulative Sums(CUSUM)and completing performance.Second, new fusion method based on codebook switching and minimum distance rule is developed, which can signicantly lower the error probabilities compared with
existing methods.

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