An abnormal event is referred to an undesired voltage that may happen in power grids. Whenever the event happens, it is necessary to detect it as quickly as possible for consumers' safety. Quickest Change Detection (QCD) can be used to detect the event so as to minimize detection delay, false alarm, and misclassification. The process of how an abnormal event can be detected is described as follows. First, a sensor is deployed to observe the voltage. Then, by using a detection algorithm, the sensor makes a decision according to its observation. Finally, the decision is decoded by using an algorithm at the fusion center. In practice, the post-change distribution could be unknown. By using an algorithm tailored for the condition, the multisensor scenario is verified to have an advantage over the single sensor scenario. Moreover, a coded framework design is proposed, which is shown to improve the decoding performance of the fusion center.

An abnormal event is referred to an undesired voltage that may happen in power grids. Whenever the event happens, it is necessary to detect it as quickly as possible for consumers' safety. Quickest Change Detection (QCD) can be used to detect the event so as to minimize detection delay, false alarm, and misclassification. The process of how an abnormal event can be detected is described as follows. First, a sensor is deployed to observe the voltage. Then, by using a detection algorithm, the sensor makes a decision according to its observation. Finally, the decision is decoded by using an algorithm at the fusion center. In practice, the post-change distribution could be unknown. By using an algorithm tailored for the condition, the multisensor scenario is verified to have an advantage over the single sensor scenario. Moreover, a coded framework design is proposed, which is shown to improve the decoding performance of the fusion center.

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