Many operations in power grids, such as fault detection and event location estimation, depend on precise timing information. In this paper, a novel time stamp attack (TSA) is identified in smart grid. Since many applications in smart grid utilize synchronous measurements and most of the measurement devices are equipped with global positioning system (GPS) for precise timing, it is highly probable to attack the measurement system by spoofing the GPS. The effectiveness of TSA is demonstrated by time synchronized transmission line fault detection, as well as regional disturbing event location. To defend against TSA, we proposed a multi-antenna based quickest GPS spoofing detection algorithm. By exploiting the theory of quickest detection, we apply the probabilistic metric of the carrier signal to noise ratio from two receive antennas to conduct the quickest GPS spoofing detection. Experiment results demonstrate that the proposed defense scheme can effectively detect and prevent GPS spoofing attack.
展开▼
