Dynamic protection security assessment, a technique for blackout prevention

In most cases of blackouts, protection systems play a significant role. The maloperation of one protection system can lead to a cascade-tripping of many other protection devices, and so a wide-area interruption of the power grid can affect millions of people. Therefore one important task of a transmission system operator (TSO) is to initiate remedial measures to prevent the grid from such interruptions. The TSO has different tools to operate a secure and reliable transmission grid, e.g. state estimator, dynamic security assessment (DSA) tools and so on. The dynamic protection security assessment (DPSA) is another tool to assess the situation in the grid depending on different contingencies. In addition to the transient network models, protection system models are also included for the simulation of stability problems. In contrast to DSA, DPSA assesses the time-dependent behavior of the protection systems and shows their influence on the grid security.