The improvement of the automation level in electricity-heat integrated energy systems (IESs) has laid foundation for the load transfer after contingencies. As the energy coupling core and energy supply source, the energy hub (EH) plays an important role in IESs, where the load of EH’s pipeline segment outlets is defined as operating points. First, the model of security region (SR) is proposed with the consideration of EH’s equipment and pipeline segment N-1 contingencies and the system normal operation. Second, based on the security boundary of SR, the distance from an operating point to a boundary is presented for security assessment. Finally, the effectiveness of the proposed SR model and security assessment method is demonstrated on a test case, which can provide guidance for dispatchers.
Keywords security region, electricity-heat integrated energy systems, energy hub, N-1 security, security assessment