Stability monitoring device and method

A device for controlling production of power in a power system to mitigate a deterioration of transient stability, the device comprising:

• a memory;
• a communication interface;
• and
• a processor that is communicatively coupled to the memory and the communication interface,
• wherein the processor is configured to:
• receive, using the communication interface, fault conditions and a system configuration of the power system;
• calculate an angular velocity and an internal phase angle of a generator in each fault case based on the fault conditions and the system configuration of the power system;
• calculate a severity indicator representing a degree of system instability based on the angular velocity and the internal phase angle of the generator;
• calculate a parallel-off severity indicator for a paralleling off a distributed power supply (PCS power supply) based on a parallel-off sensitivity indicator representing a degree of influence of parallel-off of the PCS power supply on a degree of instability of a generator and the severity indicator,
• extract fault cases corresponding to the parallel-off severity indicator exceeding a prescribed threshold;
• perform a detailed stability calculation for each extracted fault case based on the severity indicator or the parallel-off severity indicator, and
• control the production of the power in the power system to mitigate the deterioration of the transient stability based on the detailed stability calculation for each extracted fault case.