The penetration of non-synchronous renewables and the abandonment of conventional power plants are bringing a number of power-system-related challenges such as: reduction of total system inertia; increasing rates of change of frequency (RoCoF); reduced frequency and angular stability and a decreasing number of generation units providing frequency regulation. The drop of the system inertia level has become a widely acknowledged issue, which can lead to a faster fall in frequency for the same power imbalance and may result in suboptimal operation of the traditional under-frequency load shedding (UFLS), causing an additional negative effect on system resilience. A novel, synchronous-condensers’-power-injection-based UFLS method is proposed by the authors. The preliminary test case and estimation has shown that the proposed rapid load shedding (RLS) approach significantly improves the post-contingency frequency response when compared with the traditional UFLS scheme. At present, a hardware platform, the operation algorithm and innovative scheme of the RLS system terminals are being tested in laboratory. The preliminary results have shown the advantages of the proposed innovative scheme of PS emergency control. Its implementation provides the opportunity to soften the restrictions regarding the selection of the maximum allowable capacity of synchronous generators and transmission network interconnections in the pre-emergency mode. Based on the usage of PS dynamic models and the NORDPOOL electricity market model, a methodology for assessing the economic benefit of applying the proposed solution has been developed. The case study of the Baltic power system (incl. analysis of power system operation modes) demonstrates the possibility of obtaining a positive economic effect due to optimal use of the capacities of the transmission network interconnections and economically efficient generation.