A quantitative evaluation method for power system inertia considering the proportion of multiple resources in operation

With high-proportion new energy grid integration, power system inertia characteristics have evolved fundamentally, and traditional methods relying on synchronous units can hardly meet new-type power system needs. This paper proposes an inertia quantification method based on multi-dimensional inertia resource operation proportion: first, a multi-resource inertia assessment model (covering synchronous units, new energy, DC transmission, flexible loads and energy storage) is built, systematically analyzing various resources’ inertia support mechanisms; second, differentiated quantitative modeling is conducted for each resource’s inertia characteristics to characterize their inertia contribution under different conditions, with an innovative inertia statistical method based on capacity proportion weight proposed for comprehensive assessment of overall inertia; finally, multi-scenario verification is done via PSD-BPA and the proposed frequency response model. In the CSEE small system’s 80 MW load-shedding scenario, the steady-state frequency and maximum frequency deviation errors versus PSD-BPA measured values are only 0.023% and 8.809%.