Performance Analysis of Primary Frequency Response in the Indian Power Grid

Frequency control is a fundamental aspect of power systems, acting as a critical indicator of the equilibrium between load and generation. The primary mission of any power system is to ensure that electricity is delivered to consumers at the specified frequency. Frequency variations are chiefly driven by fluctuating demands, shifts in generation sources, and the intermittent nature of renewable energy. To maintain the frequency within a tight tolerance range, two crucial technical parameters come into play: primary frequency response (PFR) and Automatic Generation Control (AGC). It is worth noting that inadequate PFR from generators has been a significant factor contributing to major blackouts over the past decade. Therefore, this paper seeks to assess and analyse the behaviour of frequency during substantial disturbances, focusing on specific metrics that are essential for preserving grid stability. This simple understanding provides the required inputs for the estimation of inertia using the swing equation. Along with the inertia, the performance of the primary response can also be evaluated, and relevant feedback to planners can be given regarding the expected minimum/maximum frequency for any credible contingency.