If a BA's bias setting is -200MW/0.1Hz and NIs changed by +40MW, what is a viable Fs value?

To determine the viable frequency setpoint (Fs) when a balancing authority's (BA) bias setting is given as -200 MW/0.1 Hz and the net imports (NIs) have changed by +40 MW, it's essential to understand the relationship between generation, load, frequency, and the bias setting.

A bias setting indicates how much the BA intends to adjust its generation in response to changes in frequency. In this case, the BA has a negative bias of -200 MW, meaning that a decrease in frequency leads the BA to reduce generation. The unit change of 0.1 Hz per 200 MW suggests a direct proportionality: for every 0.1 Hz that the frequency deviates from a baseline, the BA would adjust generation by 200 MW in the negative direction if frequency decreases.

Changing NIs by +40 MW means that the BA's generation needs to adapt to this import change. The 40 MW increase in imports results in a less negative effect on generation that the BA must make to maintain system balance. To find the corresponding frequency change for the +40 MW import given the bias setting:

1. Calculate the frequency change required to correspond to the +40 MW.

2. Since the BA is operating with