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Hi everyone,

I would like to change the value of loads during dynamic simulation without changing relay shed operations. What I mean is that I would like to modify the actual loads during dynamics without directly modifying the case loads via loadchng4. If you change the loads using this function: loadchng4 it will create a new baseline for relay shed operations. I'll give an example that isn't very practical, but shows the problem rather nicely, if I start at 100 MW on a load and have two shed points via relay setup that shed 10% and 20% respectively I would have 100 MW then 90 MW then 70 MW which is correct. If I'm at 100 MW then shed at point one to get 90 MW and then change the load to 90 MW via the loadchng4 function (I know I'm not actually changing the load value wise, but I am internally changing it in the case memory) and the next load shed occurs it will shed 20% of 90 MW giving me 72 MW. Note I don't want to change the case loadings as it screws up the relay shed points invalidating practical load shedding schemes and making the loadchng4 function inaccurate coupled with protective schemes. An alternative to change loads directly in the dynamics is desired.

Thanks!