This talk is partially based on the IEEE Proc.  paper, Nov 2005
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Basic issues with current control
•Primary controllers tuned for the assumed conditions in the rest of the system;
•As system conditions vary,  the controllers could “malfunction” in a variety of ways (ranging from wrong logic, through being too slow  and/or of insufficient capacity; lack of coordination) [2];
•Consequently, hard to ensure system-wide performance;
•Consequently, general tendency  not to rely on control outside normal regions; missed opportunities to operate efficiently.
•A methodology is needed for SEAMLESS management of the system across a  broad range of conditions.