The potential for malicious control in a competitive power systems environment

This paper examines the potential for coordinated control of a group of generators in a manner that destabilizes other machines in the system, while maintaining (nearly) completely satisfactory performance within this control group. In particular, this work demonstrates that for an arbitrary group of m control machines, linear feedback control exercised from their frequency measurements to their mechanical power inputs (governor control) can be constructed such that one mode of an otherwise stable, linearized system model is unstable. In the control group, m-1 machines can be guaranteed to show no participation in the unstable mode. As is illustrated by example, the remaining one control machine can display small participation in the unstable mode relative to machines outside the control group. Hence, machines outside the control group might be forced to disconnect from the system first, due to growing oscillations in which they strongly participate. This result indicates the need for careful planning in restructuring utility regulation for a competitive environment, in order to avoid a potentially subtle form of anti-competitive behavior.