  We present a distributed and price-based control approach for frequency
regulation in power grids with nonzero line conductances. Both grid and
controller are modeled as a port-Hamiltonian system, where the grid model
consists of differential as well as algebraic equations. Simulations show that
the resulting controller asymptotically stabilizes the frequency while
maintaining minimum overall generation costs in steady state and being robust
in terms of clock drifts and uncontrollable loads. Moreover, it is shown that
active power sharing can be achieved by an appropriate choice of the cost
function.

Systems and Control;Systems and Control