Dynamic coupling between power markets and power systems with congestion constraints

Power system markets represented by dynamic equations provide insights into the market behavior, which are not available from static models. A combination of aggressive energy imbalance regulation and fast response of the market can lead to unstable market conditions. Congestion has the potential of substantially altering the market equilibrium point. However, if properly handled, it does not affect market stability. In this paper, the effect of network congestion is studied through the coupling between energy imbalance and markets. The market dynamics is modeled together with the electromechanical power system dynamics. MATLAB-based software is used to evaluate the eigenvalues of a linearized version of an interconnected power system including dynamic market equations. Numerical results are presented to illustrate the effects of congestion constraints on the stability of the system. This paper shows a situation where an unstable market/power system model, is stabilized after congestion is considered