Transient Performance of Power Systems with Distributed Power-Imbalance Allocation Control
We investigate the sensitivity of the transient performance of power systems controlled by Distributed Power-Imbalance Allocation Control (DPIAC) on the parameters of the control law. We model the disturbances at power loads as Gaussian white noises and measure the transient performance of the frequency deviation and control cost by the H_2 norm. For a power system with a communication network of the same topology as the power network, analysis shows that the transient performance of the frequency can be greatly improved by accelerating the convergence of the frequencies to the nominal value through a singe control gain coefficient. However, the control cost increases linearly as this control gain coefficient increases. Hence, in the feedback control law, DPIAC, there is a trade-off between the frequency deviation and control cost which is determined by this control gain coefficient. By increasing another control gain coefficient, the control cost can be decreased with an accelerated consensus of the marginal costs during the transient phase. Furthermore, the behavior of the state approaches that of a centralized control law when the consensus of the marginal costs is accelerated.