An active disturbance rejection control approach for decentralized tracking in interconnected systems

In this article, an Active Disturbance Rejection Control (ADRC) approach is proposed for the robust decentralized solution of local trajectory tracking control problems on the part of agents acting on a complex interconnection of nonlinear subsystems. The key idea is that each agent regards all the nonlinear uncertainties arising from: 1) unknown state dependent nonlinearities of his own subsystem, 2) the environmental exogenous effects and 3) the rest of influences of the network dynamics, as a lumped, unstructured, timevarying uncertainty that perturbs the agent’s subsystem local dynamics. The ADRC approach allows to estimate this complex local interaction function and proceeds to cancel it from each individual subsystem dynamics facilitating the accomplishment of the individual control objectives. Simple but significant illustrative examples are presented where two interconnected DC to DC power converters serve a common or individual uncertain load while trying to independently track a prescribed output voltage reference trajectory in a decentralized manner.