13,230 research outputs found
Coordinated Control of Energy Storage in Networked Microgrids under Unpredicted Load Demands
In this paper a nonlinear control design for power balancing in networked
microgrids using energy storage devices is presented. Each microgrid is
considered to be interfaced to the distribution feeder though a solid-state
transformer (SST). The internal duty cycle based controllers of each SST
ensures stable regulation of power commands during normal operation. But
problem arises when a sudden change in load or generation occurs in any
microgrid in a completely unpredicted way in between the time instants at which
the SSTs receive their power setpoints. In such a case, the energy storage unit
in that microgrid must produce or absorb the deficit power. The challenge lies
in designing a suitable regulator for this purpose owing to the nonlinearity of
the battery model and its coupling with the nonlinear SST dynamics. We design
an input-output linearization based controller, and show that it guarantees
closed-loop stability via a cascade connection with the SST model. The design
is also extended to the case when multiple SSTs must coordinate their
individual storage controllers to assist a given SST whose storage capacity is
insufficient to serve the unpredicted load. The design is verified using the
IEEE 34-bus distribution system with nine SST-driven microgrids.Comment: 8 pages, 10 figure
Recent advances on recursive filtering and sliding mode design for networked nonlinear stochastic systems: A survey
Copyright © 2013 Jun Hu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Some recent advances on the recursive filtering and sliding mode design problems for nonlinear stochastic systems with network-induced phenomena are surveyed. The network-induced phenomena under consideration mainly include missing measurements, fading measurements, signal quantization, probabilistic sensor delays, sensor saturations, randomly occurring nonlinearities, and randomly occurring uncertainties. With respect to these network-induced phenomena, the developments on filtering and sliding mode design problems are systematically reviewed. In particular, concerning the network-induced phenomena, some recent results on the recursive filtering for time-varying nonlinear stochastic systems and sliding mode design for time-invariant nonlinear stochastic systems are given, respectively. Finally, conclusions are proposed and some potential future research works are pointed out.This work was supported in part by the National Natural Science Foundation of China under Grant nos. 61134009, 61329301, 61333012, 61374127 and 11301118, the Engineering and Physical Sciences Research Council (EPSRC) of the UK under Grant no. GR/S27658/01, the Royal Society of the UK, and the Alexander von Humboldt Foundation of Germany
Output consensus of nonlinear multi-agent systems with unknown control directions
In this paper, we consider an output consensus problem for a general class of
nonlinear multi-agent systems without a prior knowledge of the agents' control
directions. Two distributed Nussbaumtype control laws are proposed to solve the
leaderless and leader-following adaptive consensus for heterogeneous multiple
agents. Examples and simulations are given to verify their effectivenessComment: 10 pages;2 figure
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