HybrId Self-adPAtive muLtI-agent systems for microgridS – HISPALIS

Most of power converters can be modelled as switched affine systems with matrices Ai Hurwitz or not. Then, we can use the hybrid representation given through a hybrid dynamical system theory for providing robust and stable systems based on Lyapunov functions. According to the converter topologies, we deal diffeerent problems: regulation, tracking, linear parameter-varying (LPV) systems and energy reduction.

We lead our theoretical research on the robust control of affine switching systems. The first deliverable provides together the main contributions, linked to the hybrid control of systems including a minimum residence time, with switching at constant or variable frequency, in addition to easing the constraint that the subsystems must be Hurwitz, it that is to say stable. This work has already given rise to several publications on the case of hybrid control, considering switching at variable frequencies but with a minimum residence time. Similarly, a robustness study has been published in 2 publications. The objectives of this task have been completed, but we are exploring other theoretical results (initially in discrete time) to improve the performance of this type of system. Indeed, previous research has shown us that it is worth pursuing this path.
We are interested in the themes relating to the applications of hybrid control to DC-DC to AC-DC converters, which is closely related to research concerning previously. We have achieved results on the guarantee of a minimum stay time for the order variable. Hybrid control applications on DC-DC converters have led to publication and on AC-DC converters. Work has started on taking a PWM modulator into account in the closed loop, to conclude on the objectives of this task. Work has also progressed with results published on the robust hybrid control on DC-AC converters, with guarantees of implementation.

Applications to AC-AC converters are going to be studied. Likewise, work on the hybrid control of DC micro-grids in isolated mode has already started. These works are based on the theory of multi-agent systems to guarantee a direct and indirect consensus between the elements, both on the generation side and on the demand side.

Experimental works are expected.

3 journal and 4 conferences papers in renowned journals and conferences in the research field (automatic and electronic) were published in the concerning period.

This project, submitted to the call for proposals entitled ``ANR Jeune Chercheuse, Jeune Chercheur", aims at developing controllers for microtgrids in order to guarantee low distribution losses, high reliability, energy efficiency, robustness with respect to blackouts or parameter changes and scalability. The main objective is to propose new paradigms for the design of several layers of control laws for electronic power systems at the converters and the microgrid levels. First, an intensive attention will be paid to the inner control level for the regulation of the electronic power converters (DC-DC, DC-AC, AC-DC and AC-AC), where the use of the Hybrid Dynamical System theory will be crucial to formulate and exploit the switching control signals in view of reducing the dissipated energy and improving the system lifespam of the devices. Indeed, this recent theory is well suited for analysis of power electronic converters, since they combine continuous (voltage and currents) and discrete (on-off state of switches) signals avoiding, in this way, the use of averaged models. Likewise, an outer control level for controlling the microgrid will be developed to provide a distributed strategy that makes the microgrid scalable and robust with respect to blackouts of sources and/or loads, following the principle of the theory of Multi-Agent System. In this distributed strategy, they are several crucial and innovative aspects to be regarded such as the heterogeneity, the hybrid and nonlinear nature of these converters. The objectives are here to provide robust consensus algorithms in order to take into account the parameter variations. A particular attention on the development of control solutions for DC-bus as well as AC-bus, functioning in islanded mode or grid-connected mode will be paid. Finally, in light of the applicative and experimental nature of the project, a large part of the project will be dedicated to the validation of the proposed theoretical contributions and solutions on the experimental facilities provided by the ADREAM building available at the LAAS-CNRS and the microgrid under construction, MIREDHI-LAB in Colombia.

The project will involve the recruitment of a PhD student and three MS students, to work closely with the four permanent members and one research engineer at LAAS. While the PhD student will l play a main role within project development, the MS students will mostly be involved in some of the application contexts of the project, where strong theoretical skills are not necessary. The project will also serve as an opportunity to strengthen existing collaborations with leading researchers in the field and establish new collaborations, by way of organized visits, seminars and invited sessions in conferences. The results of the research activity will be published in leading journals and conferences in the field of Automatic Control and of Power Electronics.