Passivity-Based Control for DC-Microgrids with Constant Power Terminals in Island Mode Operation

Abstract

This paper presents a Passivity Based Control (PBC) for a dc microgrid. PBC is commonly used in electrical systems such as power electronics converters and electric machines, but there are few applications in microgrids operating in island mode. PBC is based on properties of passive systems and energy exchange between subsystems. The proposed strategy performs primary and secondary control of the hierarchical architecture. Local communications and measurements are needed at the nodes where dc/dc converters are placed. Simulation studies are performed in MATLAB to validate the control in a realistic test system composed of renewable energies sources, loads and energy storage units. Results show that the proposed control ensures stability and fast response of the dc-bus voltage under different operating conditions. RESUMEN: Este artículo presenta un Control Basado en Pasividad (CBP) de una microrred DC.El CBP se utiliza conmunmente en sistemas eléctricos como convertidores electrónicos de potencia y máquinas eléctricas, pero hay pocas aplicaciones en microrredes que operan en forma aislada. El CBP se fundamenta en las propiedades de los sistemas pasivos y en el intercambio de energía entre subsistemas. La estrategia propuesta desarrolla control primario y secundario de la arquitectura de control jerárquico. Son necesarias comunicaciones locales y mediciones en los nodos donde se ubican convertidores dc/dc. Estudios de simulación son realizados en MATLAB para validar el control en un sistema de prueba real compuesto por fuentes de energía renovables, cargas y unidades de almacenamiento de energía. Los resultados muestran que el control propuesto garantiza estabilidad y rápida respuesta del voltaje del bus dc bajo diferentes condiciones de operación.

Optimal Placement and Sizing of Wind Generators in AC Grids Considering Reactive Power Capability and Wind Speed Curves

“…In this part, we are interested in presenting the tertiary control stage in power system operation, i.e., the optimization stage in hierarchical control structures. The tertiary control stage is also called optimal power flow and it can be implemented as centralized or distributed [31]. This works if links are sent to each active device (e.g., power electronic converters) to provide references to primary and secondary controls [32].…”

A Mixed-Integer Conic Formulation for Optimal Placement and Dimensioning of DGs in DC Distribution Networks

“…Direct current (DC) distribution networks have attracted much attention in recent years in specialized literature [1], since these networks have better voltage profiles [2] and low energy losses [3]. They are easily controllable since frequency or reactive power are nonexistent concepts in these electrical networks [4]. In the literature, multiple approaches regarding DC networks have been described, such as control methodologies for power electronic converters that interface renewable energies [5] and batteries [6], optimization approaches associated with power losses minimization [2] and analysis of convergence algorithms for power flow analysis [7].…”

Stabilization of MT-HVDC grids via passivity-based control and convex optimization

“…The control of an MT-HVDC is similar to a stand-alone DC microgrid which includes a hierarchical control. In [9], a port-Hamiltonian model in conjunction with the interconnection and damping assignment passivity-based control (PBC) was presented for the primary control. In [8], an optimal power flow from a dynamic analysis based on port-Hamiltonian models for controlling power flows in MT-HVDC systems was proposed.…”

“…This method guarantees globally asymptotic stability properties. In comparison with the recent contribution presented in [9], the main advantage of this approach is that our proposed PBC control does not require communication channels in the control step and avoids parametric dependence on the capacitive filter values at each power electronic converter. The approach in [9] required this information to develop its PBC control strategy.…”