Grid-Forming Converter DC-link Control considering the Primary Energy Source using a Genetic Algorithm

Abstract

The gradual substitution of conventional synchronous generators by electronic generators raises concerns about the reduction of conventional inertia in electric power systems and the ensuing threat to the stability of those systems. In this regard, grid-forming voltage source converters have been proposed as one of the solutions to tackle this problem. Although a growing body of literature addresses DC-link voltage regulation in grid-forming converters, most existing approaches implicitly assume an ideal and unconstrained DC power source. As a result, the dynamic response and operational limits of the primary energy source (PES)—which can critically shape the available DC side power during transients—are rarely modeled or explicitly accounted for in the design of the DC-link control. With a specific control realization, this paper shows that taking those aspects into consideration from the design stage helps to minimize the possibility of a disconnection of the converter from the power grid when a sudden power imbalance occurs while maximizing the resiliency of the system. The paper provides a systematic methodology to adjust the control parameters. The performance of the proposed control is validated by simulation using a commonly accepted detailed model.

The gradual substitution of conventional synchronous generators by electronic generators raises concerns about the reduction of conventional inertia in electric power systems and the ensuing threat to the stability of those systems. In this regard, grid-forming voltage source converters have been proposed as one of the solutions to tackle this problem. Although a growing body of literature addresses DC-link voltage regulation in grid-forming converters, most existing approaches implicitly assume an ideal and unconstrained DC power source. As a result, the dynamic response and operational limits of the primary energy source (PES)—which can critically shape the available DC side power during transients—are rarely modeled or explicitly accounted for in the design of the DC-link control. With a specific control realization, this paper shows that taking those aspects into consideration from the design stage helps to minimize the possibility of a disconnection of the converter from the power grid when a sudden power imbalance occurs while maximizing the resiliency of the system. The paper provides a systematic methodology to adjust the control parameters. The performance of the proposed control is validated by simulation using a commonly accepted detailed model.