New paradigmes in control of renewable energy sources for grid voltage and frequency services

Abstract

A new control approach is proposed for the grid insertion of Power Park Modules (PPMs). It allows full participation of these modules to ancillary services. This means that, not only their control have some positive impact on the grid frequency and voltage dynamics, but they can effectively participate to existing primary and secondary control loops together with the classic thermal/inertia synchronous generators and fulfill the same specifications both from the control and contractual points of view.

To achieve such level of performances, a system approach based on an innovatory control model is proposed. The latter control model drops classic hypothesis for separation of voltage and frequency dynamics used till now in order to gather these dynamics into a small size model.

From the system point of view, dynamics are grouped by time-scales of phenomena in the proposed control model. This results in more performant controls in comparison to classic approaches which orient controls to physical actuators (control of grid side converter and of generator side converter). Also, this allows coordination between control of converters and generator or, in case of multimachines specifications, among several PPMs.

From the control synthesis point of view, classic robust approaches are used (like, e.g., $H_{\infty }$ synthesis).

Implementation and validation tests are presented for wind PPMs but the approach holds for any other type of PPM.

These results will be further used to control the units of the new concept of Dynamic Virtual Power Plant introduced in the H2020 POSYTYF project.