Gerenciamento e controle distribuído hierárquico primário e secundário aplicado a microrrede CA

Abstract

In the last years, the connection of distributed energy resources (DER) in electric power distribution networks has increased. DER is any resource that generates and storage electricity in a distribution system. An effective way to take advantage of multiple DER benefits is to aggregate them and theirs loads to, under a control structure, form a subsystem called microgrid (MG). A microgrid is able of operating autonomously, as well as connected to the host grid and deal with the transition between these two states. However, MGs introduce operational challenges that need to be approached in the design of the control and protection systems to ensure reliability and an efficient operation. This work proposes a distributed control and management of a MG that operates connected to and disconnected from the power grid, based on the hierarchical control strategy. This approach consists of the segmentation of control at the primary, secondary and tertiary hierarchical levels, enabling the application of faster and slower dynamics according to the process under control. The MG under study is composed by a 40 kVA full convert wind turbine system, a 20 kVA photovoltaic power generation unit, a 30 kVA gas microturbine, a battery bank designed to supply a 15 kW load for three hours and an installed load of 90 kVA. Droop control method was used for primary control and multi-agent system applied in the secondary control level of the MG. The multi-agent system was developed and executed in the Python Agent Development Environment (PADE) platform, in Python language. The MR simulations were performed in the PSCAD software that, in its version 4.6, has a management and control library in Python 3 language, making it possible the interaction of the MR and the multi-agent system in the PADE environment. The simulations were performed considering several operating scenarios of the non-dispatchable sources under light and heavy load conditions. The simulations results atested a suitable performance of the proposed control strategy. The primary control operated precisely in the active power sharing and the secondary control provided good results in the MR resources management. In addition, an adequate performance of the secondary control in the reactive power sharing was verified, reducing the reactive power circulation between REDs.