Operational and control approach for PV power plants to provide inertial response and primary frequency control support to power system black-start

Abstract

The renewable generation growth, which includes photovoltaic power plants, has posed challenges for the planning and operation of contemporary power systems. High penetration levels of generation based on fully rated converters makes the black-start of power systems more difficult due to the low equivalent inertia of the system, the performance deterioration of the primary frequency control, the reduced number of black-start units, and the energization of large loads. In the context of the planning and operational challenges imposed by renewable generation, this work proposes an operational and control approach for centralized photovoltaic generation to provide inertial response and primary frequency control support to the black-start of bulk power systems. The proposed control aims to provide inertial response and primary frequency control support only during the system restoration process. The work also proposes an analytical formulation to assess the impact of the operating point of photovoltaic modules on the dynamics of photovoltaic units. The obtained results have shown that photovoltaic power plants are capable of providing support to the black-start of power systems, improving the dynamic and steady-state performance of the system frequency response during the black-start. The performed dynamic analyses have shown that the operational region of the photovoltaic modules significantly affects the dynamics of the power balance in the photovoltaic unit and, consequently, the dynamics of the load pick-up of the photovoltaic modules. The proposed dynamic analysis is useful to support the formulation of control approaches for de-loaded operation of photovoltaic power plants.