Inertial Support by a Synchronous Power Controlled Type 4 Wind Turbine: A Restructured Control Approach

This paper addresses a key concern about insufficient inertia in future power systems characterized by high penetration of renewable energy sources. In this regard, effective provision of inertial support from a Synchronous Power Controlled (SPC) Type 4 Wind Turbine (WT) is investigated by emulating electrochemical and electrical characteristics of a typical synchronous generator. The kinetic energy possessed by WTs rotary masses is excavated to supply the inertial power offered by SPC solution as the main contribution and hence eliminate the need for installing extra energy storage device. In this regard, a restructured control framework is proposed that the role of dc-link voltage control and maximum power point tracking are assigned to machine and SPC based grid side power converters respectively. Based on Real-Time Digital Simulator results (frequency sweep test), the feasibility of the proposed control framework along with the influence of key control parameters on the dynamic frequency support characteristics are evaluated.