Control strategy of vibration zone avoidance based on a hydropower-battery hybrid unit

Abstract

As a growing number of renewable energy sources (RESs) are integrated into the power system, how to reduce the wear and tear on units while enhancing the regulating capability becomes one of the most pressing concerns for hydropower plants (HPPs). A hydropower flexibility enhancement innovation technology is studied in this paper, which can provide a real-time control ability to avoid the vibration zones for hydropower units (HUs) by the ‘power sources coordination’ between the HU and the unit-side battery. Firstly, the hydropower-battery hybrid unit (HBHU) model and the zone division of HU and battery are introduced. Secondly, the general principles of hydropower-battery coordinated control are proposed. Based on the state of charge (SOC) management and fast response ability of the battery, a control strategy of vibration zone avoidance for HU is suggested, of which feasibility is verified by the simulation in four typical scenarios. The results show that the coordination of the battery not only helps the HU avoid the vibration zones effectively but also improves the regulation performance, as well as reduces the wear and tear of the unit.