Increasing Black Start Capacity by Fast Cut Back Function of Thermal Power Plants

Abstract

Power system restoration is well recognized as one of the most important tasks for electric power grids. During the restoration process, preparation is the first stage, in which time is critical, and many non-blackstart units need to be cranked. The black start capacity plays a key role in preparation stage. This paper addresses thermal units with fast cut back (FCB) function as black start units. The model of FCB unit and algorithm for black start capacity assessment accounting for FCB unit is proposed. First, the general restoration process is briefly introduced. Second, the general restoration process is introduced by summarizing the industrial restoration practice. A piece of software entitled as “System Restoration Navigator” (SRN) is developed and used as a computational tool for restoration strategy assessment. Third, the model of FCB units and algorithm for assessment of FCB function in system restoration are proposed. Fourth, case studies show that FCB units increase black start capacity and reduce restoration time considerably. The proposed method has been successfully applied in Guangdong Power Company, China Southern Power Grid (CSG), where hydro power plants are limited and reliability requirement is critical.