Functional Characteristics of Excitation Control and Starting System of Reversible Pumped Storage Unit

This chapter focuses on the reversible two‐machine pumped storage unit, which is the most widely used in China. The excitation system adopts the constant excitation current regulation method to directly control the output of the thyristor rectifier bridges in conformity with the start/stop logic control sequence order to achieve field flashing of the generator/motor set, synchronous start under the pump operating conditions, and electric braking at the time of stop. A pumped storage unit plays the role of peak shaver, valley filler, and emergency standby in the grid. Its operation modes include generator operating mode (GO), generator condenser operating mode (GCO), pump motor operating mode (PMO), and pump condenser operating mode (PCO). The unit's start modes include static frequency converter start and synchronous back‐to‐back start. The chapter describes the protection of the shaft current of the pumped storage unit, with Tianhuangping Pumped Storage Power Station as an example.