Abstract
The doubly-fed variable-speed pumped storage (DFVSPS) is an effective method to balance the fluctuation of renewable energy generation and is an important means of frequency and voltage regulation of a power grid. Firstly, this paper introduces the structure and mathematical model of the DFVSPS unit. Secondly, the control methods of each switching stage in generating mode and pump mode are proposed, and the simulation study of each stage of DFVSPS switching process is carried out by MATLAB/Simulink. Thirdly, when studying the regulating effect of DFVSPS unit in the power system, due to the high switching frequency of converter in the electromagnetic transient model, the simulation speed is very slow and the data volume is large, so the model of DFVSPS unit needs to be simplified. By analyzing the dynamic behavior of the pumped storage power station, the mathematical model of output power of the DFVSPS unit is established, which includes start-up stage, load ramping stage, stable operation stage, load rejection stage and shutdown stage of generating mode and pump mode. Finally, the simplified model of DFVSPS unit is applied to a simple power system to verify its regulating effect on grid power.
Highlights
Power balance is the foundation of stable operation of a power system, and the frequency and voltage of a power system must be maintained within a certain range to maintain the balance of active power and reactive power
When the doubly-fed variable-speed pumped storage (DFVSPS) unit is running under pump mode, the switching process can be divided into start-up, load ramping, stable operation, load-rejection, and shutdown
Unit able to be applied to power system simulation, the simplified model was applied to the power system simulation, and the following conclusions are drawn
Summary
Power balance is the foundation of stable operation of a power system, and the frequency and voltage of a power system must be maintained within a certain range to maintain the balance of active power and reactive power. The research on the transition process of DFVSPS unit mainly focuses on the performance research of the pump turbine system when the unit is in a bad working condition, such as the sudden power failure of the pump mode and the 100% load rejection of generating mode. [12], the coordinated control of wind turbine and pumped storage unit were studied, and pumped storage unit and photovoltaic power generation system in Refs. The control methods of start-up stage, load ramping stage, stable operation stage, load rejection stage and shutdown on generating mode and pump mode of DFVSPS unit are analyzed in the third part of the paper, and each stage is simulated in MATLAB/Simulink; the converter switching frequency is up to 2–10 kHz, and there will be problems such as slow simulation speed and large amount of data. The simplified power model is applied to a three-machine system to verify the correctness of the conclusion
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
