Research On Static Frequency Start-up Control Strategies For A Pumped Storage Unit

Pumped-storage plant plays an important role of tracking changes in loadreducing peal and filling valley, frequency modulation, phase modulation,emergency reserve etc．in power system. It also has good environmental benefits andgreat potential for development in our country, with the construction of smart gridand new energy development. At present, static frequency converter(SFC) is themain starting mode in pumped-storage plant and of great significance in research,with the function of soft-start, frequent-start, wide speed range etc．Firstly the thesis introduces the topological structure and working principlewhich analysis two commutation method for SCR-Intermittent and naturalcommutation, as well as switching control process of commutation mode. Accordingto the requirements of SFC starting process, the thesis presents the control strategiesfor the variable-frequency starting of pumped·-storage unit, which focuses on rotorposition detection method for the whole process of the motor starter, proposing theposition detection algorithm, such as electromagnetic induction, adaptive fluxregulator, improved phase-locked loop．Next, in accordance with the requirementsof frequency conversion control strategy, a simulation model of the entire startingsystem, including motor modeling and controller design is set up, using Matlab/Simulink．The control strategies of variable frequency starting ale proved to betrue by the simulation platform, which may provide theoretical basis for SFC controlsystem design．Finally, according to the control strategies of the variable-frequencystarting, a SFC control system is designed that PAC is the core supplemented byAPAX-5017data processing circuit. It also gives the design and the realization ofhardware and software．Hardware circuit adopt a modular design method and can bedivided into the controller module, testing and data processing module, triggercircuit module, trigger signal generation module, with the modular method to designthe hardware circuit．In software，according to the control strategies and startingprocess of variable frequency, the software flow diagram and implementation ofSFC control system is provided, as well as the experiment of starting system andanalysis of results.