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Doubly fed induction machine pumped storage system: Laboratory set-up and grid synchronization

Variable speed pumped storage system is gaining more importance in order to improve power-grid quality and control. The doubly-fed induction machines based variable speed systems, are the most appropriate systems due to their optimized converters size. Despite the advantages that this structure provides for renewable energy integration, most existing installations are based on fixed speed using synchronous machines. In this paper, authors propose a laboratory set-up using another structure. The different working phases of variable speed pumped storage systems using doubly fed induction machine are tackled by providing an efficient control algorithm. The real experimental tests are achieved using a 4kW laboratory set-up to validate some elementary control modules required for the each working phase algorithm in the first step. In the second step, the stator connection test with the grid is performed. Thus, one of the working phases is validated. Simulation results of the proposed algorithm shows the robustness of the synchronization strategy mainly in the case of grid faults.