Back-to-back Converter Control of Grid-connected Wind Turbine to Mitigate Voltage Drop Caused by Faults

Power electronic converters enable wind turbines, operating at variable speed, to generate electricity more efficiently. Among variable speed operating turbine generators, permanent magnetic synchronous generator (PMSG) has got more attentions due to low cost and maintenance requirements. In addition, the converter in a wind turbine with PMSG decouples the turbine from the power grid, which favors them for grid codes. In this paper, the performance of back-to-back (B2B) converter control of a wind turbine system with PMSG is investigated on a faulty grid. The switching strategy of the grid side converter is designed to improve voltage drop caused by the fault in the grid while the maximum available active power of wind turbine system is injected to the grid and the DC link voltage in the converter is regulated. The methodology of the converter control is elaborated in details and its performance on a sample faulty grid is assessed through simulation

Stability Analysis and Optimal State Feedback Control of Back-to- Back Converter

Developing of transmission systems and using of different energy sources to supply the demand of network power makes that the using of power electronic converters are increased. Among the power electronic converters, Back to Back (B2B) converters are operated in the power system today's widely. These converters can be located in connection of distributed power generation systems to power network and in HVDC transmission systems. In this paper stability analysis and controllability of B2B converters based on the average model in HVDC power transmission systems is studied. Also, optimal state feedback control under different conditions for B2B converter is proposed. Finally, simulation results are illustrated in order to verify the capability of proposed control strategy