Hybrid Control Strategy for Variable Speed Wind Turbine Power Converters

Abstract

This article employs a hybrid control strategy for variable speed wind turbine power converters. A voltage-controlled voltage source converter algorithm was used in the machine or rotor side of the variable speed wind turbine system. For the grid or stator side of the variable speed wind turbine, a current-controlled voltage source converter method was used. The effectiveness of the hybrid converter system was compared with those using only voltage or current controlled power converters for the variable speed wind turbine in a standard laboratory power simulation package of the Manitoba Research Centre in Canada (PSCAD/EMTDC). It is palpable and discernable from the results that the hybrid control strategy improves the performance of the variable speed wind turbine stability during transient compared to when only the voltage-controlled algorithm was used for the power converters. However, when the current-controlled method is applied for the variable speed wind turbine power converters, the transient stability of the variable speed wind turbine was slightly improved compared to the hybrid converter system.

Keywords

• Voltage-controlled voltage source converter, Current-controlled voltage source converter, Wind energy, Power converter, Transient analysis

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