Robust Nonlinear Control Design of MMC-HVDC Systems for Wind Power Plants Integration

In the last few years, High Voltage Direct current (HVDC) based Modular Multilevel Converter (MMC) has been heavily used in wind power plants (WPP) integration due to its benefit of independent controllability of active and reactive power. This paper offers a mode switch control strategy for the wind power plant-connected converter. This proposed strategy provides two control modes for the MMC on the WPP side to adjust to various operational conditions. Then, the controllers for the different modes are designed and analyzed using Backstepping and Lyapunov approaches. Finally, in order to validate the performance and effectiveness of the proposed control strategy, we simulate it in a Matlab/Simulink environment.