Active and Reactive Power Control of Modular Multilevel Converter Using Sliding Mode Controller

The active and reactive power can be controlled and exchanged in a High-Voltage Direct Current (HVDC) transmission system using Modular-Multi level converter (MMC). HVDC based upon MMC improves power exchange capability, transient stability, and power oscillation damping. The challenging task of MMC is controlling its output current, additive currents, internal energy, and sum capacitor voltages. A control design structure for the active and reactive power of modular-multilevel converter is presented in this paper. The output current is decomposed into dq-axis components using park transformation. The dq-axis components are controlled with Sliding Mode Controller (SMC). The SMC has remarkable properties of accuracy, robustness, simple tuning and implementation. The d-axis component is used to control active power and q-axis component is used to control reactive power. Typical MMC is studied and its control is design, simulated and analyzed in MATLAB Simulink.