BPA based Selection Method for MMC Reactive Power Control Mode

Modular multilevel converter (MMC) usually adopt direct current control, which can be divided into inner loop current controller and outer loop power controller. The control modes of the outer loop power controller can be divided into active power control and reactive power control. When MMC is connected to AC system, it is necessary to select control mode and control setting values for MMC. This paper proposes a selection method of reactive power control on the basis of analyzing the output characteristics and the influence on AC grids of different control modes along with the reactive power demand of AC grids with different system strength, which is carried out on power system simulation program BPA. The method makes the voltage and reactive power flow regulation demand of AC grid match with MMC output reactive power and voltage. Finally, a simulation model is built on BPA to verify the effectiveness of the proposed method as well as an example of how to carry out this method.