Distributed Collaborative Optimization of Active Power Allocation for MMC-MTDC with Renewable Energy Integration

摘要

Aiming at the frequent power fluctuations of MMC-MTDC system caused by the randomness and fluctuation of renewable energy output, a distributed cooperative optimization control strategy for active power allocation is proposed in this paper. In this control strategy, when the power fluctuation of the system is small and the DC voltage deviation is less than the set value, the unbalanced power is borne by the main converter station to avoid sagging. Frequent adjustment of the coefficients; when the main converter station is not able to bear the power, the converter station using DC voltage sag control can allocate the remaining unbalanced power in proportion to its own capacity. Aiming at the deviation of active power distribution in DC voltage sag control caused by DC line resistance, a distributed cooperative optimization control method is used to optimize the active power distribution. Finally, the PSCAD and Matlab co-simulation platform is used for simulation verification. The proposed strategy improves the accuracy of active power allocation between converter stations and has strong robustness on the basis of ensuring DC voltage stability.