A Power Coordination Control Strategy for Wind and Thermal Power Bundling Systems

In light of the uncertainty of active power output from offshore wind farms and the predictability of generation from onshore thermal power plants, this paper proposes a power coordination control strategy suitable for a multi-terminal flexible direct current (DC) transmission system for “wind and thermal bundling.” In the proposed control strategy, the converter station at the thermal power port adjusts the output of the thermal power plant based on whether the change in DC system voltage exceeds preset thresholds, thereby facilitating the reasonable utilization of active power in the multi-terminal flexible DC transmission system. This paper first introduces the multi-terminal flexible DC transmission system after bundling offshore wind power and onshore thermal power. It then provides a detailed design of the proposed control strategy and validates it through a four-terminal flexible DC system constructed in PSCAD/EMTDC. The results confirm that the proposed control strategy can effectively optimize power generation from offshore wind while preventing the converter station at the receiving end from exceeding power limits.