Voltage Differential Control of Multi-terminal DC Distribution Network Based on Active Power Balance

With the rise of renewable energy and the development of power electronics, the DC distribution network will play an increasingly important role. Firstly, this paper described the typical topology and operation mode of multi- terminal flexible DC distribution network. Secondly, in order to solve the problems of voltage control deviation and strong communication dependence in the traditional control strategy of multi-terminal flexible DC distribution network, an adaptive voltage differential control (AVDC) was proposed, which enabled the converter stations to adjust voltage and maintain power balance instead of the master station. By detecting the bus voltage signal, the converter station can switch mode independent of the communication system. Finally, a simulation model was built based on PSCAD / EMTDC platform, and the effectiveness and superiority of the proposed control strategy were verified by simulating the master station exit and load removal conditions.