Research on Control Method of Multi-terminal Flexible DC Transmission System Based on Voltage Droop Control

Abstract

Flexible DC transmission system has the advantages of small line loss, high reliability and strong controllability, and can reduce the frequency of system inactivity. In this paper, the voltage droop control method of flexible DC transmission system is studied in detail. Firstly, the principle and characteristics of the series structure, parallel structure and hybrid structure of multi-terminal flexible DC transmission system are introduced in detail. Based on this, the principle and characteristics of the control strategy of DC voltage droop control of the system are analyzed, and an improved voltage droop control strategy is proposed. Finally, a three-terminal flexible DC transmission system model is built on the Matlab/Simulink platform. The simulation results show that the control strategy plays a certain role in stabilizing DC, AC voltage, AC current and power balance control.