Research on Multi-Mode Control Strategy of Distributed Static Synchronous Series Compensator

With the development of new energy grid-connected scale and load diversification, the new power system is faced with the problems of uneven power flow distribution, three-phase unbalance aggravation and line current over-limit. At present, the mainstream solution is to adopt the centralized flexible AC transmission technology which is relatively mature but has poor flexibility and economy. However, due to its own defects, it is difficult to adapt to the dynamic development of the new power system with changeable operation modes and occasions. Therefore, this paper proposes to adopt a distributed static synchronous series compensator with good economy and simple structure to adjust the line power flow, regulate the line current and compensate the line impedance, so as to realize the safe and stable operation of the power grid. In this paper, the topology of DSSC is analyzed, the mathematical model of DSSC is constructed, and the control strategy of DSSC working in multi-mode of power flow regulation, current limit and impedance compensation is proposed. Based on ADPSS, the electromagnetic transient model of 110kV power grid in Guangshui county is constructed, and the effectiveness of the proposed control strategy is verified.