Research on Synchronous Condenser Configuration Method for Hybrid Cascade UHVDC Transmission System Considering Voltage Instability Risk

The new hybrid cascaded ultra-high voltage direct current transmission system (HC UHVDCTS) exhibits a robust interconnection between AC and DC power transmission. In case of a fault occurring at the load center of the receiving end, there is a possibility of commutation failure and a significant rise in reactive power consumption. Simultaneously, the fault adversely impacts the transient voltage stability of the receiving end grid. Hence, investigating the configuration of condenser in HC UHVDCTS while considering the transient voltage instability risk (TVIR) is crucial for enhancing the safe and stable operation of system. This article first analyzes the topology of the novel HC UHVDCTS and the TVIR mechanism of the multi-feed receiving end system. Subsequently, a transient voltage instability risk indicator (TVIRI) based on multi-binary tables is considered, and a condenser capacitor capacity optimization model for multi-feed DC receiving systems is established based on this indicator. Simulations based on reactive power configuration for transient voltage in multi-feed DC receiving systems are conducted to validate the effectiveness of the proposed method.