±800kV特高压直流输电系统主回路参数研究

为制定直流系统的控制策略并提供基本的稳态控制参数,以向家坝—上海±800kV特高压直流输电工程为依托,根据直流输电的基本理论并结合特高压直流系统的特点研究了主回路参数,提出了特高压直流系统的基本控制策略,以及2组12脉动换流器串联(400kV+400kV)构成±800kV特高压的全新换流站接线方案和灵活的运行接线方式。在主回路参数研究和设计中分析了影响主回路参数设计的关键因素,给出了特高压换流站主设备的参数,为特高压直流技术研究提供了基础数据。

Study on Main Circuit Parameters for ±800 kV UHVDC Transmission Project

The calculation of the Ultra-High Voltage Direct Current (UHVDC) main circuit parameters comprises the parameters of the converter transformers, thyristor valves, smoothing reactors, and so on. The main circuit design is very important to the UHVDC Transmission Project, which provides the basis data for the UHVDC system research. According to the forthcoming Xiangjiaba-Shanghai 800 kV(4000A) UHVDC Transmission Project, which adopting the new series (400 kV 400 kV) converter linkage scheme with six type of flexible operation configurations, the report presents a special control strategy used for UHVDC system, analyzes the main factors affecting the main circuit design, and provides the parameters of the primary equipments. The main circuit data include the rating parameters such as rating power, rating voltage, normal current, etc. The primary equipment parameters comprise the rating power, rating current, the operating voltage level, etc. The converter transformer parameters are calculated base on some important factors such as surge on-state current of the converter valve and the reduced voltage operation level. The maximum converter valve stable voltage for design is put forward according to various ideal no-load DC voltage limitations. And the value of the reactor needed on one pole is also brought forward base on the minimum direct current, prevention of commutation failure, DC bias current of the converter transformers and so on. The main circuit data and the primary equipment parameters will be used in the future study of UHVDC transmission system.