考虑高海拔影响的构网型SVG电气回路参数设计OA

The grid-forming converter has voltage source characteristics and has been applied in energy storage,new energy integration systems,and weak systems that require reactive voltage support and transient active inertia support.Based on the grid-forming static var generator(SVG)project configured in the Xizang Nagqu and Ngari regional power grid,this paper proposes the electrical circuit parameter design of the grid-forming SVG in high-altitude areas,determines the selection of insulated gate bipolar transistor(IGBT)devices for SVG,the parameters of modular multilevel converter(MMC)modules,and the value of the supercapacitor as the energy storage component on the DC side.For the overcurrent problem caused by grid faults,the virtual admittance current-limiting and direct current limiting control strategy is applied,ensuring that the converter does not overcurrent.For power grid asymmetry line faults,voltage support and negative sequence voltage suppression strategies are proposed.Through simulation calculations and field tests,it is verified that the parameters of the main circuit components of the grid forming SVG meets the steady-state and transient requirements of the system.In the instant of grid faults,it can provide reactive support and short-term active output for the system,providing reactive and active support for the stable operation of the grid.