新型固态限流器中饱和型耦合变压器的设计

Design of Saturated Coupling Transformer in a New Bridge-type Solid State Fault Current Limiter

变压器耦合新型固态限流器能够在满足有效限制电网短路电流的前提下,通过合理设计饱和型耦合变压器,达到缩小限流器整体体积、降低成本的目的。文中研究并提出一种变压器耦合新型固态限流器中饱和型耦合变压器的设计方法:首先,在空心电抗器设计的基础上,运用场路结合的有限元法,得出在特定匝数下饱和型耦合变压器的初步设计参数;然后,进一步得出在具有同样限流水平的前提下,饱和型耦合变压器正常运行(副边等效短接)时的漏抗压降,以及故障限流(副边等效开路)时副边电压随铁芯芯柱半径的变化规律,并通过曲线拟合寻优,得到最佳设计。最后,通过小样机实验,验证了该设计方法的正确性。

The transformer coupling novel solid state fault current limiter（SSFCL） could limit the fault current effectively,while its volume and cost could be reduced by probably designing the coupling transformer.A methodology is proposed for designing the saturated coupling transformer in transformer coupling novel SSFCL.Firstly,the scheme for the coupling transformer with winding turns given is acquired,by applying field-circuit coupling finite element analysis（FEA） method and design of the air-core reactor;secondly,based on the premise of the same current limiting level,the change law of the leakage reactance voltage drop in the normal state and the secondary winding voltage in the open-circuit limiting state with the core radius is achieved;finally,the optimal result is obtained by curve fitting and optimization.The validity of the design method proposed is verified by the experiment of the small-scaled prototype.