基于相分量法的新型换流变压器数学模型

The New-Type Converter Transformer’s Mathematical Model Based on Phase-Coordinate

与传统的换流变压器相比,自耦补偿与谐波屏蔽换流变压器具有独特的绕组联结方式。本文以变压器耦合电路原理为基础,以实际变压器设计参数为依据,首次以相分量法建立了反映新型换流变压器绕组联结特点、电气参数等信息的基本数学模型。并结合统一广义双侧消去法,通过对基本模型的拓展,建立了更为详细的计及中性点接地阻抗的节点拓展模型、计及二次角接三角形绕组抽头处滤波装置的支路拓展模型与将抽头处无源设备等效为变压器本体一部分的等效双绕组变压器模型,便于在实际工程中灵活应用。该建模方式合理、简捷、准确,对于解决各种复杂多绕组变压器建模问题具有普遍意义。实际算例表明,所建立的数学模型计算精度高,可用于解决电力系统中与变压器相关的各种实际工程的计算问题。

Compared with the traditional converter transformer, the auto compensator and harmonics shade converter transformer has a unique connection. Based on the transformer coupling circuit principle and the actual transformer design parameter, the three-phase basic mathematical model, which includes the information about the new-type converter transformer＇s wiring feature, the electrical parameters, etc, was presented according to the phase-coordinate method. Through evolution of the basic mathematical model and combination with the uniform generalized double-sided elimination method （GDSEM）, the node continuation model including the earth impedance of the neutral point, the branch continuation model including the filters connected with the secondary comer delta winding＇s tap, and the equivalent two-wing transformer model making the passive devices as the transformer＇s partial body were established in the paper. This kind of modeling way is rational, simple, direct, and has universal significance in solving kinds of the complicated transformer modeling problems. Calculation results show that the calculation precision is high and can be used for solving various actual engineering problems correlated with the transformer in the power system.