多绕组变压器具有辐射形等值电路的充分必要条件

The Necessary and Sufficient Conditions of Multi-winding Transformer Generating Radiant Equivalent Circuit

多绕组变压器被广泛应用于电力系统中,但其等值电路往往比较复杂,参数计算难度大,并且难以实现对变压器各绕组的独立控制,在实际应用中给主电路的分析与控制器的设计增加了难度。而辐射形等值电路模型结构清晰简单,便于分析和控制,因此有必要探究多绕组变压器具有辐射形等值电路的条件。将多绕组变压器每一绕组的自感系数和互感系数作为基本参数,从各绕组的正弦稳态电压平衡方程出发,忽略励磁电流的影响,推导出多绕组变压器具有辐射形等值电路的充分必要条件,并以变压器的常用参数——短路阻抗的形式表示。

Multi-winding transformer is widely used in power system. But the equivalent circuit model of multi-winding transformer is always complicated, and its parameter is difficult to compute. It is hard to take independent control of each winding. All above factors make it hard to analyze the main circuit of the system and design the controller. The structure of radiant equivalent circuit model is clear and simple, which makes it easy to analyze and control. So it is necessary to study the conditions in which the multi-winding transformer generates radiant equivalent circuit. Based on the concept of mutual inductance coefficient and self-inductance coefficient, this paper gives the sinusoidal steady-state voltage balance equation of each winding. The radiant equivalent circuit model of multi-winding transformer is derived from the voltage equations by ignoring the effects of exciting current. Finally, this paper presents the necessary and sufficient conditions of radiant equivalent circuit with short-circuit impedance.