Abstract It has already been shown in the literature that power transformers may be more accurately sized by their thermal limits than by their rated power limit. In practice however, thermal limits are usually considered only in operations; but not at planning stage, where the more usual notion of rated power is used. This paper proposes a novel method to take into account (and benefit from) thermal limits directly at planning stage. This is made possible by quantifying separately the impact of each generator and load on the temperature of the distribution transformer. Decoupling the effect of individual generators and loads is achieved by linearizing and rewriting the analytical expression of the hot-spot transformer temperature. The practical value of the method is assessed using a real-world dataset, by estimating the increase in the hosting capacity of the considered transformer for additional generators and loads. Significant gains are obtained when the transformer is sized by generation, in particular when photovoltaic (PV) generators are involved.

中文翻译：

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使用热额定值确定电力系统规划中电力变压器的尺寸

摘要 文献中已经表明，与额定功率限制相比，电力变压器的热限制可以更准确地确定尺寸。然而在实践中，通常只在操作中考虑热限制；但不是在规划阶段，在那里使用更常见的额定功率概念。本文提出了一种在规划阶段直接考虑（并从中受益）热限制的新方法。这是通过分别量化每个发电机和负载对配电变压器温度的影响来实现的。通过对热点变压器温度的分析表达式进行线性化和重写，实现了对单个发电机和负载的影响的去耦。该方法的实用价值是使用真实世界的数据集评估的，通过估计额外发电机和负载所考虑的变压器承载能力的增加。当变压器按发电量确定大小时，尤其是在涉及光伏 (PV) 发电机时，可获得显着收益。