Power Transformer State Assessment Based on Grey Target Theory

The state assessment of power transformer is the precondition and key to realize power transformer maintenance. The fault system of power transformer can be recognized as a typical grey system. A new method is given to recognize power transformer state without the standard fault model. It introduces grey target theory into state assignment of power transformer. Combining the popular technology of dissolved gases analyses, the arithmetic step for state assessment of power transformer is given. The method uses variable weight to replace equal weight, which is closer to the actual state of power transformer. Variable weight is ascertained by grey target contribution degree technology. The experiment results show it is a new and available method for state assessment of power transformer without the standard fault model, and its validity and efficiency is proved by many examples.