Research on Ultrasonic Array Location of two PD Sources in Power Transformer

A new technique to locate the partial discharge (PD) in the transformer is presented in this article, which is based on the extended Multiple Signal Classification Method (MUSIC). The ultrasonic signal of PD is measured directly by the 6 × 6 ultrasonic phased array sensor and the array signal model is formed. The signal from the partial discharge source will be analyzed by the extended MUSIC algorithm. Then space position of PD source is realized by crossover location principle. Thus, one or even several PD sources in the transform can be located. The result of emulator program shows that this algorithm compared with MUSIC has a very high precision and resolution, especially for the sources that are closely positioned. Finally, the result of simulation based on 10 × 10 plane array sensor model vertifies the correctness of the new method.