Generic algorithm to calculate Jacobian matrix used for ladder network parameters identification and winding fault diagnosis

• Published in: IET generation, transmission & distribution Vol. 13; no. 15; pp. 3370 - 3377
• Main Authors: Ren, Fuqiang, Ji, Shengchang, Zhu, Lingyu, Zhang, Fan, Liu, Yong
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 06.08.2019
• Subjects: adjoint network method; currents; derivative calculation; double ladder network; fault diagnosis; frequency response; frequency response analysis data; frequency response function; Gauss–Newton iteration algorithm; generic algorithm; iterative methods; Jacobian matrices; Jacobian matrix; ladder network parameters identification; ladder networks; network branch voltages; Newton method; parameter estimation; power transformers; Research Article; transformer windings; winding fault diagnosis; iterative methods; fault diagnosis; winding fault diagnosis; power transformers; frequency response analysis data; frequency response function; double ladder network; Jacobian matrices; transformer windings; currents; Jacobian matrix; generic algorithm; derivative calculation; ladder networks; Gauss–Newton iteration algorithm; parameter estimation; ladder network parameters identification; network branch voltages; adjoint network method; Newton method; frequency response
• ISSN: 1751-8687; 1751-8695
• DOI: 10.1049/iet-gtd.2019.0250

Ladder network parameters identification of transformer winding based on frequency response analysis data is crucial to winding fault diagnosis. In the authors’ previous study, the Gauss–Newton iteration algorithm (GNIA) had been proposed to efficiently identify the network parameters. The core in GNIA is the Jacobian matrix, composed of derivative of frequency response function (FRF) to network components. This study proposes a generic algorithm to calculate this Jacobian matrix. Two key problems concerning the algorithm are solved elaborately. The first problem is the method for derivative calculation toward an arbitrary FRF based on adjoint network method (ANM). The other issue is the mathematical model construction of double ladder network and its adjoint network toward different FRFs to obtain all network branch voltages and currents, which are required in the derivative calculation by ANM. This generic algorithm can efficiently and effectively calculate the Jacobian matrix, which can be applied on ladder network parameters identification and winding fault diagnosis.