Audio Monitoring System For Conditions Of Main Equipment Of Substation

With the development of China’s smart grid, most medium and low voltage substation in the country has been achieved unattended. Meanwhile, the communication condition of substation has been greatly improved benefit from the extension of IEC61850. As the core node of grid, substation occupies an important position. In order to ensure the safe and stable operation of substation on unattended conditions, it is necessary to carry out continuous monitoring of its primary equipment. Paper uses the principle of sonic detection method designing a audio monitoring system, which can achieve real-time monitoring for conditions of substation main equipment.Multi-channel audio of equipment can be captured and sent to the audio monitoring host placed in remote centralized control center via Ethernet by the system. The host can determine the conditions of the equipment by analysis the audio data. Paper describes the overall design of the system based on the analysis to actual situation of substation in management model and communication conditions combined with function requirements of the system. Then describe the hardware and software design of the system in detail. In the introduction of hardware design, paper focuses on the design of data collector which uses DSP as the main chip. This part includes component selection and circuit design of each functional module and gives schematic drawn by Protel. At the same, design and installation of audio sensors and selection of monitoring host also be introduced. In the part of software design, paper mainly introduces the software development of communication module and audio data analysis module. This part include the design of driver for Ethernet controller chip RTL8019AS, implementation procedures of embedded TCP/IP protocol stack, extraction procedures for MFCC, which focuses on the selection and embedded achieve of protocol layers for Ethernet communication. The process of Analysis and MFCC’s extraction for the live record audio of transformer are simulated use Matlab by paper as an example, given this process is an important part of audio database training and unusual audio identification. The process of installing and debugging of the system in four substation of Xiamen Electric Power Burean is introduced by the end of the paper.Paper provides a complete design solution for audio monitoring system for conditions of substation main equipment. The system can achieve continuous monitoring for the conditions of an running primary equipment effectively through acquisition and analysis of the audio inside it. Meanwhile, the system also adapt to the management mode of unattended substation and it’s data transmission mode compatible with existing communication networks of substation. In addition, paper finding out characteristics of transformer’s audio and relevant factors of MFCC’s extraction by analysis and extract MFCC for the audio.