Study Of Transformer On-line Monitoring Based On Vibration

Power transformer is one of the most important and most used number equipments in the power system, which is also the key components of networking and combining network in power system, so the running status of power transforemer affect the safety of power system. Currently the detection methods about power transformer are mainly off-line detection and on-line monitoring.One-line monitoring of power transformer has become the hot spot and the final trend of transformer detection research, becase it can detects the running status of transformer accurately and real-time under operation.The traditional on-line monitoring system of transformer ( such as partial discharge, transformer oil, etc.) partially focus on the electrical and chemical characteristics, so there are some problems such as without comprehensive monitoring parameters. The on-line monitoring system of transformer based on the vibration method gathers the transformer's vibration signal by the vibration sensor which is installed on the transformer's body, and then the status of the transformer's core and winding is analyzed, by this way the real-time running status of transformer is achieved. The vibration method is a non-electrical monitoring method; it can realize the fault location of transformer, which has impotant significance and good prospect. Therefore, a transformer on-line monitoring system based on vibration method was designed in this article.The main works is as follows:Firstly, the research background of the project is introduced, including the domestic and international developments status of transformer on-line monitoring, and also the objectives and significance of this research topic, and then the relational knowledge of transformer and its common faults are briefly introduced.Secondly, the feasibility of applying vibration method on transformer on-line monitoring is proved. The principle of applying vibration method on transformer on-line monitoring is described in detail from the core vibration and winding vibration. Then the problem in vibration method is also anylized.The core vibration and winding vibration mechanism and characteristic are studied.Thirdly, according the vibration characteristics of transformer, the hardware design and the important components selection of transformer vibration monitoring system based on the PSoC microcontroller and ICP accelerometer are introduced in detail, and hardware anti-interference design is also presented. Forthly, vibration monitoring experiments were done on an actual transformer with the monitoring system. Different failure vibration signals have different characteristics is confirmed by the experiment results, which lays a good foundation for eventually realizing the transformer fault diagnosis.Finally, a preliminary exploration about applying vibration method on monitoring the harmonic current of transformer was presented, including theoretical analysis and experimental analysis.The on-line monitoring system is completed, it will provide a new effective method for transformer on-line monitoring, but there are many problems still need to improve.