Development Of Automatic Control Device For Transformer Vacuum Oil Level

It is important to minimize the risk of grid equipment failures to ensure safe operation of the power grid.This paper looks into possible efficient ways of removing air from transformer oil for enhanced insulating properties.In particular,it discusses how to avoid inter-turn breakdowns given the big potential difference(PD)between the turns of interleaved coil sections.In many cases,the actual oil level of a transformer is difficult to be determined due to its sealed-tank design,where a common practice is to tap the tank on the side and listen to the echoes it produces.To address the issue,the author has invented a new device which fills transformers with oil in vacuum conditions and monitors the oil level automatically.This paper first introduces the composition and status-quo of modern power system,and discusses the major challenges to its safe and steady operation,with a focus on the crucial role of transformers and classification of transformer failures.It further points out that moistened insulation of transformers is a major cause of insulation failures and hence may become an interesting topic to more researchers in the future.After reading a large number of literature and examining current methods of vacuum oil filing,the author is convinced that this research topic is of practical values and great benefits.The paper then elaborates on the theories and uses of transformers,including the basics,performance and function of the equipment.It designs a technical solution of vacuum oil filing;sets out relevant processing,organizational and safety measures;as well as determines the requirements for transformers before oil filing.For its safe,economical and steady operation,the exposure of a transformer to air must be limited and the amount of moisture in transformer oil be minimized during the process of installation and maintenance.On the basis of analyzing the second-order model of the synchronous generator,an active power control structure to imitate the synchronous operation characteristics is proposed.The small-signal model of the active power control loop is built,and the stable operation regions of the PCS are analyzed.Based on this small-signal model,the control parameters of the active-power loop and reactive-power loop are tuned.Finally,the paper introduces the designs of a device that fills oil in a vacuum and monitors the oil level automatically.The device uses a transparent tube to indicate the oil level,an automatic control module to give action signals,and a position switch to trigger different actions and indicate if the oil has reached the predetermined level.From the perspective of frequency regulation and inertia response,control requirements of the energy storage in power system are investigated.The research status of instability issues caused by high-proportion energy storage is summarized,and design requirements of the PCS in this paper are definituded.The development of the device will help ensure safe equipment operation through improved oil filing processes and maintenance results of transformers.The safety of personnel and equipment,which has always been the top priority of the industry,will be better guaranteed with the development of new equipment and innovative solutions.