Background:
Vattenfall has a large amount of remote controlled disconnectors used in medium voltage (MV) power distribution systems. At present, disconnector maintenance is mainly based on preventive and scheduled maintenance method. In the coming years, the company will develop, test, evaluate and implement new concepts of digital substation technologies. One aspect among these is to develop techniques of cost effective condition monitoring and condition based maintenance in order to improve quality of power delivery and reduce maintenance costs.
Like other technic system, disconnectors on distribution systems can fail to function. A significant number of disconnector failures are caused by standstill problems. Fail to open or close when required to do so constitutes a major part of disconnector failures. The improper conditions of these operating mechanism failures are very difficult to predict before failure occurs. Thus monitoring of disconnector conditions becomes very important for reliable operation of the power systems.
Condition monitoring can be used to achieve a variety of benefits for power system operation, including prediction of maintenance need, failure prevention, power delivery quality improvement and cost reduction for preventive and scheduled maintenance. It is therefore desired to increase know-how about condition monitoring of disconnectors and study how well the diagnostic method of disconnectors is based on SCADA information, and whether this diagnostic method can meet Vattenfall’s needs.
Objective:
The purpose of this Msc. thesis work is to show if it is feasible to monitor remote controlled distributed MV disconnectors by using SCADA information, that will enable detection of maintenance needs. The focus will be on remote controlled distributed disconnectors in medium voltage (6-33 kV) and it is expected that by performing this Msc. project the following questions could be investigated and answered:
• Is it possible to detect a deviation from a baseline for a specific disconnector by monitoring disconnector operation time from the SCADA system?
• How will external conditions and environment affect the reliability of the condition monitoring method ?
• What are economic benefits, investments and costs expected to arise from effective use of the monitoring method? What will become the overall business benefits for the Vattenfall’s disconnectors concerned?
Qualification, Application and Timeline:
It is preferable that the student has studied Master’s program in Electrical Engineering or Electrical Power Technology or Energy System or Communication and Control of Electric Power Systems.
Your application should contain a covering letter and CV with attach transcripts of your studies. Deadline for application is June 15, 2018. The project is planned to start in September 2018 or according to the agreement made with the student.
Supervisor, Contact person, Location:
The contact person and your supervisor at Vattenfall is Ying He, Tel: 070 58 96960, ying.he@vattenfall.com. The work place will be at Vattenfall R&D in Solna, Arenastaden.
