Master Thesis project: Subtransmission reliability study using PSS/E

Background, purpose: Vattenfall Distribution builds substations in their 70 and 130 kV meshed subtransmission network. The layout of the switchgear in these substations has an impact on the security of supply of electricity to the customers.

The purpose of the project is to identify the financial and technical consequences in different layouts and to suggest an appropriate strategy for Vattenfall Distribution on reconstructing existing substations.

Master Thesis project: The thesis is mainly divided into 3 parts as follows.
• Network modelling in PSS/E
A subset of the existing subtransmission network will be used for the project. This subset needs to be taken out from the complete network model. The network subset needs also to be added with substation layout and switchgears since this is not included in the model today.
• Reliability analysis in PSS/E
For each of the substations in the studied network the probability for loss of supply shall be calculated. This probability shall also be calculated for different substation layouts and compared from reliability and a financial aspect. On component level (e.g. breaker, disconnector) different types of configuration will be studied.
• Recommendation
The overall results shall answer where in the studied network will reliability improvements be most cost efficient, i.e. a priority list.

Vattenfall Distribution will provide introduction and guidance in PSS/E. Vattenfall will provide statistics on and cost of components and transmission lines and costs of outages.


Master Thesis Report and presentation: The report shall be written in English. Presentations will be given both at Vattenfall and at the home University. Revision of the report shall be based on comments during presentations.

Student education requirements: The student shall have fulfilled all courses on a relevant University program. Suitable program/courses could be power system and reliability. The student shall write and speak English.


Time schedule: The project shall preferably be started as soon as possible but if more suitable the start can be delayed. The project prolongs during the mandatory period of 20 weeks.


Supervision: Ying He and Daniel Wall, Vattenfall R&D, and Johan Öckermann, Vattenfall Distribution, will supervise the project. The project will be conducted in the Vattenfall R&D office in Råcksta located west from Stockholm City and in Vattenfall Distribution office in Sundbyberg.


Contact person:
Daniel Wall, Vattenfall R&D +46 8 739 72 54
[email protected]

Application shall contain records of academical achievements and a personal letter. Deadline for applying is 2010-12-10.