Comparison of Frequency Converter Outages: A Case Study on the Swedish TPS System

The purpose of this paper isunavailability of the two main types of conveSwedish traction power supply (TPS) system, i.e.static converter. The number of outages and the ouused to analyze and compare the unavailability oconverters. The mean cumulative function (MCF)analyze the number of outages and the unavailabthe forced outage rate (FOR) concept has been uoutage rates. The study shows that the outagesfailure occur at a constant rate by calendar timconverter stations, while very few stations havedecreasing rate. It has also been found that the stata higher number of outages and a higher outage ratcompared to the rotary converter types. The resultsthat combining the number of outages and the fgives a better view of the converters performasupport for the maintenance decision. In fact, usingdoes not reflect reality. Comparing these two indein identifying the areas where extra resources are maintenance planning and where improvementsoutage in the TPS system.KeywordsFrequency Converter, Forced OuCumulative Function, Traction Power Supply, ESystems.

• Y. A. Mahmood
• A. Ahmadi
• R. Karim
• U. Kumar
• A.K. Verma
• N. Fransson

• Frequency Converter
• Forced Outage Rate
• Mean Cumulative Function
• Traction Power Supply
• Electrified Railway Systems.

[1] A. Pfeiffer, W. Scheidl, M. Eitzmann and E. Larsen. Modern rotary
converters for railway applications. Presented at Railroad Conference,
1997. Proceedings of the 1997 IEEE/ASME Joint. 1997.
[2] L. Shi. Comparison of solid-state frequency converter and rotary
frequency converter in 400Hz power system. 2011.
[3] NES Document TS02, "Requirements on rolling stock in Norway and
Sweden regarding EMC with the electrical infrastructureand
coordination with the power supply and other vehicles," Technical
Specification from the NES Group, 2009.
[4] C. Heising. Modelling of rotary converter in electrical railway traction
power-systems for stability analysis. Electrical Systems for Aircraft,
Railway and Ship Propulsion (ESARS) 2010.
[5] N. Al-Masood, M. N. Sahadat, S. R. Deeba, S. Ahmad, G. A. K.
Biswas, A. U. Elahi and N. M. Zakaria. Reliability evaluation of
Bangladesh power system using cumulant method. Presented at
Electronics Computer Technology (ICECT), 2011 3rd International
Conference On. 2011.
[6] Marko ─îepin, "Reliability and performance indicators of power plants,"
in Assessment of Power System Reliability Methods and Applications,
Springer-Verlag London Limited 2011, Ed. 2011, pp. 197-214.
[7] T. E. Ekstrom. Reliability/availability guarantees of gas turbine and
combined cycle generating units. Industry Applications, IEEE
Transactions On 31(4), pp. 691-707. 1995.
[8] W. Nelson. An application of graphical analysis of repair data.
Qual. Reliab. Eng. Int. 14(1), pp. 49-52. 1998.
[9] W. Nelson. Recurrent Events Data Analysis for Product Repairs,
Disease Recurrences, and Other Applications 2003.
[10] W. Meeker and L. Escobar, Statistical Methods for Reliability Data.
Wiley (New York), 1998.
[11] Liu Fan-mao, Zhu Haiping, Shao Xinyu and Guo Lei. Simple plots for
analysis of the field reliability of horizontal machining centre. Presented
at Intelligent Computation Technology and Automation (ICICTA), 2010
International Conference On. 2010.
[12] A. Z. Al Garni. Graphical techniques for managing field failures of
aircraft systems and components. J. Aircr. 46(2), pp. 608-616. 2009.
[13] S. Niska. Measurements and Analysis of Electromagnetic Interferences
in the Swedish Railway Systems 2008.