View of TECHNO- ECONOMIC ANALYSIS OF USEFUL LIFE OF TRANSFORMERS WITH SPECIFIC PARAMETERS : REVIEW

(1)

ACCENT JOURNAL OF ECONOMICS ECOLOGY & ENGINEERING Available Online: www.ajeee.co.in/index.php/AJEEE

Vol.02 , Issue 02, February 2017 , ISSN -2456-1037 (INTERNATIONAL JOURNAL) UGC APPROVED NO. 48767

1

TECHNO- ECONOMIC ANALYSIS OF USEFUL LIFE OF TRANSFORMERS WITH SPECIFIC PARAMETERS : REVIEW

1SHALINI VAISHYA,

Research Scholar Electrical Engineering

2PROF. DR. S.R. NIGAM,

3PROF. DR. SMITA SHRIVASTAVA

123AISECT University Bhopal , Madhya Pradesh, India

Abstract:-Keeping in mind the end goal to make the transformer Insulation aging assessment appraisal and life expectation more sensible, we will try to simulate a MTALAB / Simulink model for insulation life transformer assessment display in light of the working burden, ecological factors, the electrical qualities of the trial and oil chromatographic attributes for techno economic evaluation of the transformer. I reviewed number of research articles for the proposed work.

Index Terms— Techno Economic, Transformers, Intelligent System, Review.

1. INTRODUCTION

Power transformer not only shoulders on the responsibility of supply load, it’s safe and stable operation is the urgent need to protect [1]. Therefore, key technology and comprehensive preventive measures for transformer fault detection research and application[2], reduce the damage rate and fault tripping rate is meaningful. At present, domestic and abroad proposed the concept of "life-cycle management" for transformer , to predict its operation risk and reliability[3], thus combining economic management to make effective maintenance and replacement strategy[4], which is the development trend of the current electric power industry. Therefore, grasp the causes of aging and the development of the underlying causes, as a theoretical guidance for the aging state effectively assess[5], reduce accidents and improve transformer especially safe operation of more than 20 years of operation of the transformer[6], the transformer scientific prolong the life of a very important practical significance.

1.1 TRANSFORMER INSULATION CONDITION ASSESSMENT MODEL Transformers are very important elements to electric networks, both for the operational utility and for the cost. When in operation, they are exposed to different operational conditions, such as overload, harmonics, undue heats, and mechanical vibrations among others that may cause degradations in their operational and insulating conditions. However, a predictive maintenance system is desirable so that the mechanic, insulating and electrical conditions are determined, avoiding turn-offs and incorrect

operations. This system can also help in the elaboration of planning, maintenance and decision-taking regarding the widening of the system. For example, when the active part of the transformers is immersed in insulating oil, the heat caused by the electric efforts alters the composition of the insulating oil causing the liberation of several gases, depending on the temperature reached and the place of the heated active part. The gas chromatography test quantifies and determines the dissolved gases in the oil from small samples. Interpreting the results. obtained in the gas- chromatography test takes to the finding of the transformer’s working conditions. A transformer’s predictive maintenance system requires that several measures shall be performed in many elements, such as: quality of the insulation, deterioration of the insulating paper, current state of the oil, existing gases, noise, temperature, measurements in many points, among others [1].Therefore, for the correct evaluation of all data, it is necessary to establish a supervising system of those parameters.

1.2 MOTIVATION

No research reported in the literature that covers the physical or economic assessment of transformer lifetime, taking into consideration the effects on the end of life decision of the surrounding networks or the loads served by the transformer. In the techno-economic technique developed in this study, the effect of the surrounding network was taken into consideration as follows:

(2)

2 a. The cost of interruption caused by

transformer failure.

b. The type of the load served by the transformer.

Studies related to a transformer health index or health condition are rare, and most need modification. Many require review of the importance allocated to the parameters measured, include more measurements of additional parameters, and others should use real measurements.

1.3. PRESENTATION OF THE PROBLEM The evaluation of the transformer’s service life, based on all information evaluated and on the adequate manipulation of that information, is a task belonging to the information processing systems associated with the technical knowledge stored in the expertise of the company’s staff. Once the extracted information from the monitored variables is available, it shall feed a sufficiently consistent model that can present a trustworthy evaluation regarding the loss of service life of the transformer under supervision. The model to obtain such evaluation shall be established with base on two paradigms.

In proposed research I will try for the consideration of techno economic consideration in the term of Insulation and other parameters for the improving the life performance of the Power transformer with using the technique with MATLAB/Simulink software. In our proposed work above mentioned issues will be incorporated to develop a globally optimal decision support system for replacement of existing transformer with new transformer.

2. LITERATURE REVIEW

R. Batruni, et.al described by well-known that cellulose materials used to insulate transformer windings gradually degrade during service due to a combination of thermal, mechanical, and electrical stresses. As a result the mechanical characteristics of the paper change during use and may aflect the useful life of the transformer. It has generally been assumed that the electrical characteristics remain relatively constant throughout the aging process. If, however, thermal aging changes the electrical characteristics, it may be possible to gauge the thermal age of a transformer by

externally monitoring these electrical characteristics over time.

Ken Chen, et.al described that Sunohio PCBX process, a chemical destruction process, was closely examined for its use in removing PCBs from and in reclaiming PCB-contaminated mineral oils for reuse.

The PCBX process effectively removed PCBs from a concentration of 1100ppm to. 2ppm or less; however, improvement of the oil quality from the untreated to the treated state was not statistically significant. Most of the treated oil qualities were satisfactory in physical and chemical properties; however, some of the treated oil qualities were not acceptable in electrical properties.

Wang Wei, et.al shows that Single-phase distribution approach is one of new low- voltage power distribution technologies. It is significant for reducing distribution line losses, improving power supply reliability and assuring voltage quality. RMS current method is adapted in this paper. In a typical residential community, distribution transformer loss, low voltage line loss and investment in equipment single-phase and three-phase distribution methods is calculated, compared and analyzed.

Ahmed E. B. Abu-Elanien, et.al described that method for developing a more systematic approach to determining the replacement time of transformers is presented. The approach is based on an economic analysis of transformers in conjunction with the technical issues involved in the decision process.

Enhanced use is made of the well-known bathtub failure model, including repairs and scheduled maintenance, in order to arrive at a more economically oriented replacement decision.

Sven C, et.al proposed that (N-1)-security is a decisive impact factor on both transmission system operation and network planning as it constrains the permissible states of the grid. Ensuring an (N-1)-secure operation and planning is a particular challenge in the presence of uncertainties. The inefficiency due to constrained network operation can be alleviated by fast corrective actions, e.g.

by FACTS devices, HVDC or phase shifting transformers: a corrective (N-1)-

(3)

3 security analysis accounts for fast reactions to post-contingency situations.

In this paper, first an approach for a techno-economic analysis will be presented that allows for the evaluation of corrective controls in system operation.

T. Stetz, et.al described that first, we investigate the technical and economic potential of autonomously operating voltage control strategies in low voltage grids with high photovoltaic penetration.

The investigated control strategies are based on the reactive power control capabilities of modern photovoltaic inverters and the application of distribution transformers with on-load tap changers.

3. COST-BENEFIT ANALYSIS

The extent of necessary grid reinforcement measures can be estimated by applying the assessment approach as introduced in Section II. However, by changing the grid configuration (e.g.,laying of additional cables, exchange of transformer) certain operational costs of a DSO are directly affected (i.e., costs for network losses, compensation of PV plant operator for lost energy feed-in, reactive power compensation). It is therefore required to include these costs in the cost-benefit analysis as well. This Section presents a methodology for such a cost-benefit analysis and discusses the results for the autonomous VCS, which were introduced in Section II. The cost- benefit analysis is conducted in three consecutive steps: In the first step, a PV expansion scenario is defined for the investigated LV grid, covering a time frame of 10 years. In the second step, the extent of necessary grid reinforcements is defined for each year, considering the leveraging effect of each of the VCS.

Finally, one year RMS simulations are performed in order to assess the operational costs for each year and each VCS. Limiting the investigated time span to 10 years seems justified, as external effects (e.g., changes in regulatory frame, novel technologies etc.) can impair the significance of such an analysis.

4. CONCLUSION

The services of maintenance directly interfere in the quality sand continuity of the electric energy supply. A well done maintenance avoids untimely turn-offs

and postpones the service life of the transformer. For a well done maintenance, it shall start with a correct report, which points out the possible flaws (or future flaws) in a clear way. The expected product from this project was the development of a methodology for the analysis of data for the transformer maintenance system. A new method for determining the life expectancy of transformers will proposed with MATLAB/Simulink software for the power transformer. This method has the advantage of being based on both economic constraints and the technical parameters of the transformer.

REFERENCES

1. R. Batruni, R.C. Degeneff, M.A. Lebow,

“Determining The Effect Of Thermal Loading On The Remaining Useful Life Of A Power Transformer From Its Impedance Versus Frequency Characteristic, IEEE Transactions on Power Delivery, Vol. 11, No. 3, 1996 2. Ken Chen, “Evaluation Of The SunohioPcbx

Process For Reclamation Of Transformer Oils Containing Pcbs”, Ieee Transactions On Power Apparatus And Systems, Vol. Pas-102, No. 12, 1983

3. Ahmed E. B. Abu-Elanien, M. M. A. Salama, Fellow, Ray Bartnikas,” A Techno-Economic Method For Replacing Transformers” Ieee Transactions On Power Delivery, Vol. 26, No.

2, 2011, 0885-8977

4. Wang Wei, XuLijie,XiaoWanjun, Wang Yingnan,ZhaoQingqi, Qi Weifu , RenZhe,

“Technology Research and Techno-economic Analysis on Single-phase Power Supply Mode in Distribution Network”, CICED, 2010 5. Ahmed E. B. Abu-Elanien, M. M. A. Salama,

R. Bartnikas, “A New Techno-Economic Replacement Technique for Transformers”, IEEE, 2011, 978-1-4577-1002-5.

6. Sven C. Müller, Marc Osthues, ChristophRekowski, Ulf Häger, and Christian Rehtanz, “Techno-Economic Evaluation of Corrective Actions for Efficient Attainment of (N-1)-Security in Operation and Planning”, IEEE, 2013, 978-1-4799-1303-9.

7. T. Stetz, K. Diwold, M. Kraiczy, D. Geibel, S.

Schmidt, And M. Braun,” Techno-Economic Assessment Of Voltage Control Strategies In Low Voltage Grids”, Ieee Transactions On Smart Grid, Vol. 5, No. 4, 2014,

8. AntoniosMarinopoulos, PanagiotisBakas,

“Techno-economic evaluation of alternative configurations for very large scale PV power systems including energy storage” Ecological Vehicles and Renewable Energies (EVER), 2014,

9. G. Lambert-Torres, Member, F. Ely, P.K.

Biasoli, and C.H.V. de Moraes.

11. I. Chendong, "Monitoring paper insulation aging by measuring Furfural Contents in oil,"

in proc. 7Th Int. Symp. on High Volt. Eng.

1991.

(4)

4

12. A. M. Emsley and G. C. Stevens, "Review of chemical indicators of degradation of cellulosic electrical paper insulation in oil- filled transformers," IEE Proceedings Science, Measurement and Technology, vol. 141, pp.

324-334, 1994

13. K. T. Muthanna, A. Sarkar, K. Das and K.

Waldner, "Transformer insulation life assessment," IEEE Transactions on Power Delivery, vol. 21, pp. 150-156, 2006. IEEE Transactions On Power Delivery, Vol. 27, No.

4, October 2012

14. Miguel E. Rosillo, Carlos A. Herrera, and Guillermo Jaramillo ,”Advanced Thermal Modeling and Experimental Performance of Oil Distribution Transformers” IEEE Transactions On Power Delivery, Vol. 27, No.

4, October 2012

15. CsabaVörös High Voltage Laboratory

“Diagnostic evaluation of power transformers by an expert system”

16. Hui Ma, Tapan K. Sahaand Chandima Ekanayake “Statistical Learning Techniques and Their Applications for Condition Assessment of Power Transformer”

17. Z. Qian and Z. Yan “Fuzzy synthetic method for life assessment of power Transformer ”IEE Proc.-Sci. Meas. Technol., Vol. 151, No. 3, May 2004

18. A. E. B. Abu-Elanien and M. M. A. Salama,

"Asset management techniques for transformers," Electr. Power Syst. Res., vol.

80, pp. 456-464, 2010.

19. J. P. Van Bolhuis, E. Gulski and J. J. Smit,

"Monitoring and diagnostic of transformer solid insulation," IEEE Transactions on Power Delivery, vol. 17, pp. 528-536, 2002.

20. "IEEE guide for loading mineral-oil-immersed transformers," IEEE Std C57.91-1995, 1996.

21. L. Wenyuan, E. Vaahedi and P. Choudhury,

"Power system equipment aging," IEEE Power and Energy Magazine, vol. 4, pp. 52-58, 2006.

22. H. Herman, M. J. Shenton, G. C. Stevens and R. J. Heywood, "A new approach to condition assessment and lifetime prediction of paper and oil used as transformer insulation," in proc. the 2001 IEEE 7th International Conference on Solid Dielectrics, ICSD '01., 2001, pp. 473-476