Analysis of the Effect of Loading on the Transformers Usage Time

The reliability and stability of the system in the operation of the electric power system is very important, in order to provide comfort in service to consumers. The transformer is a very important component in the electric power system, because it is used as a voltage adjuster for the load being served. This study discusses the effect of loading and temperature on the life shrinkage of 36/60 MVA power transformers in block 3 and block 4 carried out at PT. PJB UBJ O&M PLTMG Arun Lhokseumawe, Aceh. From the calculation results after 4 years the transformer operates, if the transformer is given a 100% load, the transformer will experience an age difference of 2.52 p.u/day so that it has a remaining life for of 10 years. As for the transformer that is given a load of 90%, the transformer will experience an age difference of 1.44 p.u/day so that it has a remaining life to perform operations for another 18 years. Then for a transformer that is given a load of 80%, the transformer will experience an age difference of 0.67 p.u/day so that it will have a remaining life to carry out the operation again for another 38 years. From the above calculation, the origin of the temperature obtained for the ONAN type of cooler in block 3 is 0.71 p.u/day and in block 4 it is 0.70 p.u/day. While the ONAF type of cooler in block 3 is 0.004 p.u/day and in block 4 it is 0.005 p.u/day. This is in accordance with the regulation SPLN50/1982 regarding transformer life shrinkage.

Download Full-text

STUDI ANALISIS UFR (UNDER FREQUENCY RELAY) PADA GARDU INDUK PESANGGARAN

Jurnal SPEKTRUM ◽

10.24843/spektrum.2019.v06.i02.p07 ◽

2019 ◽

Vol 6 (2) ◽

pp. 45

Author(s):

Bhrama Sakti K.P. ◽

A.A. Gede Maharta Pemayun ◽

I Gede Dyana Arjana

Keyword(s):

Power Plant ◽

Power System ◽

Electric Power ◽

Recovery Time ◽

Electric Power System ◽

Calculation Results ◽

Working Principle ◽

Simulation Results ◽

System Frequency ◽

Frequency State

The disruption of the electric power system due to overcurrent causes a trip to the 3rd generator of pesanggaran power plant . This causes a decrease in frequency due to the system losing its supply. Frequency interference can be detected automatically with UFR (Under Frequency Relay). The working principle of UFR is to compare the value of the system frequency and the value of the frequency setting. The comparison will determine how much load is released to balance the generator supply. This study analyzes UFR performance at Pesanggaran Substation by simulating a case of the generator being released so as to produce a decreased system frequency state. The method used is by comparing the ETAP simulation results and calculation results. The results of the comparison obtained the system recovery time when the conditions (gen1 tripped), (gen1 and gen2 tripped), and (gen1, gen2, and gen3 tripped), each is 1.171s; 4,531s; and 4,514s.

Download Full-text

Dimensional standards for bushings applied to liquid filled power transformers and reactors why they are important to your electric power system

2008 IEEE/PES Transmission and Distribution Conference and Exposition: Latin America ◽

10.1109/tdc-la.2008.4641874 ◽

2008 ◽

Author(s):

K. Ellis

Keyword(s):

Power System ◽

Electric Power ◽

Electric Power System ◽

Power Transformers

Download Full-text

PENGARUH PENAMBAHAN PENDINGIN AIR PADA TRANSFORMATOR DAYA UNTUK PEMBEBANAN

Energi & Kelistrikan ◽

10.33322/energi.v9i1.55 ◽

2018 ◽

Vol 9 (1) ◽

pp. 8-15

Author(s):

Redaksi Tim Jurnal

Keyword(s):

Power System ◽

Electric Power ◽

Water Consumption ◽

Temperature Rise ◽

Electric Power System ◽

Power Transformers ◽

Water Cooling ◽

Ambient Temperatures ◽

Transmission And Distribution ◽

System Power

Power transformers are one of the important equipment in the electric power system. Power transformers are devices with the largest investment in a transmission and distribution substations. Currently, the use of power transformers at Marunda substations on average has reached 80% of rated load. Then require maximum of cooling transformers, to restrain the rate of the winding and oil temperature rise. Result of the research were obtained with the addition of water cooling at power transformers can be reduce the heat due to the high ambient temperatures. The results showed a decrease in temperature of 3°C, so can be used to add transformers loading of 2,51 MW. While of water consumption was 2,052 m3 per day.

Download Full-text

DETERMINATION OF “WEAK” BY POWER TRANSFORMERS RELIABILITY OF POWER SYSTEMS ACCORDING TO THE RESULTS OF FAILURE RISK ASSESSMENT UNDER EXTERNAL SHORT CIRCUITS

KPI Science News ◽

10.20535/kpisn.2021.2.236952 ◽

2021 ◽

Author(s):

Eugeniy I. Bardik ◽

Mykola P. Bolotniy ◽

Yaroslav S. Koval

Keyword(s):

Mathematical Model ◽

Risk Assessment ◽

Power System ◽

Electric Power ◽

Power Transformer ◽

Short Circuit ◽

Electric Power System ◽

Power Transformers ◽

Electrical Network ◽

Failure Risk

Background. The increase of technological violation intensity and its consequences severity is caused mainly by objectively existing aging and service life depletion of electrical equipment. The power industry liberalization exacerbates the reliable operation problem of the power system and requires identification of power system operation accompanied by the maximum emergency risk with possible cascade accidents development. Therefore, the model development task for assessment of the equipment failure risk based on the diagnostic results of technical condition in particular under short circuit in the external network is relevant today. Objective. The aim of the work is to develop a fuzzy mathematical model for probability assessment of power transformer failure in the presence of a windings defect, short circuit in external network and emergency risk assessment under power transformers out of service. Methods. The fuzzy set theory and fuzzy logic were used for developing a mathematical model of risk assessment of power trans- former failure. The problems of determining the “weak” in terms of power transformers reliability of power systems based on the results of failure risk assessment due to external short circuits were solved by methods of fuzzy logic and probabilistic-statistical simulation of electric power system modes. Results. The necessity of complex simulation of electric power system modes is substantiated for probability assessment of power transformer failure under electrical network disturbances. The simulation of technical condition of power transformer windings was carried out. The short circuit influence on operability level of power transformers of electric power system was investigated. The quantitative indicators of operational risk of electric power system were determined under power transformers out of service. Conclusions. The linguistic mathematical model for estimating the failure probability of power transformer windings in the presence of defect and short circuit in electrical network has been developed to determine the quantitative indicators of emergency risk in power system.

Download Full-text