Analysis of the venezuelan power system loss variation with the series compensation at s/s tablazo out of service

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Analysis of the Venezuelan power system loss variation with the series compensation at S/S Tablazo out of service
F. Garayar, and M. Riccuci

Abstract-- This paper shows the loss variation for the Venezuelan Interconnected Power System as a whole and for the transmission link from Substation Yaracuy to the tern regions,when the series capacitors installed at Substation Tablazo on the 400kV lines N° 1 and N° 2 to Substation Yaracuy are out of service. The results confirm that the total losses in the interconnected power system are indeed higher than the ones on normal conditions, an that the loss increase is bigger on the Interconnected Power System than on the Yaracuy transmission link to the western area, pointing out that the redistribution of the power flow when the seriescapacitors are out of service results in a reduction of transportation costs for ENELVEN ( utility depending on exports from Yaracuy), but at the same time increases such cost for all other utilities of the Venezuelan System. Index Terms--Load flow analysis, Losses.

order to minimize the flow through the lines that have wheeling charges, ENELVEN solicited put out of service the series capacitorsinstalled on the Yaracuy - Tablazo 400 kV lines N° 1 and 2 while the SIN operation conditions allows it, with the purpose of maximizing the power flow through the line N° 3. Considering the disconnection of the series capacitors, increases the connection impedance between S/S Yaracuy and S/S Tablazo, a preliminary study took place to analyze the incidence of this modality of operation on the SINlosses III. METHODOLOGY For three different SIN load scenarios: Peak, Medium and Low, the SIN and Yaracuy Outflow losses were determined, when operating with all the series capacitors of the Yaracuy Tablazo 400 kV lines in service or only the series capacitor line N° 3 in service. IV. ANALYZED CASES Three SIN load scenarios were analyzed: • Peak : • Medium: • Low: at 20:00 hours at 10:30 hours at04:00 hours

I. NOMENCLATURE S/S - Substation SC - Series Capacitors SIN - National Interconnected System

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II. INTRODUCTION

he Yaracuy - Export is defined by the power flow transmitted from the substation Yaracuy to ENELVEN, ENELCO and CADAFE WEST companies, through the Yaracuy-Tablazo 400 kV lines, Yaracuy-Morochas 230 kV lines and Yaracuy-Acarigua 230 kV lines. The equipment used forthe energy exchanges are assets of the different companies and they benefit from these connections with the SIN and consequently agreements of payment by the use of these equipment exist, as well as the distribution of the costs associated to the energy losses of this interchange. Among the commercial agreements that prevails on the Yaracuy - Tablazo 400 kV lines stands out that the energytransmitted through the Yaracuy - Tablazo 400 kV line N° 3 (EDELCA property) does not pay wheeling. In that sense, in

For the three scenarios the operation with all series capacitors of the Yaracuy - Tablazo 400 kV lines in service or only the series capacitor of the line N° 3 in service was analyzed, obtaining as a result, six (6) cases: Case 1: Case 2: Case 3: Case 4: Case 5: Case 6: Peak load, allthe SC in service peak load, only line N° 3 SC in service Medium Load, all the SC in service Medium load, only line N° 3 SC in service Low load, all the SC in service Low load, only line N° 3 SC in service.

F. Garayar is with EDELCA, OPSIS, Caracas, VENEZUELA (e-mail: fgarayar@edelca.com.ve). M. Riccuci is with EDELCA, OPSIS, Caracas, VENEZUELA (e-mail: mriccuci@edelca.com.ve).

It isimportant to indicate that due the characteristics of the load curve of the western region, the SIN medium load case corresponds to the low load Yaracuy Outflow. (see results tables) and the SIN low load case to the medium Yaracuy

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outflow case. V. ANALYSIS OF THE RESULTS The following tables shows the results of the analyzed cases. Table I shows the magnitude of the Yaracuy Outflow and the sum...