Título do trabalho. Experience in UHV test of insulator set and fittings for a 800 kv DC transmission line. Presenter: José Antonio CARDOSO

Transcription

1 Centro de Pesquisas de Energia Elétrica - CEPEL CEPEL Experience in UHV test of insulator set and fittings for a 800 kv DC transmission line José Antonio CARDOSO 1, Alexandre NEVES 1 and Orsino OLIVEIRA Filho Título do trabalho 1 Electrical Energy Research Center Cepel, 2 Consultant Brazil PAPER 051 CIGRE-IEC 2016 Colloquium Hotel Bonaventure Montréal, Québec Canada May 9-11, nd International Colloquium on EHV and UHV (AC & DC) Autor/apresentador Presenter: José Antonio CARDOSO Área

2 OUTLINE INTRODUCTION FEASIBILITY ANALYSIS OF THE REQUESTED TESTS Voltage source Clearances Mounting and mechanical analysis Corona check TEST PROCEDURE: RIV AND CORONA Remarks about the test procedure RESULTS RIV and corona test results: RIV test results CONCLUSION

3 INTRODUCTION Long Distance Generation to Load Center Transmission Lines UHVDC 800 kv New Challenges and requirements on ordinary and R&D tests Cepel is planning the construction of a new UHV laboratory. Currently, some UHV test performed in the existent indoor HV lab Experience with some tests on insulator strings and fittings as well as on the overhead line conductor designed to a HVDC

4 FEASIBILITY ANALYSIS OF THE REQUESTED TESTS UHV test in a standard HV Lab Constraints Test voltage source (rated 1000 kv, test voltage 1.1 x 800 kv) Dimensions: (44 x 30 x 24 m) clearances test arrangements x useful area of the HV lab UHV DUT greater and heavier: mechanical and technical requirements for the crane system (photos)

5 TEST ARRANGEMENT

6 TEST PROCEDURE: RIV AND CORONA Same test arrangement RIV (Adapted from AC test procedure): Steps of one-minute, avoiding the occurrence of ionization process around the object. The maximum value from all pulses was considered as the valid result. Calibration: the injection point was kept close to the coupling capacitor, instead of close to the test object, for all arrangements. All generated pulses are registered along the test arrangement. The UV camera was used as a complementary tool to find discharge points. Corona Test: UV camera: Inception and Extinction Voltage The inception voltage is identify through the UV image by the discharge shape.

7 RESULTS RIV under DC voltages: o Poor repetitivity, expurious and low number of events o Reason: Charge accumulation from ionization process o Consequence: unexpected results Three sets of results for RIV test RIV and corona test results: The results of RIV and Corona tests were very well correlated.

8 CONCLUSIONS Tests on 800 kv DC equipment were successfully performed in a standard HV laboratory. For the RIV and Corona tests, a more compact test set up is better to avoid the disturbances and calibration problems. The ambient conditions, particles and insects in the air also play an important role during the tests under HVDC voltages. The test procedures for DC should be specific for this type of voltage, as it is not always standardized. So, as an suggestion, the procedure must be informed prior the test. The UV camera showed to be a very useful tool to detect and register images related to the corona effect, independent of the luminosity and type of the system voltage (AC or DC). The UV camera was also a valuable tool in the RIV test procedure, allowing expurious discharge to be detected during the test.

9 THANK YOU José Antonio CARDOSO Electrical Energy Research Center Cepel, Brazil Centro de Pesquisas de Energia Elétrica - CEPEL