Considering the characteristics of the UHVAC Pilot Project in China,the importance of study on electromagnetic transient overvoltage in UHVAC projects is demonstrated in this paper.Through analysis and comparison on t...Considering the characteristics of the UHVAC Pilot Project in China,the importance of study on electromagnetic transient overvoltage in UHVAC projects is demonstrated in this paper.Through analysis and comparison on the simulation programs for electromagnetic transient overvoltages,EMTP is then recommended for the UHVAC Pilot Project in China.The element models in EMTP used in simulating power frequency overvoltage and power resonance of non-entire phase operation,etc.,are introduced.The paper also points out that extra attention will be needed when simulating power frequency sequence parameters and line corona.The research outcome provides valuable references for both oversea and domestic UHVAC projects.展开更多
The construction of the UHVAC test base of SGCC is an important component of the pilot project on UHVAC power transmission and transformation in China. This paper introduces the layout, technical requirements and main...The construction of the UHVAC test base of SGCC is an important component of the pilot project on UHVAC power transmission and transformation in China. This paper introduces the layout, technical requirements and main test functions of the UHVAC test base as well as difficulties during construction. It lays stress on the characterization of a 1 000-kV single-circuit test line, a 1 000-kV one-tower double-circuit test line, a full voltage test site for UHV equipment, a climate laboratory, a corona cage and a long-wave-front impulse voltage generator.展开更多
UHV transmission technology is characterized with long transmission distance, large transmission capacity, low line loss and less land use. In China, SGCC had completed its 1 000 kV UHVAC pilot project by the end of 2...UHV transmission technology is characterized with long transmission distance, large transmission capacity, low line loss and less land use. In China, SGCC had completed its 1 000 kV UHVAC pilot project by the end of 2008. This paper reviews the construction of the project from the aspects of technology research and development, engineering design, equipment development, transportation and on-site construction, commissioning and operation. Since put into operation, the project has shown excellent performance till now.展开更多
Strong DC coupling with weak AC and large-scale renewable energy integration are the two significant characteristics of ultra-high-voltage AC/DC(UHVAC/DC)hybrid power grids in China.Strong coupling between AC and DC g...Strong DC coupling with weak AC and large-scale renewable energy integration are the two significant characteristics of ultra-high-voltage AC/DC(UHVAC/DC)hybrid power grids in China.Strong coupling between AC and DC grids and the different integration performance of renewable energy sources have profoundly changed the stability characteristics of the power system.The traditional stability control system is inadequate for the stability control of UHVAC/DC power grids.This paper analyzes the requirements for constructing an integrated defense system in a UHVAC/DC hybrid power grid(i.e.power system protection).The definition,connotation,and designing principles of power system protection are put forward.The relationship between the power system protection and the traditional three-defense lines is investigated.The design principles,general hardware structure and main functions of a power system protection are presented.Key problems and technologies are specified in the construction of the power system protection.展开更多
The studied sending-terminal’s UHVDC converter transformer with the UHVAC grid is currently one of the largest-capacity converter transformers,which is characterized by strong support for the large-scale grid power d...The studied sending-terminal’s UHVDC converter transformer with the UHVAC grid is currently one of the largest-capacity converter transformers,which is characterized by strong support for the large-scale grid power delivering out,strengthening grid’s fault tolerance and backup capability,improving grid operation’s flexibility and security,lowering the short-circuit currents.The proposed single-active-part converter transformer structure is well-designed,including the single-phase five-leg iron core,the special winding arrangement,the special structure of the spacers and angle rings,and so on,which is a smaller footprint,easier to install and test on site,but is more challenging in the structural design due to the critical railway transportation limitations on aspects of both size and weight.The feasibility of the proposed structure schema is verified by a series of tests,concerning the wave process,the short circuit force,the temperature field,the main insulation,and so on.Among them,the main insulation’s electric fields at the import positions are verified to be reasonable,including the AC impressed voltage test,the DC impressed voltage test,and the polarity reversal test.It shows that the proposed single-active-part design scheme is practicable and conductive to manufacture and application for the UHV large-capacity converter transformers.展开更多
文摘Considering the characteristics of the UHVAC Pilot Project in China,the importance of study on electromagnetic transient overvoltage in UHVAC projects is demonstrated in this paper.Through analysis and comparison on the simulation programs for electromagnetic transient overvoltages,EMTP is then recommended for the UHVAC Pilot Project in China.The element models in EMTP used in simulating power frequency overvoltage and power resonance of non-entire phase operation,etc.,are introduced.The paper also points out that extra attention will be needed when simulating power frequency sequence parameters and line corona.The research outcome provides valuable references for both oversea and domestic UHVAC projects.
文摘The construction of the UHVAC test base of SGCC is an important component of the pilot project on UHVAC power transmission and transformation in China. This paper introduces the layout, technical requirements and main test functions of the UHVAC test base as well as difficulties during construction. It lays stress on the characterization of a 1 000-kV single-circuit test line, a 1 000-kV one-tower double-circuit test line, a full voltage test site for UHV equipment, a climate laboratory, a corona cage and a long-wave-front impulse voltage generator.
文摘UHV transmission technology is characterized with long transmission distance, large transmission capacity, low line loss and less land use. In China, SGCC had completed its 1 000 kV UHVAC pilot project by the end of 2008. This paper reviews the construction of the project from the aspects of technology research and development, engineering design, equipment development, transportation and on-site construction, commissioning and operation. Since put into operation, the project has shown excellent performance till now.
文摘Strong DC coupling with weak AC and large-scale renewable energy integration are the two significant characteristics of ultra-high-voltage AC/DC(UHVAC/DC)hybrid power grids in China.Strong coupling between AC and DC grids and the different integration performance of renewable energy sources have profoundly changed the stability characteristics of the power system.The traditional stability control system is inadequate for the stability control of UHVAC/DC power grids.This paper analyzes the requirements for constructing an integrated defense system in a UHVAC/DC hybrid power grid(i.e.power system protection).The definition,connotation,and designing principles of power system protection are put forward.The relationship between the power system protection and the traditional three-defense lines is investigated.The design principles,general hardware structure and main functions of a power system protection are presented.Key problems and technologies are specified in the construction of the power system protection.
文摘The studied sending-terminal’s UHVDC converter transformer with the UHVAC grid is currently one of the largest-capacity converter transformers,which is characterized by strong support for the large-scale grid power delivering out,strengthening grid’s fault tolerance and backup capability,improving grid operation’s flexibility and security,lowering the short-circuit currents.The proposed single-active-part converter transformer structure is well-designed,including the single-phase five-leg iron core,the special winding arrangement,the special structure of the spacers and angle rings,and so on,which is a smaller footprint,easier to install and test on site,but is more challenging in the structural design due to the critical railway transportation limitations on aspects of both size and weight.The feasibility of the proposed structure schema is verified by a series of tests,concerning the wave process,the short circuit force,the temperature field,the main insulation,and so on.Among them,the main insulation’s electric fields at the import positions are verified to be reasonable,including the AC impressed voltage test,the DC impressed voltage test,and the polarity reversal test.It shows that the proposed single-active-part design scheme is practicable and conductive to manufacture and application for the UHV large-capacity converter transformers.
