Zhiyuan Gao

Fabrication and Tests of a 1 MJ HTS Magnet for SMES

In this paper, the design, fabrication and tests of a I MJ HTS magnet for SMES was presented. The magnet was fabricated by BSSCO tapes, it consisted of 44 pancakes, the inner diameter of the winding is 400 mm, the outer diameter is 568 mm and the height is 648 mm, the inductance is 6.38 H and the rated operation current is 560 A at 4.2 K. The tests show the magnet could be operated at the design parameters. The magnet will be used for the 1 MJ/500 kVA SMES unit which will be demonstrated at a 10 kV substation in Beijing.

Design of a 380 m DC HTS Power Cable

High temperature superconducting (HTS) power cable is an effective power transmission utility with large capacity, high efficiency, and low loss, especially in DC power transmission. This paper describes the design of a 380 m HTS power cable with rated current of 10 kA for an aluminum electrolysis enterprise. The power cable connects the rectifier at a substation at one end with the bus bar of an aluminum electrolysis plant at the other end at Henan Zhongfu Industrial Co. LTD. The power cable will be energized in late of 2010. The design of the cable conductor, cryogenic envelope, termination, refrigeration, and online monitoring system of the 380 m HTS power cable are discussed in this paper.

Development of the World's First HTS Power Substation

With the increasing depletion of fossil fuels and growing environmental pressure, the mankind has got known the need to vigorously develop the renewable energy and the energy-saving technology. The high Tc superconducting (HTS) power technology will be very helpful to enhance the stability, reliability, and efficiency and transmission capacity of the power grid which would be dominated by the renewable energy. In this paper, we will report the installation and operation of a 10 kV HTS power substation which includes a 75 m/1.5 kA HTS power cable, a 10 kV/1.5 kA HTS fault current limiter, a 1 MJ/0.5 MVA high Tc SMES and a 630 kVA/10 kV/0.4 kV HTS power transformer.

Development of a 10 kA HTS DC Power Cable

The new energy revolution which will be dominated by renewable energy will need to develop a corresponding new power grid. Based on the characteristics of renewable energy resources, and the stability problem of AC network, it was proposed that the DC-based transmission grid should be developed in the future. The high Tc Superconducting (HTS) power cable will be a competitive candidate for large-capacity power transmission of renewable energy. In this paper, the progress of the development of a 360 m/10 kA HTS DC power cable is presented, and the prospects of HTS cable is discussed.

Development of HTS transmission power cable

A 1500 A/6 m HTS DC transmission power cable has been developed and tested at the Institute of Electrical Engineering, Chinese Academy of Sciences. The conductor of the HTS cable consists of 4 layers of Bi-2223/Ag tapes helically wound on a flexible stainless steel former. The Bi-2223/Ag tapes have been developed by the Northwest Institute for Nonferrous Metal Research and the Beijing General Research Institute for Nonferrous Metals. The cable core has a 45.3 mm outer diameter and 6 m length and is housed in a cryogenic envelope. The E-I characteristic and the total joint resistance of the cable have been measured at 77 K. The critical current of the cable is 1473 A and the total joint resistance is 0.1 /spl mu//spl Omega/ at 77 K. The main properties of the Bi-2223/Ag tape and the development and test results of the HTS cable are presented in this paper.

Design, Fabrication, and Tests of Three HTS Coils for a Model Fault Current Limiter

The design, fabrication and tests of three high temperature superconductor (HTS) coils for a rectifier-type model fault current limiter (FCL) were presented. The field distributions in the coil were numerically analysed by FEM. Based on the field distributions and the strong anisotropic characteristics of Bi2223/Ag tape, the HTS coils were designed and fabricated. The inner diameter and the height of the coils were 80 mm and 94 mm, respectively. Each of the coils consisted of 8 double pancakes. Every double pancake consisted of 103 turns with 35 meters of Bi-2223/Ag tape. After the characteristics of the coils were tested in liquid nitrogen, three of the coils were assembled in their nonmetallic-material cryostats and works with the model FCL.

Testing and Demonstration of a 10-kA HTS DC Power Cable

A 10-kA/360-m high-temperature superconducting (HTS) dc power cable has been developed and installed in 2012 in central China. The cable is connecting a rectifier at a substation to a bus bar of an aluminum electrolysis plant. Before operating in the power grid, a series of testing on the performance of the cable was conducted. The testing results show that the performance meets the operational requirements and that the critical current of the cable exceeds 12.5 kA. The 10-kA HTS cable was successfully energized at the Henan Zhongfu Industrial Company Ltd., Gongyi, China, on September 26, 2012. Since then, the cable has been stably and reliably supplying power for the companys aluminum electrolyzing plant.

Development and Demonstration of a 1 MJ High-Tc SMES

A superconducting magnetic energy storage system (SMES), with stored energy of 1 MJ and compensation power of 0.5 MVA, has been developed successfully, and now is operating at the worlds first superconducting power substation at Baiyin National High-Tech Industrial Development Zone, Gansu Province, China. The SMES employs a high Tc superconducting magnet, which consists of 44 pancakes, operates at 4.2 K in liquid helium, and is cooled down by 4 G-M cryo-coolers. The SMES connects to a 10.5 kV power grid by the use of a power conversion system. Since 16 February, 2011, the SMES has been operating reliably, and providing good-quality power for three companies.

Design of a 1 MJ/0.5 MVA HTS Magnet for SMES

SMES is a potential solution for power quality issues. The development of a 1 MJ/0.5 MVA SMES is now at its final stage and the device will be put into operation in a live power grid of 10 kV in late of 2006 at a substation in the suburb of Beijing, China. The design and analysis of the SMES coil has been completed and magnetic flux density distribution of and electromagnetic force on the coil has been analysed by means of FEM. The cryogenic system adopts bath cooling method and employs four cryo-coolers to re-liquefy the evaporated helium. And HTS current leads are utilized to reduce heat loss.

Development of HTS AC Power Transmission Cables

Along with the rapid growth of the national economy in China, the electric utility is faced with an ever rising demand for electricity and the problem to solve large capacity power transmission. Under the support of the High Technology Research & Development Program of China, a 1.5 kA/10.5 kV 10-m long 3-phases HTS transmission power cable and a 75-m long, 3-phase, 10.5 kV/1.5 kA HTS power cable have been developed successfully by the Institute of Electrical Engineering, Chinese Academy of Sciences. The 75-m long HTS power cable operates now at a local live distribution grid of 6.6 kV to supply electric power for Changtongs factory in Baiyin, Gansu Province. The cable operates stably and reliably over 7000 hours since December 2004.