Superconducting DC Cable for Railway applications

SUBMITTED BY:KASHISH SRIVASTAVA

ELECTRICAL ENGINEERING(3rd year)

Contents

Introduction Semiconductor and its Properties Cross-sectional view of htsc Htsc cables and transformers Applications Power transmission cables Advantages and disadvantages Conclusion

Introduction Superconductors(SC) are materials which exhibit zero

resistivity below a certain temperature.

The phenomenon of superconductivity was first observed in mercury by the Dutch physicist Heike Kamerlingh Onnes in 1911 .

Discovery of High Temperature superconductors in 1986 reignited interest in superconducting Power application because of lower cooling costs.

What is Superconductivity?

Superconductivity is a phenomenon observed in several metals and ceramic materials cooled to temp. ranging from near abs. zero (0 K, -2730 C) to liquid nitrogen temp. ( 77 K, -1960 C), their electrical resistance drops with a jump down to zero.

The temperature at which electrical resistance is zero is called the critical temperature (Tc).

MERCURY

The First Superconductor Material Discovered in 1911Critical Temp = 4.2 K (-269 C)

HTS Cables..

Superconducting property about temp 70[K] .Cooled by liquid Nitrogen [Liquid N2].

  Properties of Superconductors:-

Zero resistivity. Critical temperature (Tc). Critical magnetic field (Bc). Critical current (Jc).

Applications of HTSC

Superconducting transmission line cables Superconductor magnetic energy storage (SMES) Superconducting generator Magnetic separators Magnetic Levitation Superconducting magnets in generators Particle accelerators Rotating machinery

Development of High-Temperature Superconducting Transformers

WHAT IS THE TRANSFORMER ?Transformer is a static device which transfer electrical energy from one circuit to another circuit without changing its frequency. Transformer is an heart of substation.

Cross-sectional view of HTS cable

A dc feeding system with an overhead contact line, in which a single core HTS dc cable bypasses a normal cable.

A dc feeding system with an overhead contact line in which HTS dc cables of double core type or two-in-one type bypass the normal feeder cable.

Schematic distribution of a conventional feeding network

The radiation heat load,

Power Transmission Cables

Since 10% to 15% of generated electricity is dissipated in resistive losses in transmission lines, the prospect of zero loss superconducting transmission lines is appealing

In prototype superconducting transmission lines at Brookhaven National Laboratory, 1000 MW of power can be transported within an enclosure of diameter 40 cm.

Advantages of superconducting cable over underground cable:- Zero resistance Small physical size Reduced clearance for terminal facilities Higher reliability Overload capability

Disadvantages

High cost. Difficult for maintaining cryoogenic temp.

required for cooling. Generator fails to work ,if the SC leave their

superconductivity state.

Conclusion

Further R&D is in progress to synthesize new materials which might attain superconductivity at even room temperatures

Such an invention can truly revolutionize the modern world of electronics, power & transportation

They help by ensuring good quality power and system-stability.

References

http://en.wikipedia.org/wiki/Superconducting_magnetic_energy_storage

http://www.ornl.gov/ http://www.superconductorweek.com/ http://www.ieeexplore.org/

Thank You