22-12-2014, 06:12 PM
surge current limiting using superconductors
|
surge current limiting using superconductors wiki
|
surge current limiting using superconductors
15-04-2017, 02:25 PM
Systems designed to use superconductors to limit fault currents in electrical networks are being tested. The authors describe superconducting fault current limiter (SCFCL) that can be classified into resistive or shielded core types. The characteristics and operation of each type of device are described. Both the shielded type and the resistive types of SCFCL use the same amount of superconducting material to achieve a given limiting behavior. This is because the nominal power per conductor volume is determined by the product of the field induced by failure and the critical current, which is the same for both devices, assuming that the same type of superconducting material is used. The shielded core limiter operates only with alternating current and is much larger and heavier than the resistive SCFCL. While there is only one large program in the type of low-temperature SCFCL, more than 10 major projects are underway worldwide in the type of high-temperature device. The main reason is the lower cost of HTS cooling.
The increase in the power generation capacity of the electric power systems has led to an increase in the level of fault current that can exceed the maximum designed short circuit ratings of the switching apparatuses. Many conventional protective devices installed to protect the excessive fault current in electrical power systems, especially in power plants, are the circuit breakers triggered by an overcurrent protection relay. They have the response time delay that allows the initial two or three cycles of fault current to pass before being triggered. The Superconductor Fault Current Limiter (SFCL) is an innovative electrical equipment that has the ability to reduce the level of fault current within the first fault current cycle. Applying the fault current limiter (FCL) would not only reduce stress on network devices, but could also provide a connection to improve reliability of the power system. There are several types of FCL, which are made of different superconducting materials and have different designs. They are classified into three broad types: the resistive type, the inductive type and the bridge type SFCL. The operational characteristics of SFCL introduced in a simplified power transmission model system were discussed. Finally it was revealed that SFCL could satisfy the fault current suppression functions and improve the stability of the power system.
The increase in the power generation capacity of the electric power systems has led to an increase in the level of fault current that can exceed the maximum designed short circuit ratings of the switching apparatuses. Many conventional protective devices installed to protect the excessive fault current in electrical power systems, especially in power plants, are the circuit breakers triggered by an overcurrent protection relay. They have the response time delay that allows the initial two or three cycles of fault current to pass before being triggered. The Superconductor Fault Current Limiter (SFCL) is an innovative electrical equipment that has the ability to reduce the level of fault current within the first fault current cycle. Applying the fault current limiter (FCL) would not only reduce stress on network devices, but could also provide a connection to improve reliability of the power system. There are several types of FCL, which are made of different superconducting materials and have different designs. They are classified into three broad types: the resistive type, the inductive type and the bridge type SFCL. The operational characteristics of SFCL introduced in a simplified power transmission model system were discussed. Finally it was revealed that SFCL could satisfy the fault current suppression functions and improve the stability of the power system.
|
« Next Oldest | Next Newest »
|
