25-05-2012, 05:26 PM
FAULT CURRENT LIMITERS: AN OVERVIEW
FAULT CURRENT LIMITERS.pdf (Size: 250.14 KB / Downloads: 60)
WHAT IS A FCL?
A fault current limiter is a device that uses superconductors to instantaneously limit or reduce unanticipated electrical surges that may occur on utility distribution and transmission networks.
WHY DO WE NEED THE FCL?
When an unplanned event, such as lightning or downed power lines, occurs, a large surge of power can be sent through the grid resulting in a fault. A fault is any abnormal situation in an electrical system in which the electrical current may or may not flow through the intended part/s at an abnormal level and can result in a partial or total local failure in the functioning of an electric system. Serious faults can generate surge currents more than one hundred times the normal operating currents. These faults can result in damage to expensive grid-connected equipment.
The development of new generating facilities and network upgrades can greatly increase the potential fault current on a network. The FCL eliminates or limits the fault current increases resulting when new generation and network upgrades occur. This potential for increased fault current makes it imperative that utilities invest in protective measures such as: new substations, splitting existing substation busses, or using multiple circuit breaker upgrades. These protective measures are extremely expensive to install and maintain. FCL's eliminate or greatly reduce the
financial burden on the utilities by reducing the wear on circuit breakers and protecting other expensive equipment.
WHAT ARE FCL BENEFITS?
According to the DOE, utilities pay hundreds of millions of dollars each year to maintain and add new circuit breakers to their transmission systems to protect the grid. The DOE then explains that investing in “smart technologies” such as FCL can save billions of dollars on transmission and delivery (T&D) equipment and power plants. Utility benefits from FCL include increased safety, reliability, and power quality. Utilities can reduce or eliminate the cost of circuit breakers and fuses by installing FCL. At the same time, these allow utilities to avoid or delay upgrading existing circuit breakers and electrical substations to handle ever higher electrical surges. Fault currents in transformers, for instance, can run 10-20 times the steady state design current. FCL can reduce these fault currents to levels not exceeding 3-5 times the steady state current, protecting and extending the life of transformers and associated utility equipment.
OTHER FCL BENEFITS:
• Reduce or eliminate wide-area blackouts, far fewer localized disruptions, and faster recovery when disruptions do occur
• Provide protection to T&D equipment, eliminate or reduce replacement of T&D equipment (i.e. circuit breakers)
• Avoid split buses, opening bus-tie breakers
• Higher system reliability
• Reduce voltage dips
• Enhance grid stability. Enables the creation of a safer, more reliable, more efficient, and affordable power delivery system
SuperPower, Inc.
SuperPower's High Temperature Superconducting (HTS) Fault Current Limiter (SFCL) offers a device designed for transmission voltages, with the initial target for operation at 138kV. Operational feasibility is expected to be made possible by SuperPower's second-generation (2G) HTS material, which has very rapid response and recovery times compared to alternative materials.
Distinguishing features of SuperPower’s FCL Program:
• Transmission-level device (138 kV) – highest voltage FCL to address utilities’ most significant needs
FAULT CURRENT LIMITERS.pdf (Size: 250.14 KB / Downloads: 60)
WHAT IS A FCL?
A fault current limiter is a device that uses superconductors to instantaneously limit or reduce unanticipated electrical surges that may occur on utility distribution and transmission networks.
WHY DO WE NEED THE FCL?
When an unplanned event, such as lightning or downed power lines, occurs, a large surge of power can be sent through the grid resulting in a fault. A fault is any abnormal situation in an electrical system in which the electrical current may or may not flow through the intended part/s at an abnormal level and can result in a partial or total local failure in the functioning of an electric system. Serious faults can generate surge currents more than one hundred times the normal operating currents. These faults can result in damage to expensive grid-connected equipment.
The development of new generating facilities and network upgrades can greatly increase the potential fault current on a network. The FCL eliminates or limits the fault current increases resulting when new generation and network upgrades occur. This potential for increased fault current makes it imperative that utilities invest in protective measures such as: new substations, splitting existing substation busses, or using multiple circuit breaker upgrades. These protective measures are extremely expensive to install and maintain. FCL's eliminate or greatly reduce the
financial burden on the utilities by reducing the wear on circuit breakers and protecting other expensive equipment.
WHAT ARE FCL BENEFITS?
According to the DOE, utilities pay hundreds of millions of dollars each year to maintain and add new circuit breakers to their transmission systems to protect the grid. The DOE then explains that investing in “smart technologies” such as FCL can save billions of dollars on transmission and delivery (T&D) equipment and power plants. Utility benefits from FCL include increased safety, reliability, and power quality. Utilities can reduce or eliminate the cost of circuit breakers and fuses by installing FCL. At the same time, these allow utilities to avoid or delay upgrading existing circuit breakers and electrical substations to handle ever higher electrical surges. Fault currents in transformers, for instance, can run 10-20 times the steady state design current. FCL can reduce these fault currents to levels not exceeding 3-5 times the steady state current, protecting and extending the life of transformers and associated utility equipment.
OTHER FCL BENEFITS:
• Reduce or eliminate wide-area blackouts, far fewer localized disruptions, and faster recovery when disruptions do occur
• Provide protection to T&D equipment, eliminate or reduce replacement of T&D equipment (i.e. circuit breakers)
• Avoid split buses, opening bus-tie breakers
• Higher system reliability
• Reduce voltage dips
• Enhance grid stability. Enables the creation of a safer, more reliable, more efficient, and affordable power delivery system
SuperPower, Inc.
SuperPower's High Temperature Superconducting (HTS) Fault Current Limiter (SFCL) offers a device designed for transmission voltages, with the initial target for operation at 138kV. Operational feasibility is expected to be made possible by SuperPower's second-generation (2G) HTS material, which has very rapid response and recovery times compared to alternative materials.
Distinguishing features of SuperPower’s FCL Program:
• Transmission-level device (138 kV) – highest voltage FCL to address utilities’ most significant needs