Energy Savings with Amorphous Metal Core Distribution Transformers
“POWER FOR ALL” mission requires generation capacity to be at least 2,00,000 MW at least by 2012 from existing level of 1,14,000 MW. This would approximately mean an investment of INR 3,50,000 crores roughly to transmit this power to be used.
India currently has Transmission and Distribution Losses of 29% which results in a loss of revenue of INR 76000 crores. We aim to reduce the losses to 15 % by 2012 which can be greatly possible by implementing energy efficient equipments.
Load Losses Or Coil Losses: the loss is proportional to the square of load drawn.
No Load Losses Or Core Losses: the loss is continuous, independent of load.
Minimizing No Load Loss Represents High Savings Potential Using Amorphous Metal Transformers Capitalizes On This Opportunity
Why Amorphous Metal for Transformers?
No Load Losses
► Hysteresis Loss
Random molecular structure of amorphous metal causes less friction than SiFe when a magnetic field is applied. This unique property which allows ease of magnetization & demagnetization significantly lowers hysteresis losses in amorphous metals.
► Eddy Current Loss
Amorphous metals have very thin laminations. Thin laminations result in lower eddy current losses as compared to SiFe.
Amorphous Metal Casting Process
► Molten metal feed through small nozzle slot onto rapidly moving, water cooled substrate.
► Rapid solidification - 106 oC per second.
► ~100 kilometer per hour line speed.
► Continuous operation with multi-hub, indexing winder.
► Careful raw materials and melt chemistry control.
► Extremely tight position and speed control.
► In line sensing and control.
Amorphous Metals are Easy To Magnetize & Demagnetize
► Regular and Periodic Arrangement.
► Defects in structure hinder magnetic domain movement.
► Crystalline structures have easy and hard directions for magnetization.
► Requires thermo-mechanical grain orientation processing for best properties.
► Random Arrangement of atoms.
► No structural defects to hinder domain movement.
► Magnetic field annealing for optimized directional properties.
Amorphous Metal Transformer Benefits
No load losses are 20% to 30% of conventional transformers.
► Show a payback in ~3 years, after which the benefits continue for the life of the product irrespective of loading.
► Payback period further reduces if effect of system harmonics is considered.
Savings In Transformer Repair Cost
► Fast & easy repair due to modular construction
Savings Due To Long Service Life
► High reliability
Reliability & Quality
Excellent Short Circuit Capability:
► Robust single coil construction addresses axial component of short circuit forces.
► Interlayer bonding using epoxy dotted paper addresses radial component of short circuit forces.
Better Overloading Capacity:
► Lesser heat generation due to lower losses.
► Lesser impact on aging of insulation.
Assured Product Quality:
► Use of single quality (grade) core material.
► Highly mechanized & standardized process to achieve consistency in quality.
Ease Of Manufacture & Repair:
► Easy lacing & unlacing of core for coil installation.
Uniform Transformer Designs:
► Transformer designs through software to achieve optimum performance parameters.
More On Total Owning Cost Loss Evaluation Factors
► TOC loss evaluation factors (A&B) impact future electrical energy usage.
► Buying decisions affect usage today and 30 years into the future.
► Current TOC methods do not incorporate several key factors.
E-Factor: Societal & economic costs of generation related CO2, SO2 and NOX emissions.
H-Factor: Increased transformer losses due to power quality (harmonics) issues.
“E” Factor: Capturing The Environmental Cost
► Increasing awareness of efficient transformers impact on greenhouse gas emission reduction.
► Standard method to capture effects in TOC not yet accepted.
► Environmental cost can logically be added to “A” and “B” factors.
► Cost per ton of pollutant times tons per kWh.
“H” Factor: Dealing With Real World Power Quality
► Growing concern over power quality and impact on T&D systems
► Harmonics - high frequency components added to current and voltage wave forms.
► Computer power supplies, motor drives, fluorescent lighting, etc.
► Effects on transformer operating costs not fully appreciated.
► Focus on transformer overheating and life (winding and stray losses) - not operating costs.
► Core loss and total effects not yet recognized.
► Transformer losses not generally monitored in-situ.
► Growing evidence that harmonics have significant impact on transformer losses and operating costs.
► Impact much less for Amorphous Metal Transformers.
► AM low eddy current losses, AM’s advantage increases with increasing frequency.
► Reports from industrial users in Japan - AMT savings larger than expected.
► ERDA (India) - controlled field studies.
► Harmonics are prevalent.
► Coil and core losses increase.
► Increase is less for AM cores.
► TOC load loss and no load loss concepts are not adequate.
► Core loss no load loss.
► Depends on harmonics and load.
► Research continues.
Amorphous Metal Core Manufacturing
► Flexible processes and simple tooling for multiple core sizes.
► Precise dimensional control for consistent properties and ease of core/coil assembly.
► Bonded edges for core integrity and transformer reliability.
► Magnetic field annealing for stress relief and magnetic property optimization.
► Core properties tested 100% for consistent transformer loss performance.
Amorphous Metal Coil Manufacturing
► Coil technology is key factor for cost effective AMT’s.
► One piece, rectangular coils.
► Materials and process developed for maximum performance, minimum quantities.
► High axial and radial fill factors minimize conductor and core costs, maximize short circuit strength.
► Precise dimensional control during winding and finishing to minimize core/coil clearances.
AMT Core/Coil Assembly
► Ribbon groups overlapped.
► Groups staggered to space overlaps across joint.
► Joint is opened up for core/coil assembly and then re-laced.
► Joint can be opened and closed multiple times.
► Allows transformers to be repaired if necessary.
► One piece core allows for easy assembly.