Fuji Electric Review
Vol.68-No.1,2022
Power Supply Systems Contributing to Stable Power Supply and Energy Saving
Power Supply Systems Contributing to Stable Power Supply and Energy Saving
Changes in the energy supply and demand environment due to the expanded use of renewable energy and advancements in social infrastructure and industrial systems through digital transformation (DX) have further increased the need for a stable supply of power and reliable operation of equipment at factories and other facilities. There are also growing needs for products to be eco-friendly and compact according to the internationally strengthened efforts to conserve the environment.
This special issue will introduce the base technologies for Fuji Electric’s competitive components (devices) to help achieve stable equipment operation, eco-friendliness (energy saving and environmental impact reduction) and product downsizing.
MITANI, Yasunori
KAWANO, Masashi; MATSUMOTO, Yasushi
Fuji Electric provides equipment and systems that help maintain stable power supply and facility operation and save energy. For power supply systems in data centers, we are offering our Comprehensive Electrical Equipment Proposals, which include extra high-voltage substation equipment, emergency power generation equipment, substation equipment, and UPS systems, on the basis of our extensive delivery experiences. While developing a local micro-grid technology and its applications, high-voltage, large-capacity transformers, gas-insulated switchgear (GIS), and industrial transformer rectifiers, we are meeting the challenges of supplying stable power with our power supply systems.
HAMADA, Ippei
In recent years, there has been an increase in the number of large-scale data centers (DCs) throughout the world as companies move information systems to the cloud and expand their use of e-commerce. This trend has also increased the demand for high capacity uninterruptible power systems (UPSs) capable of stabilizing the supply of power to the DCs. Fuji Electric, providing lineups of electrical equipment for power systems, has been promoting its Comprehensive Electrical Equipment Proposals that enhance supply reliability and economy. We have downsized our UPSs, which are key equipment of power systems, to reduce their footprints, migrated I/O-M functions to switchboards to shorten installation periods, and provided HE mode to save energy.
YASUMOTO, Koji; NEMOTO, Kenji; KITADANI, Yuji
The capacity of uninterruptible power systems (UPSs) has been expanding to meet the needs of larger data centers. Power systems with UPSs face various challenges, such as ensuring redundancy during maintenance, preventing erroneous operation, and suppressing voltage fluctuations during power supply switching and energizing of largecapacity transformers. The measures to build a power supply system with enhanced redundancy and maintainability include an N+2 system to ensure redundancy and sequence circuits using a rotation control key switch to prevent erroneous operation. In addition, inrush exciting current, a cause of voltage fluctuations, can be suppressed through the sequential closing of circuit breakers during a power supply switching and the replacement of two parallel high voltage transformers with a single high capacity transformer.
MURATSU, Hiroki; WAKABAYASHI, Fumiya; TOKUDA, Tsuyoshi
The need for supplying stable power to information equipment, such as servers is increasing as the use of cloud information systems and e-commerce are expanding. Fuji Electric has developed a static transfer system cabinet necessary for transferring in a 2N (duplex) system, a redundant configuration for power supply systems. It has a hybrid switch that uses mechanical switches and semiconductors switch together to speed up transferring, lower loss, and downsize the cabinet. It also deliver functions, such as accommodating a built-in bypass breaker for maintenance, supporting the redundancy of major components, and reducing the effect on the load when switching under UPS synchronization, to improve the reliability of power systems, contributing to stable power supply.
NAGATSUYU, Tomohiro; MIYATA, Tomokazu
Electrical facilities are being required to improve energy efficiency to reduce greenhouse gas emissions and achieve carbon neutrality. Meanwhile, data centers and semiconductor factories have recently become using larger capacity cast resin transformers (MOLTRA) to respond to rising power demand, however, also requiring downsizing. To meet this need, Fuji Electric has developed the “V-ECO MOLTRA,” rectangular large-capacity 5-leg type MOLTRA. It uses a 5-leg wound iron core whose core and coils are rectangular shaped. As a result, its height is 15% lower while maintaining the same energy-saving performance and footprint than that of the conventional product.
UEKUSA, Hideaki; YAMACHI, Toshifumi; SHIRAKURA, Yoshizumi
The electric power management system centrally manages the power system to feed power from railway substations and sectioning posts to trains and railroad stations. In addition to stable, continuous power supply, it is required to deliver the functions to improve the efficiency of the operation and maintenance of the power system including railway substations. Fuji Electric offers the electric power management system that meets these needs to enhance functionality such as failure recovery, improve screen visibility, and streamline the system configuration, contributing to safe and stable railway transportation.
WATABE, Kohei; OKAZAKI, Yohei; ASADA, Masato
Various types of industrial power supplies are used in material manufacturing equipment depending on the application. Among them, transformer rectifiers for aluminum smelting have large capacities more than several hundred MVA per unit, posing specific issues. To address the issues, Fuji Electric has adopted an optimum design based on various simulations and harmonic system analyses. As a result, we have downsized the transformer rectifier and improved its reliability by increasing analysis accuracy and optimized materials, confirmed the safety in an accident by simulating the short-circuit fault in the rectifier, and prevented power quality deterioration in the entire power supply system by analyzing the harmonics generated from the transformer rectifier.
KAWASAKI, Daisuke; TSUKUTA, Motohiro; TSUTSUI, Shigeo
The need to continue to supply electricity even in a power outage or power supply malfunction has been increasing the demand for medium-capacity uninterruptible power systems (UPSs) in factories and broadcasting facilities. The product line of medium-capacity UPSs need to include varied types to meet the specifications of individual load equipment. Also required are flexibly meeting the need for equipment replacement and predictive maintenance for stable operation. Fuji Electric has newly developed its “FX Series” medium-capacity UPSs to meet various needs for replacement by reducing their footprint and expanding the range of the battery voltage. A component failure diagnosis with abnormality symptom detection functions has allowed degraded parts to be replaced before failure, improving operational stability.
HIKOSAKA, Tomoyuki; CHIBA, Koichiro
Mineral oil, which has been used as the insulating oil in oil-filled transformers, has problems such as CO2 emission at the time of disposal and environmental pollution at the time of leakage. On the other hands, vegetable-based insulating oils suffer from a poor cooling effect and low oxidation stability. It is against this backdrop that Fuji Electric, in collaboration with Lion Corporation, developed a palm fatty acid ester (PFAE) with low kinematic viscosity and high oxidation stability through esterification, distillation and purification process of palm oil. Furthermore, Fuji Electric also developed a palm fatty acid ester filled transformer using the PFAE and confirmed that it possesses excellent insulating, cooling, and long-term stability properties. PFAE can be reused as diesel fuel without specific treatment when being disposed, and even if it leaks into the soil, the biodegradation reaction by microorganisms can reduce the impact on the environment.
OTSUBO, Tomonori; NAKANISHI, Toshikazu
The demand is increasing for vending machines that allow customers to purchase products without face-to-face interaction, as society seeks to prevent the spread of COVID-19. There is also a growing demand mainly among urban retailers to increase sales opportunities outside of store hours in limited spaces, such as storefronts. To meet these demands, Fuji Electric has developed and released “Multi-kun,” a spacesaving, compact multi-purpose vending machine that can be installed outdoors.