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Ocean and Geothermal Energy Systems
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| Pengarang | : | Annette von Jouanne |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 105 (No. 11) |
| Halaman | : | 2147-2165 |
| Abstrak | : | This paper presents techno-economic summaries of ocean wave, tidal and current, ocean thermal, and geothermal energy, including grid interface characteristics. These forms of energy represent a significant opportunity to complement diversified energy conversion portfolios. Ocean wave energy conversion relies on the capture of kinetic and potential energy in moving and elevated water in an ocean wave. Tidal and current technology converts the kinetic energy in moving water, much like a wind turbine. Ocean thermal converts the energy available in the temperature gradient of warm surface water and cold deep water. Last, geothermal conversion utilizes the hot rock and water deep within the Earth. The total global average wave resource is estimated at approximately 2000 GW, with approximately 300 GW in the United States. The total global tidal resource is estimated at approximately 1000 GW, with 50 GW in the United States. The marine current resource estimate for the Florida Current in the southeast United States is estimated at 5 GW. Ocean thermal has a global capacity estimate of 5000 GW. Last, the global conventional hydrothermal geothermal capacity estimate is approximately 200 GW, but with much more possible through enhanced geothermal systems. For cost, it was found that the long-term projected wave energy conversion cost is 0.10−0.15/kWh.Thelong−termprojectedtidalcostisfoundtobe0.025-0.25/kWh. Ocean thermal long-term cost is projected at 0.10−0.18/kWh.Andlast,geothermal,beingmorecloselyalignedwithtraditionalthermalgeneration,isestimatedat0.03/kWh to $0.15/kWh. |
Deployable Techniques for Small Satellites
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 106 (No. 3) |
| Halaman | : | 471-483 |
| Abstrak | : | A deployable structure serves an important function in small satellites as their performance is improved steadily. Larger deployable solar array paddles are expected as the satellite requires a larger amount of electric power. The synthetic aperture radar (SAR) system for small satellites requires a deployable antenna. Various deployable membrane structures have been proposed for the deorbit of micro/nanosatellites in low Earth orbit. The actuators and devices for a deployable structure continue to progress along with the development of a deployable structure. The hold-release mechanism has been becoming smaller and simpler. The shape control devices are actively researched for a high-precision deployable structure. There are several requirements imposed on the deployable structures, e.g., low cost, lightweight, small volume in stored configuration, reliable deployment, large aperture in deployed configuration, and accuracy/repeatability of a deployed shape. Dedicated efforts are made to satisfy these requirements in research and development of a deployable structure/device. This paper provides an overview of the past and current research and development of a deployable structure for small satellites. |
Solar Photovoltaic and Thermal Energy Systems: Current Technology and Future Trends
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 105 (No. 11) |
| Halaman | : | 2132-2146 |
| Abstrak | : | Solar systems have become very competitive solutions for residential, commercial, and industrial applications for both standalone and grid connected operations. This paper presents an overview of the current status and future perspectives of solar energy (mainly photovoltaic) technology and the required conversion systems. The focus in the paper is put on the current technology, installations challenges, and future expectations. Various aspects related to the global solar market, the photovoltaic (PV) modules cost and technology, and the power electronics converter systems are addressed. Research trends and recommendations for each of the PV system sectors are also discussed. |
Wind Energy Systems
| Pengarang | : | Frede Blaabjerg |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 105 (No. 11) |
| Halaman | : | 2116-2131 |
| Abstrak | : | Wind power now represents a major and growing source of renewable energy. Large wind turbines (with capacities of up to 6–8 MW) are widely installed in power distribution networks. Increasing numbers of onshore and offshore wind farms, acting as power plants, are connected directly to power transmission networks at the scale of hundreds of megawatts. As its level of grid penetration has begun to increase dramatically, wind power is starting to have a significant impact on the operation of the modern grid system. Advanced power electronics technologies are being introduced to improve the characteristics of the wind turbines, and make them more suitable for integration into the power grid. Meanwhile, there are some emerging challenges that still need to be addressed. This paper provides an overview and discusses some trends in the power electronics technologies used for wind power generation. First, the state-of-the-art technology and global market are generally discussed. Several important wind turbine concepts are discussed, along with power electronics solutions either for individual wind turbines or for entire wind farms. Some technology challenges and future solutions for power electronics in wind turbine systems are also addressed. |
Flexible AC Transmission Systems (FACTS) and Resilient AC Distribution Systems (RACDS) in Smart Grid
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 105 (No. 11) |
| Halaman | : | 2099-2115 |
| Abstrak | : | Transmission and distribution (T&D) networks are a critical part of the power grid. As moving towards a smart-grid, it is essential to modernize the T&D networks and make it “Smart-grid ready”. The concept of flexible ac transmission systems (FACTS) has been well-known for three decades. Rapid advancements in power electronics technology in the past decades have led to a new generation of FACTS devices. The Modern FACTS technology helps the transition of transmission networks to “smart”. With increasing penetration of distributed generation, the distribution network is seeing unprecedented variation in terms of its fundamental operation and control, from renewable energy integration to microgrid, from active control of power quality, volt/var and frequency to self-healing and islanding operation. As a key part of smart-grid at the distribution level, we summarize the current efforts as a concept of resilient ac distribution systems (RACDS). The concepts of both FACTS and RACDS for a smart grid are introduced in this paper. Different configurations, key benefits, operating principles and world-wide installations of FACTS and RACDS devices are presented in detail. The ongoing and future direction of R&D leading to newer generations of FACTS and RACDS are also discussed. |
Onboard Processing With Hybrid and Reconfigurable Computing on Small Satellites
| Pengarang | : | Alan D. George |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 106 (No. 3) |
| Halaman | : | 458-470 |
| Abstrak | : | Due to the increasing demands of onboard sensor and autonomous processing, one of the principal needs and challenges for future spacecraft is onboard computing. Space computers must provide high performance and reliability (which are often at odds), using limited resources (power, size, weight, and cost), in an extremely harsh environment (due to radiation, temperature, vacuum, and vibration). As spacecraft shrink in size, while assuming a growing role for science and defense missions, the challenges for space computing become particularly acute. For example, processing capabilities on CubeSats (smaller class of SmallSats) have been extremely limited to date, often featuring microcontrollers with performance and reliability barely sufficient to operate the vehicle let alone support various sensor and autonomous applications. This article surveys the challenges and opportunities of onboard computers for small satellites (SmallSats) and focuses upon new concepts, methods, and technologies that are revolutionizing their capabilities, in terms of two guiding themes: hybrid computing and reconfigurable computing. These innovations are of particular need and value to CubeSats and other Smallsats. With new technologies, such as CHREC Space Processor (CSP), we demonstrate how system designers can exploit hybrid and reconfigurable computing on SmallSats to harness these advantages for a variety of purposes, and we highlight several recent missions by NASA and industry that feature these principles and technologies. |
HVDC Systems in Smart Grids
| Pengarang | : | Mike Barnes |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 105 (No. 11) |
| Halaman | : | 2082-2098 |
| Abstrak | : | The use of direct current (dc) power networks, either at high voltage or at medium voltage, is being increasingly seen in modern smart grids. This is due to the flexible control possible with dc and its ability to transmit and distribute power under circumstances where alternating current (ac) networks are either unable to, or less economic. This paper provides an overview of the evolution of high-voltage dc (HVDC) transmission from early Thury systems, to modern ultrahigh-voltage dc and multiterminal voltage-source converter systems. The operation of both current-source and voltage-source systems is discussed, along with modeling requirements. The paper provides a snapshot of the state of the art of HVDC with copious references to enable in-depth reading. Key developments over the last 20 years are highlighted. Issues surrounding multiterminal operation and dc protection are explained, along with drivers in economics and policy. This will inform HVDC integration into smart grids. |
Multilevel Converters: Control and Modulation Techniques for Their Operation and Industrial Applications
| Pengarang | : | J. Panglaykim. |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 105 (No. 11) |
| Halaman | : | 2066-2081 |
| Abstrak | : | In the last decades, multilevel converters have been developed usually for medium-voltage high-power applications. They have become a mature solution for the increasing power demand of multiple applications such as renewable energy systems, power quality improvement, and motor drives. In this paper, the operation of multilevel converters is addressed focusing on control and modulation techniques for different well-known applications. The new developments are presented as an extension of conventional methods for two-level voltage-source converters which are still the mainstream solution for most cases. |
Multilevel Converters: Fundamental Circuits and Systems
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 105 (No. 11) |
| Halaman | : | 2048-2065 |
| Abstrak | : | This paper provides a chronological overview of the topology for multilevel converters, and discusses their different terminology usages and characteristics. The multilevel converters include three-level neutral-point-clamped (NPC) and neutral-point-piloted (NPP) inverters, three-level and four-level flying-capacitor (FLC) inverters, and a family of modular multilevel cascade converters. Some have already been put into commercial use, some have been on a research and development stage, and others have been on an academic research stage. This paper pays much attention to six family members of the modular multilevel cascade converters, intended for grid-tied applications and medium-voltage high-power motor drives. |
Power Semiconductor Devices for Smart Grid and Renewable Energy Systems
| Pengarang | : | Alex Q. Huang |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 105 (No. 11) |
| Halaman | : | 2019-2047 |
| Abstrak | : | Modern civilization is related to the increased use of electric energy for industry production, human mobility, and comfortable living. Highly efficient and reliable power electronic systems, which convert and process electric energy from one form to the other, are critical for smart grid and renewable energy systems. The power semiconductor device, as the cornerstone technology in a power electronics system, plays a pivotal role in determining the system efficiency, size, and cost. Starting from the invention and commercialization of silicon bipolar junction transistor 60 years ago, a whole array of silicon power semiconductor devices have been developed and commercialized. These devices enable power electronics systems to reach ultrahigh efficiency and high-power capacity needed for various smart grid and renewable energy system applications such as photovoltaic (PV), wind, energy storage, electric vehicle (EV), flexible ac transmission system (FACTS), and high voltage dc (HVDC) transmission. In the last two decades, newer generations of power semiconductor devices based on wide bandgap (WBG) materials, such as SiC and GaN, were developed and commercialized further pushing the boundary of power semiconductor devices to higher voltages, higher frequencies, and higher temperatures. This paper reviews some of the major power semiconductor devices technologies and their potential impacts and roadmaps. |