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Modeling, Design, and Control of Solid-State Transformer for Grid Integration of Renewable Sources
Published in Md. Rabiul Islam, Md. Rakibuzzaman Shah, Mohd Hasan Ali, Emerging Power Converters for Renewable Energy and Electric Vehicles, 2021
Md. Ashib Rahman, Md. Rabiul Islam, Kashem M. Muttaqi, Danny Sutanto
For the manufacturing of the traditional distribution transformer core, the silicon steel (Fe97Si3, Fe93.5Si6.5) and ferrite (MnZn, NiZn) have been extensively adopted [5]. The silicon steel material has the highest magnetic flux density (2.0 T); however, it has higher core loss property. The soft ferrite material has low specific flux density (0.26–0.55 T) which results in an increased size of the HFML. The amorphous (Fe76(SiB)24, Co73(SiB)27) magnetic material has comparable flux density (1.56 T) and shows high power loss at higher frequencies [21]. The nanocrystalline (FeCuNbSiB) magnetic material has lowest core loss and comparable flux density (1.23–1.45 T) [5] and therefore, it is the most suitable candidate in terms of flux density and core loss for the development of energy-efficient, compact SST. It is to be noted that the cost of the nanocrystalline material is comparatively high in comparison to the other existing magnetic materials.
Nanotechnology for Electrical Transformers
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
J.E. Contreras, E.A. Rodríguez
The magnetic core of an electrical transformer is typically formed by lamination stacks of iron–silicon alloy, and it has the aim to provide a low reluctance path for the magnetic flux linking primary and secondary windings [12]. Silicon steel has been used to build transformer cores, since silicon reduces the hysteresis loss and increases both permeability and resistivity of the material, however, its concentration must be limited to about 4.5% to prevent the steel becomes brittle and hard. Nowadays, grain-orientated electrical steels, which have extremely high magnetic properties in the rolling direction, are indispensable for achieving high effciency in electrical transformers [73]. New technologies have been also considered and introduced to reduce core losses in transformers, such as mechanical and laser-scribed silicon steel. On the other hand, innovative amorphous materials, which are alloy ribbons with a noncrystalline structure produced by ultrarapid quenching (106°C/s approx.), have successfully implemented in distribution transformers cores to achieve good effciency, since amorphous transformers have very low no-load losses than conventional transformers [74].
External Corrosion Protection
Published in Mavis Sika Okyere, Corrosion Protection for the Oil and Gas Industry, 2019
The role of the winding: The transformer winding constitutes the internal circuit of the device; it is directly connected to the external grid and is the most important component of the transformer, often called the “heart” of the transformer. The change in the number of winding turns can change the voltage. When the winding is assembled with the core, it is both wound into the transformer itself and constitutes an electromagnetic induction system to obtain the required voltage and current. Silicon steel sheets are widely used in medium- and low-frequency transformers and motor cores, especially power frequency transformers. Because silicon steel itself is a kind of material with strong magnetic permeability, it can generate large magnetic induction intensity in the energized coil, which can make the transformer volume smaller and improve the working efficiency of the transformer.
Performance improvement and microstructure evolution of powder metallurgy high silicon steel with phosphorus addition
Published in Powder Metallurgy, 2023
Qian Qin, Fang Yang, Cunguang Chen, Junjie Hao, Zhimeng Guo
Silicon steel sheets with high silicon content have a wide application range in high-frequency motors, audio and high-frequency transformers, magnetic shielding and other magnetic equipment [1]. In general, with the increase of silicon content in silicon steel sheet, the resistivity and magnetic permeability increase, while the coercivity and magnetostriction coefficient reduce, and the eddy current loss and hysteresis loss decrease [1–3]. When the silicon content increases to 6.5 wt-%, the magnetostriction approaches zero, the iron loss (especially at high frequency) is greatly reduced, and the magnetic permeability reaches the maximum value [4,5]. However, its saturation magnetisation and processing performance will be significantly reduced, which will adversely affect the lightweight and large-scale production of high-silicon steel [6,7]. Reducing a certain amount of Si content and adding other beneficial elements are worth trying to improve the silicon steel system, thus achieving the dual optimisation of magnetic properties and processing properties.
Magnetic performance and microstructure characterisation of powder metallurgy Fe–6.5 wt-% Si high-silicon steel
Published in Powder Metallurgy, 2022
Qian Qin, Guangbang Li, Fang Yang, Pei Li, Cunguang Chen, Junjie Hao, Zhimeng Guo
High-silicon steel (Fe–6.5 wt-% Si), containing about 6.5 wt-% silicon content, has a wide application range in magnetic devices, such as high-frequency motors, audio frequency and high-frequency transformers, and magnetic shielding, due to its high electrical resistivity, very low magnetostriction and low magnetocrystalline anisotropy. It can effectively reduce iron loss and improve work efficiency [1–3]. In general, it is hard and brittle at room temperature as a result of the existence of two ordered phases, B2 and D03. Therefore, it is difficult in achieving preparation by the conventional cold rolling method, which restricts its production and application [4,5].
Deformation characteristics and grain size effect of thin silicon steel sheet during shearing
Published in Machining Science and Technology, 2020
Yiwei Zhu, Qiusheng Yan, Jiabin Lu
Magnetically soft silicon electrical steel (electrical, or silicon steel for short) is a ferrosilicon alloy with a low carbon content, which is an indispensable magnetically soft alloy in electrical power systems, electrical engineering, and the electrical industry: it is mainly used as iron core of various motors, generators, and transformers. In iron core material, grain boundaries can delay the movement of magnetic domain walls, leading to a loss of magnetic hysteresis. For this reason, the grain size of SSS is generally large. Especially, the oriented SSS can exhibit millimeter-sized grains and the thickness of steel sheets is only equivalent to the size of a grain. Thus, silicon steel sheet (SSS) has developed to be ultra-thin (Kubota et al., 2000). Generally, the thickness of common non-oriented SSS shows the lowest specification of 0.15 mm while the lowest thickness of common oriented SSS is 0.10 mm. Owing to the eddy-current loss of an iron core being positively proportional to the square of the thickness of a steel sheet, reducing the thickness of the steel sheet can effectively reduce eddy-current loss. Decreasing the thickness of the steel sheet does not reduce saturation magnetization, so it is a common method for limiting high-frequency iron loss. With the development of motors to higher speeds and frequencies of operation, this tendency toward thickness-reduction of SSS has been shown in various industries including household appliances, electric automobiles, and aerospace applications (Zhang et al., 2012). Some silicon steel sheets, such as non-oriented SSS with a thickness of 0.15–0.20 mm for special uses have been used in medium- and high-frequency motors (Kubota et al., 2000), while some oriented SSSs with the thickness of 0.025–0.10 mm have been applied in high-frequency transformers and pulse transformers (Kubota, 2005).