How to reduce transformer losses?5 answersTo reduce transformer losses, various strategies can be implemented based on different research findings. One approach involves utilizing Path-core type resonant inductance adjustable (PRIA) transformers in high-frequency LLC resonant converters, which effectively reduce core losses and coil losses, thus improving efficiency. Another method is the use of horizontal wall shunts in converter transformers to decrease stray losses, enhancing the transformer's overall efficiency. Additionally, modifying the design of distribution transformers to operate efficiently during light loading conditions can help minimize losses occurring in such scenarios. Furthermore, implementing a novel topology like transformer auto stop-start can automatically manage transformer energization to reduce electric losses under varying load conditions. Lastly, optimizing transformer sizing based on historical load data can lead to significant reductions in core and copper losses, ultimately enhancing efficiency and achieving substantial energy savings.
How to do electric transformer calculations?5 answersTo perform electric transformer calculations, various methods and models can be utilized. One approach involves establishing a multi-field coupling calculation model using finite element analysis software like ANSYS to analyze electromagnetic vibration and noise in power transformers. Another method includes developing a mathematical model considering differential electromagnetic parameters and approximating the magnetic system of the transformer with a planar circuit. Additionally, a calculation method for a composite electric field of a converter transformer, considering temperature gradients, involves establishing fluid-temperature and electric field models, and analyzing the composite electric field under different temperature conditions. Furthermore, a transformer electromagnetic vibration noise calculating method based on the finite element method can be employed, which considers all noise influence factors and provides accurate results for vibration and noise analysis.
How to calculate parasitic parameters in high voltage high frequency transformer?3 answersParasitic parameters in high voltage high frequency transformers can be calculated using various methods proposed in the literature. One approach is to use an optimization method to extract the parasitic parameters of the transformer. This method involves substituting the traditional equivalent circuit with a five capacitance network equivalent circuit model that considers the characteristics of the electric field energy transformation and the common mode electromagnetic interference. Another analytical approach is based on the principle of electrostatic energy and calculates the self-capacitance of power transformers by considering the capacitance between the turns and between the layers. Additionally, a novel analytical method has been proposed for calculating turn-to-turn, turn-to-core, and stray capacitances in each winding, which can be used to calculate the equivalent parasitic capacitance in high-voltage switching transformers. These methods provide efficient ways to accurately calculate the parasitic parameters in high voltage high frequency transformers.
The HTS method is expensive?5 answersThe high temperature superconducting (HTS) method can be expensive. However, a computer-aided tuning method has been developed to accurately tune HTS filters with less time and cost. Additionally, the use of explicitly testable models in the design of material handling systems can substantially reduce software costs. Single crystal dielectrics, which are desirable in cellular and satellite communications, can be expensive. However, by improving the ceramic processing and sintering conditions, high quality dielectric resonators can be produced at a lower cost. Furthermore, the use of commercially available high-temperature superconductor tape as a starting current limiter for induction motors offers reduced current waveform distortion and lower harmonic pollution during startup. In summary, while the HTS method and certain components can be expensive, there are methods and techniques available to mitigate costs and improve efficiency.
How is the ring current loss modeled in SWMF?5 answersThe ring current loss in the SWMF model is modeled by incorporating different ionospheric conductance and electron loss models. The Chen and Schulz electron loss model, which includes strong diffusion in the plasma sheet and weak diffusion in the plasmasphere, is used to enhance the equatorial electron pressure in the inner magnetosphere during stormtime. This model takes into account the effects of electron losses on the electron pressures and the magnetospheric-ionospheric coupling, which in turn affects the proton transport in the ring current. The simulations using this model have been able to reproduce features observed by in situ magnetic field and proton flux data, as well as TWINS global ENA observations. It is important to incorporate realistic descriptions of ionospheric conductance and electron losses in inner magnetospheric models to accurately simulate ring current dynamics.
How can we calculate the inductance curve of a coil?5 answersThe inductance curve of a coil can be calculated using various methods. One approach is to use an analytical algorithm based on Biot-Savart's law, which allows for the fast calculation of coil inductance. This algorithm has been verified and shown to have good agreement with measured results. Another method involves an algorithmic solution based on the law of Biot-Savart, which calculates the spatial magnetic flux density of arbitrarily shaped current paths. By discretizing the coil and its confined volume, the magnetic flux and resulting self-inductance can be determined. Additionally, experiments with inductance coils can be performed using a data-acquisition system, which can provide convenient and informative measurements. A simple method for calculating the mutual and self inductances of circular coils of rectangular cross section and parallel axes has also been presented, which involves one-dimensional integrals and can be evaluated numerically. Finally, a computer data storing program can be used to control a data receiver circuit and measure the inductance of a coil.