Research on electromagnetic efficiency optimization in the design of air-core coils

IEEJ Transactions Elec Engng

Wang³

et al. 2018

Self Cite

In this paper, a fluid‐thermal coupled finite element model is established to calculate the temperature rise of a dry type air‐core reactor, and it accuracy is verified by the experimental results obtained from a prototype. Taking the initial design parameters based on the equal height and the thermal flux design method, the detailed temperature field of the reactor is obtained both with and without the rain cover. It is shown that the maximum temperature rise of the inner encapsulations is different and higher after adding the rain cover. The reasons are given by analyzing the changes of the fluid velocity in the air ducts. In order to realize the same temperature rise and not more than the limit after adding the rain cover, two parameters of the rain cover are considered, which have five levels. The performance statistics analysis and optimal structure parameters of the rain cover are achieved. Meanwhile, a heat load optimization method is proposed for the inner encapsulations, and its correctness is validated by the temperature field simulation results. This is of great significance in guiding the thermal optimization of the reactor with rain cover. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Δ T_{\max} = \frac{2 q_{w} H}{du ρ c_{p}} + \sqrt{\frac{48 q_{w} italicH υ}{ρ italicg β d^{3} c_{p}}}

The average fluid velocity u in air ducts can be calculated according to :

u = \sqrt{g β {dq}_{w} false/ ((), 12 μ c_{p})}

where μ is the dynamic viscosity of the fluid in air ducts.…”

Section: Thermal Optimization Of the Reactor With The Rain Covermentioning

confidence: 99%

Section: Heat Load Optimizationmentioning

confidence: 99%

See 1 more Smart Citation

Thermal optimization for nature convection cooling performance of air core reactor with the rain cover

IEEJ Transactions Elec Engng

Wang³

et al. 2018

Self Cite

“…In Refs , the design method combined with thermal and electromagnetic optimization is proposed, to realize the minimum use of the metal conductor, but the encapsulation number is not considered, which directly affects the electromagnetic efficiency and thermal efficiency of the reactor and limits the optimization results. Thus, the encapsulation number should be taken into account in the optimization design of the reactor.…”

Section: Introductionmentioning

confidence: 99%

Research of electromagnetic and thermal optimization design on air core reactor

IEEJ Transactions Elec Engng

Wang³

et al. 2018

Self Cite

In this paper, the geometry-electromagnetic character, thermal condition of the coils, and encapsulation number are coupled in the optimization design of an air core reactor, to realize the minimum usage of metal conductor. Combined with the equality constraint conditions for maximum temperature rise conservation, inductance conservation, and structure function of the reactor, the optimization design curves and results are achieved based on the initial design parameters. According to the design results, the temperature field simulation model of the reactor is established, and the results verify the correctness of the optimization method. Compared with the design method of 'equal height and heat flux' and thermal-electromagnetic character without considering the change of encapsulation number, the proportionality factor of metal conductor usage is 0.73 with the optimization method. It shows that the optimization method can significantly improve the utilization ratio of the conductor. Meanwhile, the influence of regularity on the electromagnetic efficiency, thermal efficiency, and other parameters is also obtained.

“…In [14,15], the thermal and electromagnetic optimization are combined in the design of the reactor, however, the change of the air duct width and encapsulation number are not simultaneously considered, which directly affects the electromagnetic and thermal characteristics of the reactor, and eventually lead to the results that the design parameters not being optimal. Thus, the air duct width and encapsulation number should be taken into account.…”

Section: Introductionmentioning

confidence: 99%

Thermal and Electromagnetic Combined Optimization Design of Dry Type Air Core Reactor

Chen

et al. 2017

Energies

Self Cite

Abstract:In this paper, taking the minimum metal conductor usage of an air core reactor as optimization goal, the influence of air ducts width and encapsulation number on thermal efficiency and electromagnetic efficiency are analyzed. Combined with the equation constraint conditions for maximum temperature rise conservation, inductance conservation and structure function of reactor considering the change of air ducts width and encapsulation number, the thermal and electromagnetic combined optimization curves are formed, and design results are achieved based on the initial design parameters. Meanwhile, the temperature field simulation model of the reactor is established and the results verify the correctness of the optimization method. According to the design results, the proportionality factor of metal conductor usage is only 0.61 compared with the initial design parameters of the reactor, which shows that the proposed comprehensive optimization method can significantly reduce conductor usage, improving the metal conductor utilization ratio.