Design method of high-power medium-frequency power transformer

Abstract

The invention discloses a design method of a high-power medium-frequency power transformer. The design method comprises the following steps: deriving a single-strand optimal diameter dstr-opt and a strand number expression k of a square litz wire; deriving a diso expression of a magnetic flux leakage channel of the medium-frequency power transformer adopting the square Litz wire, wherein the disoexpression is used for adjusting the leakage inductance L sigma (pri) of the transformer; based on the high-frequency square wave characteristic breakdown voltage of a turn-to-turn insulating materialof the medium-frequency power transformer, proposing a calculation method for the main insulation size and the longitudinal insulation size of the medium-frequency power transformer; deriving iron core high-frequency loss Pcore and square litz wire high-frequency loss expressions PHV and PLV under square wave voltage excitation; based on the derived expression, establishing a computer-aided optimization design method for the medium-frequency power transformer based on a non-dominated sorting genetic algorithm. Leakage inductance parameters can be accurately controlled, the power density and efficiency of the medium-frequency power transformer are improved, and the calculation amount and calculation time required by optimization design are reduced.

Description

technical field [0001] The invention belongs to the field of intermediate frequency transformer design, and in particular relates to a design method of a high-power intermediate frequency power transformer. Background technique [0002] The design process of low-voltage, small-capacity, and high-frequency transformers used in power electronic equipment such as inverters and switching power supplies is relatively mature. The relevant design is based on the core area product formula method, and the minimum value of AP is calculated. The corresponding core The size is also the minimum, so from a practical point of view, at least one larger core should be selected from the core product manual. For example, in a design example of a high-frequency transformer for a flyback switching power supply, when the core is selected by the AP method, the calculated AP is 0.48cm 4 , the AP of the actually selected iron core specification is 0.91cm 4 . The core area product formula also inv...

AI Technical Summary

Problems solved by technology

In 2013, the 100kVA three-phase PET prototype developed by the Institute of Electrical Engineering, Chinese Academy of Sciences was composed of a three-phase modular multilevel rectifier on the high-voltage side, an isolated DC-DC converter and a three-phase inverter on the low-voltage side, which reduced the number of intermediate frequency transformers, but about The design and implementation of intermediate frequency transformers are not reported in detail

Under high-frequency non-sinusoidal excitation, transformer capacity, temperature rise, operating frequency, iron core operating flux density, loss, iron core shape and winding arrangement are mutually restricted, forming a complex systematic design problem

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