Loss calculation method for high-frequency high-power three-phase transformer

Abstract

The invention discloses a loss calculation method for a high-frequency high-power three-phase transformer, and the method comprises the steps: deducing an expression of the amplitude of each-order harmonic current component of the winding current iLA of the high-frequency three-phase transformer in a Y-Y-type, Y-delta type and delta-delta type winding connection mode; calculating primary and secondary winding alternating-current resistance under each order harmonic frequency; summing the losses corresponding to the harmonic current of each order to obtain a loss expression Pwp of the primary winding of the flat copper wire and a loss expression Pws of the secondary winding of the flat copper wire; deriving expressions of magnetic flux densities BY (t) and B delta (t) of the iron core; superposing the magnetic flux density waveforms generated by the primary winding and the secondary winding under the phase shift control to obtain the magnetic flux density B (t) waveform of the iron coreunder the load operation condition; and calculating the iron core loss of the high-frequency three-phase transformer in a Y-Y-type winding connection mode, a Y-delta type winding connection mode anda delta-delta type winding connection mode under the phase shift control operation condition. According to the method, the loss of the high-frequency high-power three-phase transformer is rapidly andaccurately predicted, and a foundation is laid for subsequent optimization design of the loss of the iron core of the high-frequency three-phase transformer.

Description

technical field [0001] The invention belongs to the field of high-frequency transformer loss prediction methods, and in particular relates to a high-frequency high-power three-phase transformer loss calculation method. Background technique [0002] Solid state transformers (solid state transformers, SSTs) are key components in future renewable energy transmission and management systems. The solid-state transformer SST consists of a rectifier on the input side, a DC conversion stage and an inverter for AC voltage output. Currently, a single-phase or three-phase isolated dual-active-bridge DC-DC converter (DAB-IBDC) suitable for high-power transmission and free flow of power in both directions has been proposed. Applied to the DC conversion stage of solid-state transformers. Compared with the single-phase DC / DC converter topology, the three-phase DC / DC converter has more advantages. It can not only greatly reduce the number of components such as high-frequency transformers, ...

AI Technical Summary

Problems solved by technology

The current waveform of the three-phase DC / DC converter is more complicated, which is related to factors such as winding connection mode and phase shift angle. The above method is no longer applicable.

The voltage waveform of the high-frequency three-phase transformer is related to the connection mode of the three-phase winding and the phase-shift control. sex is yet to be studied

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