High-frequency distribution transformer

Abstract

The invention discloses a high-frequency distribution transformer, which comprises a three-phase voltage high-frequency modulation circuit, high-frequency phase-shifting transformer, a multi-pulse rectifying circuit, and an inverter output module, wherein each phase of bridge arm of the three-phase voltage high-frequency modulation circuit comprises n serially-connected single-phase rectifying modules and inverter modules of which the number is m times of that of the single-phase rectifying modules. Output voltage of the high-frequency distribution transformer can be adjusted by adjusting the duty cycle of the inverter modules in three-phase voltage high-frequency modulation circuit; the operation of the high-frequency phase-shifting transformer in a high-frequency modulation mode can effectively reduce the volume and weight of the whole distribution transformer; and the distribution transformer can solve the flow equalization problem of the multi-pulse rectifying circuit, allows a power factor on the line side to be close to 1 and substantially eliminates the current harmonics on the line side. The high-frequency distribution transformer is applicable to the prior power frequency power distribution system and multiphase power distribution system as well as high-frequency power distribution system such as 400Hz ship power distribution system.

Description

technical field [0001] The invention relates to a high-frequency distribution transformer, which belongs to the technical field of power electronic power conversion. Background technique [0002] At present, the high-voltage side of the distribution transformer is mostly three-phase 10kV input, and the low-voltage side is 380V / 220V low-voltage three-phase four-wire system output. This type of distribution transformer has four disadvantages: (1) The power factor of the low-voltage side (that is, the load side) directly affects the high-voltage side, and the load with too low power factor must require power factor compensation; (2) The harmonics on the load side are all If it flows into the power grid, it will cause many harms, and harmonic compensation is required; (3) Factors such as three-phase imbalance, overload, and short-circuit faults on the load side will directly affect the power quality and reliability of the power grid. (4) Usually this type of power frequency dis...

AI Technical Summary

Problems solved by technology

This type of distribution transformer has four disadvantages: (1) The power factor of the low-voltage side (that is, the load side) directly affects the high-voltage side, and the load with too low power factor must require power factor compensation; (2) The harmonics on the load side are all If it flows into the power grid, it will cause many harms, and harmonic compensation is required; (3) Factors such as three-phase unbalance, overload, and short-circuit faults on the load side will directly affect the power quality and power supply reliability of the power grid

(4) Usually this type of power frequency distribution transformer is mostly oil-immersed, which has inherent disadvantages such as large volume, many materials, and flammability.

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