Tri-level half-bridge single-stage inverter and control method

Abstract

The invention provides a three-level half-bridge single-stage inverter and a control method thereof, belonging to the inverter field. One passage of voltage output circuit of the inverter consists of a power (V in ), two capacitors (C11 and C12), six power switch tubes (S1-S4, S9 and S10), two clamping diodes (D1 and D2), a transformer (T1), a filter inductor (L f1 ) and a filter capacitor (C f1 ), and another passage of voltage output circuit of the inverter consists of a power (V in ), two capacitors (C21 and C22), six power switch tubes (S5-S8, S11 and S12), two clamping diodes (D3 and D4), a transformer (T2), a filter inductor (L f2 ) and a filter capacitor (C f2 ). The inverter is formed by the differential combination of two three-level half-bridge DC converters with bidirectional power currents; the switch tube has low voltage stress and is suitable for high-voltage input sites; the load adaptability is strong and the dynamical performance is excellent. The three-level half-bridge single-stage inverter has two control methods as follows: a no-bias voltage semi-period working mode with two passages of inverters work in a half period respectively and a bias voltage full-period working mode with two passages of inverters work at the same time.

Description

technical field [0001] The invention relates to a three-level half-bridge single-stage inverter and a control method, belonging to the inverter in the field of power electronics. Background technique [0002] The widely used inverter is a static converter device that uses power semiconductor devices to convert direct current into alternating current for use with alternating current loads. The input and output electrical isolation of the traditional inverter technology uses a power frequency transformer, which has been gradually eliminated due to the shortcomings of large noise, bulkiness, and large output filter inductance, while the output AC load and the input DC power supply are isolated by a high-frequency transformer with a frequency above 20kHz The inverter is called a high-frequency link inverter. The volume, weight and audio noise of the high-frequency link inverter are greatly reduced, and the shortcomings of the low-frequency link inverter are overcome. It will re...

AI Technical Summary

Problems solved by technology

The capacity of the single-stage flyback inverter is small, the quality of the output voltage waveform is not high, and the application occasions are limited

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