Multi-mode switching wide output direct current converter and switching control thereof

Abstract

The multi-mode switching wide output direct current converter comprises a coupling inductance circuit, an interleaving parallel circuit, a clamping capacitor, a resonant cavity, a transformer, a rectifier and an output capacitor, and the output voltage is controlled by adjusting the duty ratios of S1, S2, S3 and S4. The multi-mode switching wide output direct current converter can work in three modes, namely a high gain (HG) mode, a medium gain (MG) mode and a low gain (LG) mode. In different modes, the coupling inductance circuit not only plays a role of a filter inductor, but also plays a role of a transformer, so that the power density is improved, meanwhile, the direct-current converter can realize zero-voltage switching of all switching tubes in a wide input working range in an HG mode and an MG mode, the switching loss is effectively reduced, and the conversion efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of switching converters, in particular to a method for realizing wide-range operation of a DC converter in the technical field of power electronics. Background technique [0002] With the rapid development of complex applications such as renewable energy power generation, hybrid electric vehicles, and submarine cable observation stations, the demand for high-efficiency power conversion in a wide range is becoming more and more urgent. Wide voltage gain DC converters have become an integral part of such converters. High efficiency, high power density, wide voltage gain, low cost, and stable and reliable operation are key requirements for such converters. In addition, special requirements such as low current ripple are even key technical indicators for submarine cable observation stations. [0003] The LLC resonant converter has the characteristics of zero-voltage turn-on of the main power tube and high powe...

AI Technical Summary

Problems solved by technology

[0003] The LLC resonant converter has the characteristics of zero-voltage turn-on of the main power tube and high power density, and has been widely used in high-efficiency power converters. However, when the traditional LLC resonant converter is applied to a wide range of ) or pulse width modulation (PWM) control methods face the frequency range is too wide, and ZVS is difficult to achieve under light load conditions, large reactive power circulation reduces the efficiency of the converter, can not meet the application requirements of a wider operating range

[0004] Moreover, in the traditional voltage-type DC converter, the voltage stress of the switching tube is relatively fixed, and the output voltage control is intuitive, but a short-circuit protection circuit with a fast action time is required, and the input current ripple is large, which is not suitable for submarine cable observation stations and other requirements. Where the equipment has a long service life

Images