阅读说明：本技术 一种基于零电流开关pwm变换器的三相电压整流器 (three-phase voltage rectifier based on zero-current switch PWM converter ) 是由 颜景斌 李航天 刘明亮 于 2019-11-26 设计创作，主要内容包括：本发明涉及电力电子领域,具体是一种以零电流转换作为软开关的新型三相电压整流器。该整流器包括：三相不可控整流桥、上下各串接一个DC-DC Buck斩波器、一个有源三次谐波电流注入网络、两个快速可关断开关管(T+和T)以及两个零电流开关PWM变换器单元。整流器的三相交流输入电源取自电网对称三相电,通过滤波器后再接三相不可控整流桥。本发明是一种单向、降压、带有功率因数校正功能的新型三相DC-DC整流器。与传统的整流器相比它具有单位功率因数运行,开关损耗小,输入电流谐波率低,全电压可调等优异性能。(The invention relates to the field of power electronics, in particular to novel three-phase voltage rectifiers using zero current conversion as soft switches, which comprise three-phase uncontrollable rectifier bridges, DC-DC Buck choppers which are respectively connected in series from top to bottom, active third harmonic current injection networks, two fast turn-off switching tubes (T + and T) and two zero current switch PWM converter units.)

The three-phase voltage rectifier based on the zero-current switch PWM converter is characterized by comprising a power grid symmetrical three-phase power, an LC filter circuit, a three-phase uncontrollable rectifier bridge, an active third harmonic injection circuit network, a DC-DC Buck chopper, two fast turn-off switching tubes, two zero-current switch PWM converter units and an output loop.

2. A three-phase uncontrollable rectifier bridge is connected with DC-DC Buck choppers respectively from top to bottom, active third harmonic injection networks are additionally arranged, a three-phase alternating current input power supply of a rectifier is taken from symmetrical three-phase power of a power grid, the three-phase uncontrollable rectifier bridge passes through a filter and then is connected with the three-phase uncontrollable rectifier bridge, three groups of harmonic injection networks are connected in parallel in the middle, harmonic current injection is controlled through a switch tube (T + and T-), and current fluctuation in the switching-on and switching-off processes of the switch tube (T + and T-) is reduced by two zero-current switch.

3. The LC filter circuit according to claim 1, wherein said LC filter circuit is composed of three filter inductors La, Lb, LC and three filter capacitors Ca, Cb, Cc, which are then connected to the grid symmetric three-phase power supply respectively.

4. The three-phase uncontrollable rectifier bridge as claimed in claim 1, wherein the three-phase uncontrollable rectifier bridge is composed of diodes D1, D2, D3, D4, D5, D6 and switching tubes T + and T-.

5. Wherein D1 and D2, D3 and D4, D5 and D6 are connected in series and then connected in parallel, and switching tubes T + and T-are respectively connected at the upper and lower ends

The active third harmonic injection network of claim 1 wherein the third harmonic injection network Sy1 is connected to diodes Dy1 and Dy2 in phase a, the third harmonic injection network Sy2 is connected to diodes Dy3 and Dy4 is connected to phase b, and the third harmonic injection network Sy3 is connected to diodes Dy5 and Dy6 in phase c.

The zero current switching PWM converter unit of claim 1, wherein said leading current switching PWM converter unit is constructed by forming auxiliary switches S1 and S2 by MOSFETs to short-circuit resonant inductors Lr1 and Lr2, and simultaneously forming a switching unit by connecting resonant capacitors Cr1 and Cr2 in series with auxiliary switches S3 and S4, so that periodically turning off Cr eliminates resonance between Lr and Cr to generate resonance only at the instant of switching transition, thereby creating a zero current switching condition for the power switch.

Technical Field

The invention relates to the field of power electronics, in particular to novel three-phase voltage rectifiers taking zero current conversion as a soft switch.

Background

With the rapid development of industrial technology, people have higher and higher quality requirements on used electric energy, and nowadays when energy is in crisis, power electronic devices characterized by high efficiency, energy conservation, high quality and reasonable use of electric energy are unprecedented, the use of power electronic equipment is quite extensive, and the power electronic equipment is indispensable both for small families and large countries.

Therefore, it is very important to find new rectifier topologies, where the switching loss of the rectifier and the switching frequency are in a linear relationship, and the switching loss increases with the increase of the switching frequency, and at this time, a soft switching technique is required to reduce the switching loss and reduce the harmonic waves to improve the power quality, and the zero-current switching PWM converter is soft switches which are applied to cycles.

Disclosure of Invention

In order to solve the problems, the invention provides three-phase voltage rectifiers based on a zero-current switch PWM converter, the rectifier circuit has the characteristics of lower device voltage stress, wide-range step-down output, stronger input and output current control capability, high-frequency and high-efficiency transmission and full load, and meanwhile, because the zero-current switch PWM converter is used as a soft switch, the switching loss is greatly reduced under the condition of not increasing the conduction loss.

three-phase voltage rectifier based on zero current switch PWM converter, including 6 diodes formed rectifier bridge, input filter circuit, 6 diodes and 6 IGBT composed harmonic injection circuit, and two zero current switch PWM converter switch units, characterized by that its basic circuit is three-phase Buck type PFC rectification circuit, in which the filter circuit is LC type filter circuit, its capacitor common end is grounded, the rectifier bridge and harmonic injection circuit together form the input voltage selection part, which is a parallel three-phase bridge arm, each phase bridge arm includes two series-connected diodes and bridge arm midpoint side series-connected two different direction with low forward voltage drop IGBT as switch tube T + and T-, then series-connected RLC output circuit, another side connected with three-phase voltage source through input filter circuit, the switch unit of the switch PWM converter is parallel-connected diodes on the switch tube and then series-connected resonance inductors, switch units on the Buck circuit diodes to complete the zero current switch off of switch tube T-and T +.