一种新型高功率因数三相整流器的分析设计

分析了一种利用LC谐振来实现低输入电流谐波的三相不控整流器,它利用交流侧串联电感与整流桥上桥臂二极管的并联电容谐振来改善输入侧电流,电路结构较为简单.与传统的三相整流器相比,该整流器可显著降低输入电流的谐波含量,得到近似为1的高功率因数.详细分析了该整流器的工作原理和特性,并给出了参数设计方法及电路的优缺点.仿真和实验证明了结论的正确性.     

基于DSP+单片机的三相电压型PWM整流器控制系统设计

介绍了三相电压型PWM整流器主电路拓扑结构,重点分析了交流侧电感和直流侧电容对系统性能的影响。基于DSP+单片机双控制器设计了一种三相电压型PWM整流器控制系统,提出了一种交流侧电感和直流侧电容的设计方法,并确定了二者的取值范围。最后针对交流侧电流谐波含量和直流侧电压动态响应速度进行了相关实验。实验结果表明:整流器交流侧电流谐波含量较少,直流侧电压脉动较小,系统响应速度快,抗干扰能力强。验证了所述控制系统和设计方法的有效性。     

基于SVPWM的高功率因数三相混合开关型整流电路研究

提出一种高功率因数三相混合开关型SVPWM整流器,采用六脉冲晶闸管整流桥串联一个直流斩波环节的拓扑结构,分析其换流模式,利用SVPWM方法对输出恒定的直流电流进行控制,针对电网侧加入LC滤波环节而造成的网侧电压和电流相位不同步的问题,采取双闭环直接电流控制策略使网侧达到高功率因数,利用q轴电流给定不为零的方法来校正整流器的功率因数。仿真和实验波形验证了该整流器的优良工作性能,能够有效提高电能质量、实现网侧电流正弦化。     

近正弦输入电流三相整流器研究

分析了一种低输入电流谐波的三相不控整流器。它由输入电感、三相整流桥及其与整流二极管并联的电容组成,其结构简单。本文详细分析了该整流器的工作原理、特性、参数设计方法及适用场合。仿真和实验结果表明,该整流器与传统三相整流器相比,可显著降低输入电流的谐波含量,且在额定工作点附近可获得接近于1的功率因数。     

三相直流侧APF补偿性能的频域研究

三相不可控整流桥装置产生的电流谐波具有谐波含量大,谐波频谱分布宽的特点.直流侧有源电力滤波器是针对不可控整流桥装置提出的谐波治理方案.从频域角度分析直流侧有源电力滤波器电流环带宽与谐波补偿性能的关系,得到不同带宽所对应的补偿后电流THD理论数据,从而对三相直流侧有源电力滤波器的补偿性能进行定量的研究.通过该频域分析方法,将三相直流侧有源电力滤波器与传统交流侧有源电力滤波器进行对比分析.分析表明,在三相不可控整流桥带大电感负载情况下,当电流环带宽取1kHz时,直流侧有源电力滤波器补偿后电流THD为0.41%,交流侧有源电力滤波器补偿后电流THD为9.63%.采用平均电流控制策略,完成三相直流侧有源电力滤波器的设计.实验测试结果验证当电流环带宽取1kHz时,三相直流侧有源电力滤波器实现整流桥负载谐波电流的有效补偿.     

电流源型PWM整流器带容性负载的解耦控制方法

应用于不间断电源(UPS)时,三相电流源型整流器(CSR)因其直流输出端存在大电容而使得数学模型的阶数提高,增加了控制器的设计难度。针对带电容性负载的PWM型CSR建立了dq旋转坐标系中的数学模型,通过将d轴定向于交流滤波电容电压矢量,使得数学模型简化为相互解耦的直流侧和交流侧模型,进而可实现直流侧和交流侧的独立控制。进一步提出了在直流侧采用状态反馈控制来稳定直流母线电压,在交流侧引入虚拟阻抗进行网侧电流有源阻尼的控制方法,消除直流侧和交流侧之间由PWM调制过程所产生的相互影响,实现了直流侧和交流侧的解耦控制。基于40k V·A的UPS仿真和样机实验结果表明,该方法具有良好的动态性能和稳态性能。     

面向电流源型PWM整流器直流侧电压的多环路控制策略

三相电流源型PWM整流器作为低压直流配电系统有源前端时,因网侧LC滤波环节和直流侧电容的存在使系统控制难度增加.首先,在同步旋转坐标系下建立电压定向数学模型,通过控制网侧电流d轴与q轴分量,完成系统有功、无功功率的独立控制;其次,基于相量法提出一种电容电流补偿方法,仅构建电容电压前馈通道,实现间接电流控制策略下功率因数...     

电容电压反馈的电流型整流器有源阻尼控制研究

三相电流型PWM整流器在交流侧采用LC滤波器来滤除谐波,由于二阶LC滤波器的阻尼系数较小,容易引起网侧电流振荡。为此文中提出滤波电容电压反馈的有源阻尼控制,能够在不消耗有功功率的前提下,有效地滤除网侧电流谐波。通过仿真分析可知,提出的电容电压反馈能抑制网侧电流振荡。     

电流源型PWM整流器交直流侧解耦控制策略研究

三相电流源型整流器CSR(current source rectifier)作为恒压源输出时,直流侧并联大电容,使系统建模复杂度及控制难度大大增加,针对这一问题,将d轴定向于交流侧电容电压,简化d-q坐标系下动态数学模型。为抑制谐振和直流侧电压谐波,首先设计了一种交流侧采用虚拟电阻的有源阻尼控制,直流侧采用状态反馈控制的策略。通过整定状态反馈系数回馈状态变量来控制输出变量,提高系统的动态响应特性及直流稳压性能;利用高通滤波器,降低直流侧低频信号对交流侧的影响;因直流侧LC低频滤波特性,抑制了交流侧高频信号的影响,从而实现交直流侧的独立解耦控制。其次,调节q轴开关分量来实现网侧单位功率因数运行。最后采用Matlab/Simulink仿真验证该控制策略的合理性和可行性。     

电容均压三相四开关整流器多矢量模型预测控制

三相四开关整流器因其交流侧某一相直接连接在直流侧两电容中性点之间，存在着电容电压不平衡问题。为了保证电容电压平衡，且进一步提高三相四开关整流器控制系统的稳态性能，提出了一种电容均压的多矢量模型预测控制（multi-vector model predictive control，MVMPC）策略。针对三相四开关整流器无零矢量问题，建立等效零矢量模型；为保证直流电压的稳定，采用参考功率补偿策略来平衡直流侧电容电压；多矢量模型预测控制方面，每个采样周期选取两个基本电压矢量和一个等效零矢量，这使得等效合成矢量方向幅值均可调，扩大了等效合成矢量的作用范围，提高了系统的控制精度。仿真结果表明，电容均压多矢量模型预测控制策略能使三相四开关整流器可靠稳定地运行，对功率、网侧电流、直流侧电容电压等有着良好的控制效果；与传统的模型预测控制策略（conventional model predictive control，CMPC）相比，所提控制策略具有更小的功率脉动以及更低的电流谐波含量，且开关频率恒定，谐波电流分布规律。     

基于感容辅助网络的低谐波输入三相整流器

为了改善直流侧带电容滤波的三相二极管整流器的输入电流畸变,从拓扑形成规律出发,总结了在传统整流器输入侧增加感容辅助网络的无源校正方法,并依据不同的辅助网络结构,推出了八种低谐波输入三相整流器拓扑。优选了三种整流器拓扑,从电路工作模式、参数设计和变换器特性等方面进行了研究和对比。实验结果证实了该无源校正方法的有效性并揭示了该族整流器拓扑的一般规律,同时也证明了文中分析和设计方法的有效性,有利于推动该族整流器拓扑在实际中的应用。     

A multilevel-voltage source rectifier with a three-phase diodebridge circuit as a main power circuit

A novel system obtaining very low distorted waveforms of input AC currents of three-phase rectifier circuits are proposed. The proposed rectifier system consists of a three-phase diode bridge circuit as a main power circuit, AC reactors, and an additional circuit which serves as an active filter with low switching frequencies and a forced-commutation circuit for the diodes. This paper describes the operation principle, analysis of the waveforms of input voltage and current, multiple phase-shifted systems, and the experimental results. The proposed system gives excellent input current waveforms and has many advantages over conventional systems     

Three-phase active harmonic rectifier (AHR) to improve utility input current THD in telecommunication power distribution system

Modern telecommunication power supply systems have several parallel-connected switch-mode rectifiers to provide -48 V DC. A typical switch-mode rectifier configuration includes a three-phase diode rectifier followed by a DC-DC converter. Such a system draws significant harmonic currents for the utility, resulting in poor input power factor and high total harmonic distortion. In this paper, a three-phase active harmonic rectifier (AHR) scheme is proposed. In the AHR scheme, a diode rectifier module is replaced by a six-insulated-gate-bipolar-transistor pulsewidth-modulation rectifier to supply load harmonics as well as its own active power. Each DC-DC converter module is connected to a shared 48-V DC link. The AHR module together with parallel-connected switch-mode rectifiers is controlled to achieve clean input power characteristics. The VA ratings of the AHR scheme is compared with an active power filter approach. The control design is based on the synchronous reference frame approach. Analysis, simulation, and experimental results show that the AHR offers several advantages such as lower VA rating, better current control response, efficient use of the AHR DC link, small size, and stable DC-link voltage control.     

Combined rectifying system including double-series capacitor-smoothed diode rectifier and series active filter

This paper proposes a new rectifying system consisting of a series active filter and a double-series three-phase 12-pulse diode rectifier. The supply current in the proposed system has a sinusoidal wave shape because the series active filter suppresses the current harmonics produced by the diode rectifier. Since almost no 5th and 7th harmonics are produced by the double-series 12-pulse diode rectifier, the required peak rating of the series active filter is only 7% of the diode rectifier. In this paper, the control scheme and operating characteristics of the series active filter are theoretically and experimentally discussed. A novel conception that connection of a parallel capacitor to each diode of the rectifier makes a great contribution to reducing the required rating of the series active filter is also presented and verified by some experimental results. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(1): 85–94, 1997     

三相整流桥直流侧并联型有源电力滤波器

针对不可控三相二极管整流桥,提出了一种三相直流侧并联型有源电力滤波器拓扑结构及其控制策略,该滤波器由工作在工频的3个低频开关和两个串联的双向Boost电路构成。控制策略采用无需进行谐波电流检测和计算的单周控制方法,可抑制整流桥前端注入电网的谐波电流,使整个整流桥装置从电网吸收的电流接近正弦波,功率因数近似为1。与传统的交流侧有源电力滤波器相比,可以减少高频有源开关的数量,降低成本;与功率因数校正器相比,仅处理负载电流中的谐波分量,可减小谐波治理装置的额定容量。仿真和实验结果证明了所提方法的正确性。     

倍流整流三电平零电压软开关三相高功率因数整流器

提出一种新型的具有倍流整流的三电平零电压软开关三相高功率因数AC/DC变换器电路,该电路入端电感电流工作在DCM方式,以便实现高功率因数,输出滤波电感工作在CCM方式.与普通零电压三电平变换器比较,该电路在整个负载范围内更易实现功率管的零电压开关,无占空比丢失和二次侧电压尖峰.本文分析了电路工作原理,给出了高功率因数与电路参数的关系曲线,推导了电压增益公式和入端电感与输出滤波电感的设计公式,最后给出了实验结果.     

An approach to harmonic current-free AC/DC power conversion forlarge industrial loads: the integration of a series active filter with adouble-series diode rectifier

This paper proposes a new harmonic current-free AC/DC power conversion system characterized by the integration of a small-rated series active filter, with a large-rated double-series diode rectifier. The DC terminals of the active filter are directly connected in parallel with those of the diode rectifier, thereby forming a common DC bus. The active filter enables the diode rectifier to draw three-phase sinusoidal currents from the utility. In addition, it can provide the supplementary value-added function of regulating the common DC-bus voltage to a limited extent of ±5%, slightly increasing the RMS voltage rating, but not increasing the peak voltage rating. Experimental results obtained from a 5 kW laboratory system verify the practical viability and cost effectiveness of the proposed system     

VIENNA整流器的设计与优化

三相AC/DC整流器作为许多电力电子设备中不可或缺的电气环节得到了广泛的应用。相比于传统的二极管整流器及相控整流器,VIENNA整流器具有网侧谐波含量低、功率因数高的优点。同时,VIENNA整流器比普通桥式PWM整流器具有更少的功率开关数量,进一步提高了系统功率密度。在简要介绍VIENNA整流器原理的基础上,结合3 k W系统进行了相应的工程设计,主要包括储能元件设计、滤波环节设计和控制环路设计。此外,针对电网电压畸变带来的输入电流谐波问题,采用了一种结合VIENNA整流器控制环路的指定次谐波优化方法,并针对其中LCL滤波器带来的谐振问题,从工程设计的角度进行了相应的优化。3 k W工程样机的实验结果进一步验证了设计方法以及所采用的优化方法的有效性。     

VSI-PWM rectifier/inverter system with a reduced switch count

A current-controlled VSI-PWM rectifier and inverter with capacitor DC link is regarded as one of the most important structures for three-phase to three-phase power conversion. This type of power converter normally requires twelve switches for the rectifier and an inverter composed of self turnoff switch such as a bipolar transistor or an IGBT with an anti-parallel diode. In this paper, a new three-phase to three-phase AC/AC power converter for AC motor drives is proposed. The proposed power converter employs only eight switches and has the capability of delivering sinusoidal input currents with unity power factor and bidirectional power flow. This paper describes the feasibility and the operational limitations of the proposed structure. A mathematical model of the system is derived using the generalized modulation theory and experimental results for steady-state and dynamic behavior are presented to verify the developed model     

A new three-phase harmonic-free rectification scheme based on zero-sequence current injection

This paper proposes a new three-phase harmonic-free rectification scheme based on a zero-sequence injection technique. The proposed scheme incorporates two half-bridge inverters and two single-phase transformers to actively and individually shape the positive and negative dc rail currents of the rectifier. The shaped zero-sequence harmonic currents are then circulated through the ac side of the rectifier via a zigzag transformer, resulting in pure sinusoidal input currents in the three-phase diode rectifier. A design example along with component ratings calculation are detailed. Experimental results on a 1.5-kVA prototype are provided to validate the proposed technique.