基于级联H桥变频器的极相调制感应电机驱动系统

高压电机配用高压变频器具有较大的节能性和高效性,已有广泛应用。级联H桥多电平变频器采用模块化设计理念,通过多个相同的低压变换单元级联起来实现高压及大功率的功能,且变频器输出电流谐波较小。极相调制感应电机可以将传统三相电机的控制方法和极相调制模式结合起来,使电机转矩和转速范围得到扩展。为此介绍一种级联H桥多电平变频器拖动极相调制感应电机变频起动和调速,该电机的定子绕组可配置为9相4极和3相12极。通过仿真验证了级联H桥多电平变频器能够满足极相调制感应电机的变频调速性能和极相调制矢量控制性能,可为新能源发电、船舶推进、工业传动等高压大功率领域提供技术保障。     

三电平H桥级联型逆变器

级联型多电平变频器输出电压谐波含量小,易于实现模块化,适用于高压大功率场合.本文主要针对三电平H桥级联型逆变器的拓扑结构和控制方式的相关问题进行分析与研究.级联个数不同,对控制方法也有不同的要求.提出了基于载波层叠调制和载波移相调制的混合载波调制方法,三电平桥臂内采用反相层叠载波调制,级联单元间及桥臂间均采用载波移相调...     

21电平H桥级联STATCOM调制技术仿真研究

H桥级联作为STATCOM主电路拓扑的主要结构,其调制策略是衡量STATCOM输出性能的一个重要指标。通过构建21电平H桥级联主电路结构并搭建载波移相(SPWM)和载波层叠式(SPWM)调制仿真模块。仿真结果表明载波移相调制能平衡各功率单元,但导致开关信号谐波增大;层叠波脉宽调制输出电压谐波低于载波调制,但各功率单元不平衡,易损坏开关器件。针对两种调制策略的优缺点提出了一种新的载波移相层叠波调制策略。仿真验证表明载波移相层叠波SPWM调制策略能够有效平衡功率单元和能降低开关信号的谐波含量。     

一种电动车用无刷直流电机混合回馈制动控制方法

在能量回馈制动原理的基础上,详细分析了无刷直流电机的半桥斩波回馈制动和全桥斩波回馈制动。针对半桥斩波非导通相续流的弊端和全桥斩波存在临界转速的缺点,提出采用全桥斩波和半桥斩波相结合的混合回馈制动控制新方法。该方法在临界转速以上采用全桥斩波回馈制动,以避免非导通相的续流,减小转矩脉动,实现平稳制动;在临界转速以下采用半桥斩波回馈制动,以减小能量损失,达到高效驱动的目的。仿真和实验结果表明,在制动中采用该方法既能高效回馈能量,又能实现平稳制动。     

混合H桥级联多电平逆变器改进PD调制策略

混合级联H桥多电平逆变器拓扑结构在采用常用的混合调制策略进行控制时存在电流倒灌和能量反馈的问题,在部分调制比区间内甚至会出现高压单元输出功率回馈到低压单元的现象,当低压单元直流侧电压由不控整流桥提供时会使得直流母线电容电压上升。为解决该问题,文中提出一种基于改进载波层叠调制的控制方法,其中,高压H桥单元采用方波与三角载波相结合的方法,低压H桥单元采用改进PD调制的方法,对混合频率下所得脉冲进行了重新的逻辑运算与组合,该方法既能解决电流倒灌和能量回馈的问题,还能使两单元之间的输出功率分配也得到了改善。最后进行了仿真和实验结果验证。     

基于能量回馈型的双PWM功率单元的研究

传统级联型逆变器由于功率单元输入端采用不控整流桥结构,不能实现能量的双向流动,因此限制了其在矿井提升机等一类需要四象限运行场合中的应用;采用一种三相PWM整流器的能量回馈型功率单元的拓扑结构,搭建了基于DSP+FPGA结构的四象限功率单元的低压实验平台,通过试验验证,将PWM整流器的控制算法应用于四象限功率单元中。     

合康变频：成熟技术履行经济节能承诺 访北京合康亿盛变频科技股份有限公司售前技术支持部经理曹永刚

北京合康亿盛变频科技股份有限公司是一家专业研发、生产高压、大功率变频器的高科技企业,2005年攻克了矢量控制及能量回馈两大技术难题,成功推出应用于高压异步电机四象限运行带能量回馈的HIVERT—YVF系列高压变频器;2006年又在超大功率高压变频器（成功出口俄罗斯）和同步高压变频器成功应用的基础之上,     

基于ARM的交流异步电机控制与馈电系统设计

基于ARM内核微控制器及智能功率模块,采用空间电压矢量脉宽调制技术及矢量控制方法,设计了一种三相异步电机变频调速控制系统。并针对通用变频器在快速启动、制动及频繁正反转调速场合再生制动的能量损耗问题,增加了一种再生制动能量逆变回馈电网装置。给出了系统的详细软硬件设计并进行实现。实验结果表明,系统控制精度高,实时性好,并实现了变频器的四象限运行,节能效果明显。     

一种混合模块型直流变压器冗余设计及控制策略

针对移相-谐振双有源桥(PS-SRDAB)混合型直流变压器(DCT),该文提出一种热备用冗余设计及其控制策略。为提高该类DCT内部谐振双有源桥(SRDAB)单元运行可靠性,将所备用的移相双有源桥(PSDAB)与其并联连接。在正常运行时,SRDAB与备用PSDAB单元同时工作,并通过控制高压侧电容电压实现两类模块内部传输能量配比。若SRDAB出现如过电流、过电压、过温等故障,对其进行闭锁后热备用PSDAB将承担模块全部功率。该文分析采用冗余设计时混合模块化直流变压器(HMDCT)的工作原理及运行特性,建立系统动态小信号模型,同时研究在采用传统电压闭环控制策略时的运行稳定性。利用所搭建的实验原理样机验证了所提出的冗余设计及控制策略的有效性。     

多级串联高压大功率矩阵变换器的研究

提出和采用载波移相调制原理,仿真分析一种降压变压器次级绕组功率平衡的多级串联高压变频器,即一个次级变压器承担对称的3个三相-单相矩阵变换器输出,输出相位相同的三相-单相矩阵变换器通过升压变压器次级串联,构成一相高压交流输出。整个电路由网侧工频降压变压器、单相矩阵变换器阵列、载侧高频升压变压器以及滤波电路构成。仿真结果表明,所提出的多级串联高压变频器具有可行性和低成本特征。     

Four-quadrant brushless ECM drive with integrated currentregulation

The authors present a method of regulating the phase currents in a brushless electronically commutated motor (ECM) during four-quadrant operation. Current information is obtained from current sensors integrated into MOS-gated switches, and the current regulation for motoring and regeneration is performed independently in each phase by gate-drive high-voltage integrated circuits (HVICs). Two commutation schemes are also presented for regeneration without the need for additional switches. The current regulation scheme provides protection against dangerous fault currents not sensed by conventional bus-shunt configurations. Control features incorporated in the smart-power components make it possible to achieve a high level of drive integration combined with enhanced protection for operation with supply voltages up to 500 VDC     

Theory and operation of a four-quadrant switched reluctance motor drive with a single controllable switch-the lowest cost four-quadrant brushless motor drive

Low-cost motor drives are being sought for high-volume energy-efficient home appliances. Key to the realization of such low-cost motor drives is the reduction of the power electronic converter to the barest in terms of its components, particularly the active devices, finding the motor with the least complexity for manufacturing and a controller that can extract the desired performance from the machine and converter combination. These and other factors such as self-starting, speed control over a wide range, and, most of all, the crowning aspect of four-quadrant operation with a bare minimum number of controllable switches remain as formidable challenges for low-cost motor drive realization. An innovative four-quadrant switched reluctance motor (SRM) drive with only one controllable switch is realized in this paper, for the first time, in the opinion of the authors. The motor drive is realized using a two-phase machine and a single controllable switch converter. The theory and operation of the proposed four-quadrant SRM drive with the proposed control algorithm for its realization are described. The motor drive is modeled, simulated, and analyzed to verify its feasibility for self-starting, speed control, and for four-quadrant operation, and the simulation results are presented. Experimental results confirm the validity of the proposed control algorithm for four-quadrant control of the SRM drive. The focus of the paper is mainly directed toward the control algorithm for realizing the four-quadrant operation of the two-phase SRM drive with a single controllable switch converter.     

Neutral Point Potential Balancing Algorithm at Low Modulation Index for Three-Level Inverter Medium-Voltage Drives

Three-level inverters produce low harmonic distortion of the ac currents even when operated at moderate switching frequency. This makes them the preferred candidates for high-power medium-voltage applications. To improve the utilization of the semiconductor devices, synchronous optimal pulsewidth modulation is employed. This permits reducing the switching frequency to very low values. Carrier modulation is maintained in the lower range of the modulation index. Operation at very low switching frequency increases the steady-state ripple of the neutral point potential. An intrinsic natural balancing mechanism of the neutral point clamped inverter topology eliminates long-term neutral point potential offsets. Transient conditions, however, may create successive increments of the offset to high values, which requires fast compensation. The novel method of selecting the appropriate redundant inverter sub-bridge meets this requirement without incurring additional penalties. The effectiveness of the approach is documented by experiments obtained from a medium-voltage motor drive fed by a 1-MVA three-level inverter     

A new modular motor-modular inverter concept for medium-voltageadjustable-speed-drive systems

In this paper, a new modular motor-modular inverter concept for medium-voltage adjustable-speed drive (MV-ASD) systems is introduced. It is shown that standard MV motor winding connections can be reconnected into several three-phase groups, each powered by a separate three-phase pulsewidth modulation inverter, resulting in a high-performance MV-ASD system. The proposed approach is fault tolerant and can continue to operate at reduced power levels, under inverter and/or motor faults. An example 250 hp four-pole 60 Hz 2300 V/4160 V motor winding connection diagram along with the associated inverter configurations is analyzed. Results from analysis are presented on the aspects of faults and motor operation under partial winding excitation. Experimental results on a low-voltage (460 V) 10 hp ASD are demonstrated     

中压变频调速系统试验

对中压传动系统试验分两部分进行介绍.在每一部分中,着重对检测项目和检测方法进行解说,其中对中压变频调速系统试验依据、试验要求及试验方法进行了介绍.并对变流器作为部件的标准试验项目和PDS变频器特有的试验项目的试验方法进行详细的介绍,对于一般性试验只进行简单的描述.希望能对中压变频调速系统试验在今后的不断完善和提高有所帮助.     

级联型高压变频调速系统共模电压分析

了解高压变频系统共模电压及其特点，对整个变频系统的设计具有重要意义。文中较详细地分析了级联型多电平高压变频系统共模电压的产生机理，对两种电压胞脉宽调制(PWM)方法引起的共模电压进行了比较，提出了采用电压胞异相调制和3次谐波注入法减小变频系统共模电压的策略。仿真计算表明，该方法既能减小变频系统输出共模电压，又不致降低直流电压利用率。     

有源钳位双向电压型高频链逆变电源的控制策略

针对有源钳位双向电压型高频链逆变电路拓扑,研究了一种新型单极性SPWM调制策略,采用对称三角载波与两个相位相反的正弦调制波调制产生所需的控制逻辑信号,该调制策略不需要根据输出电压极性信号来切换控制逻辑就能够实现四象限工作和各象限之间的平滑过渡,克服了原有的单极性调制在输出电压过零点畸变大的缺点.文中还设计了具有负载电流前馈的电压电流双闭环数字控制方案,电流内环可提高系统的稳定性,负载电流前馈能够提高系统抗负载扰动的能力,改善系统的动静态性能.在理论分析和仿真研究的基础上,设计制作了3kVA实验样机,实验结果验证了理论分析的可行性和系统设计的有效性.     

行波型超声波电动机的PWM控制驱动电源

介绍了一种基于PWM控制的行波型超声波电动机的驱动电源,重点介绍了变压器的优化设计思路,并通过实验确定了变压器的最佳参数;通过对不同占空比下电机的各项性能进行了综合比较和分析,确定了PWM波的最佳占空比。实验证明了这种电源比较适合超声波电动机的驱动。     

Theory and design of a 30-hp matrix converter

The control strategy and hardware design for a 30 hp matrix power converter (nine-switch forced-commutated cycloconverter) that was developed for high-bandwidth four-quadrant motor drive applications is described. The new switching technique ensures very low distortion of the input currents with unity fundamental displacement factor. Experimental results are presented     

背靠背四象限变流器的控制系统设计

介绍了背靠背四象限变流器控制系统的设计方案.整个控制系统由上层功率控制策略和底层PWM控制构成.在建立了背靠背四象限变流器在两相同步旋转坐标系下动态模型的基础上,提出了基于反馈线性化的非线性解耦控制器,并为背靠背两侧变流器分别设计了定直流电压和定有功、无功功率控制器.底层控制方面,设计了基于FPGA的空间矢量调制脉冲发生器.FPGA接收来自DSP的PWM控制参数,用于脉冲信号发生.最后给出了整个控制系统的硬件结构,并在30kVA/380V背靠背物理样机上进行了试验验证.