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针对传统无轴承永磁同步电机内部两套绕组结构复杂、可靠性低等缺点,提出了一种新型双三相绕组结构的无轴承永磁同步电机。电机采用分布式绕组结构并分为两个空间对称的独立三相绕组单元,通过两个三相逆变器在两个绕组单元中同时通入两组不同序列的电流实现电机的无轴承运行。推导了悬浮力与转矩数学模型。在Ansoft中建立有限元模型,分析了电机在两组电流控制下的磁场分布状况,分别计算了悬浮力与转矩随电流变化的关系,以及偏心磁拉力与转子偏移量的关系,仿真模型计算结果与理论模型计算结果基本吻合。建立了一种控制电机对称相电流不平衡的控制策略,将电机等效为两个普通三相电机,两个电机控制部分中的空间矢量脉宽调制模块SVM所需的信号由转矩电流参考值和悬浮力电流参考值合成再调制得到。采用Matlab软件构建了仿真系统,仿真结果表明,本文提出的双三相无轴承永磁同步电机在该控制策略下能够实现转子的高速旋转与稳定悬浮。 相似文献
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针对永磁同步电机在传统模型预测控制下,存在单个控制周期计算复杂、稳态电流波动较大、开关频率不固定等问题,提出一种三相电压矢量下的永磁同步电机占空比预测电流控制策略。该策略运用三相电压矢量进行预测控制,仅经3次预测后,利用最优、次优电压矢量进行一次占空比计算,经转化后即可得出两电平逆变器单控制周期内三相开关时间,从而输出任意幅值、相角的期望电压矢量。仿真结果表明,该策略与经典双矢量和三矢量预测电流控制相比,其控制性能更优异且耗时更短。 相似文献
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针对相移30°Y型连接双三相永磁同步发电机(DTP-PMSG),分别采用双d-q变换和空间矢量结构方法建立了不完全解耦和完全解耦的DTP-PMSG数学模型。对双三相PMSG进行空间矢量解耦分析,并分析了各子空间与机电能量的关系。分别对双三相PMSG的两种数学模型的矢量控制数字实现进行了理论分析。针对离散型最大四矢量法在一个开关周期内存在单个IGBT全开的现象,提出了一种改进的离散型的最大四矢量方法。最后对两种矢量控制方式进行了实验验证,实验结果表明在达到相同的母线电压时,两种控制方案的控制效果相同,谐波成分不同,验证了两种矢量解耦方式在双三相永磁同步发电机中的有效性。 相似文献
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半对称与全对称是多套三相永磁同步电机常见的2种定子绕组结构。该文针对不同绕组结构的多套三相永磁同步电机不对称缺相故障,以输出转矩最大为优化目标,提出一种统一的缺相容错电流计算方法。该方法综合考虑电机相数的奇偶性及绕组结构的差异性,通过引入偶数次谐波矢量及广义零序矢量重构解耦矩阵,适用于任意多套三相永磁同步电机缺相容错电流计算。最后,通过一台9k W九相半对称永磁同步电机的缺相容错控制试验,验证计算结果的正确性。 相似文献
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为了实现对双三相永磁同步电机绕组开路故障的快速诊断与定位,利用双三相永磁同步电机所特有的谐波子平面,提出采用谐波子平面电流矢量并结合归一化处理方案的双三相永磁同步电机绕组开路故障诊断策略。首先,根据故障前后谐波子平面电流矢量幅值大小的变化进行绕组开路故障的检测,其次,依据绕组开路故障后不同的电流矢量相角,准确定位出发生开路故障的绕组。为消除负载发生突变时可能造成的误诊断现象,进一步设计了针对谐波子平面电流矢量的归一化处理方案,提升对双三相永磁同步电机绕组开路故障诊断的鲁棒性。仿真和实验结果表明,所提策略能够快速地诊断并定位出绕组的开路故障,在负载发生突变时也可以表现出良好的可靠性和鲁棒性。 相似文献
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传统空间矢量调制技术只控制α-β平面的电压参考矢量,忽视了x-y平面的电压参考矢量,因此x-y平面产生较大的电流谐波分量,导致电机定子铜耗增加,影响电机控制性能。以双三相永磁同步电机为研究对象,采用2种4矢量SVPWM调制策略,同时控制α-β平面和x-y平面的电压参考矢量。结合电机解耦数学模型和基于id=0的矢量控制技术,对双三相永磁同步电机调速系统进行仿真分析。结果表明,两种SVPWM控制算法能够提高直流母线电压的利用率,输出电压接近正弦,电磁转矩脉动小,电流谐波含量少,定子铜耗低,验证了该方法的可行性和有效性。 相似文献
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Bojoi R. Lazzari M. Profumo F. Tenconi A. 《Industry Applications, IEEE Transactions on》2003,39(3):752-760
A direct rotor-field-oriented control of a dual-three phase induction motor drive is described in this paper. The induction machine has two sets of stator three-phase windings spatially shifted by 30 electrical degrees. The stator windings are fed by a current-controlled pulsewidth-modulation (PWM) six-phase voltage-source inverter. Three key issues are discussed: (1) the machine dynamic model is based on the vector space decomposition theory; (2) the PWM strategy uses the double zero-sequence injection modulation technique which gives good results with low computational and hardware requirements; and (3) to eliminate the inherent asymmetries of the drive power section, a new current control scheme is proposed. Experimental results are presented for a 10-kW dual three-phase induction motor drive prototype. 相似文献
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The stator of a brushless doubly fed machine (BDFM) is furnished with two sets of three-phase windings. These windings always have different pole numbers and are generally supplied at different frequencies. Investigation of the field distribution in a BDPM indicates that no polar symmetry can be associated to it. In addition, the motion of the field is not a simple rotation, as in a induction motor. Therefore, it is not expected that the representation of saturation by means of traditional saturation factors will yield useful results. In this paper, the authors describe a time-stepping finite-element model for the BDFM which can readily represent the effect of saturation. In addition, it is shown that iron losses can be calculated as the time-stepping solution proceeds. The model is verified using measurements made on a test machine. The use of saturation factors in conjunction with an analytical model is also investigated 相似文献
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建立了双绕组高压发电机的详细电路分析数学模型。模型可以用来分析双绕组高压发电机的稳态运行、外部相间故障或接地故障。采用理论分析方法计算了高压发电机的两套三相定子绕组的自感和互感,并且以11 MW、45 kV的双绕组高压发电机为模型,给出了稳态运行和故障时的仿真结果。利用该模型可以对高压发电机的保护方案进行有效的验证或者作相应的改进。 相似文献
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Multi-phase induction motors present excellent characteristics for faulty tolerant operation. Among them, six-phase induction motors, which are among the most used, exhibit two types of configuration: the double three-phase and the six-phase with single neutral. The double three-phase presents the advantage of reducing harmonics with its symmetric winding. This article presents a new modeling of the double three-phase induction machine for internal faults simulation. The developed model is composed by two sets of three-phase stator windings forming two stars. The model considers an arbitrary displacement (α) between stator stars, allowing the simulation of this type induction machines with different configurations, with 60° displacement used herein. The simulations of internal faults, such as stator windings or rotor faults, are both considered in the proposed model, allowing the machine study under abnormal conditions. The double three-phase induction machine model was fully implemented in real coordinates, making it possible to simulate stator and rotor faults without being necessary to change system equations coordinate. Several examples allow verifying the characteristics of the proposed model and its application for internal fault analysis. Experimental results are also presented to validate the obtained simulation results. 相似文献
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电力变压器在电网中运行,受到电网电压约束,分析其突发短路时的电磁过程,一般需要采用场路耦合的方法。T法具有求解变量少、计算代价小的优点,引入绕组的耦合电压项后,可用于电力变压器的计算。本文建立了三相变压器基于T-T0-W表述的场路耦合三维有限元模型,通过考虑变压器绕组的不同联接方式及多种负载情况,对变压器在不同短路情况进行了计算、分析。结果表明,在复杂短路过程中的短路电流可能超过突发三相短路时的最大电流。 相似文献
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A procedure for thermal analysis of a run-capacitor single-phase induction motor characterized by two different windings is presented. The procedure allows for the computation of the average winding temperature rise, and the temperature rises of the two different windings separately. The proposed thermal analysis is based on a lumped-parameter network commonly used for the three-phase induction motor. The paper illustrates how this network is adaptable for analysing the run-capacitor single-phase motor temperatures. In order to test the procedure, the predicted results are compared with those obtained from finite-element analysis and experimental data. Both comparisons show an appreciable agreement, confirming the validity of the analysis. 相似文献
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3/12相双绕组发电机数学模型研究 总被引:12,自引:5,他引:12
介绍了3/12相交直流同时供电(双绕组)发电机的结构特点。在某些近似假设条件下,将 12 相4Y互移15直流绕组等效为一个3相Y绕组,然后通过适当处理两套绕组之间的耦合,得出了与耦合有关的参数间的相互关系,从而简化了d-q-0 系统的数学模型、导出了简明的电压和磁链方程及相应的d和q轴等效电路,为分析该类电机的各项性能奠定了坚实的理论基础。该文所用方法同样适用于其它结构的双绕组发电机。 相似文献