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A New DC Side Capacitance Voltages Balancing Method for Three-level Inverters Based on Hybrid Space Vector Modulation 被引量:6
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作者 Fan Bishuang Tan Guanzheng +1 位作者 Fan Shaosheng Deng zelin 《中国电机工程学报》 EI CSCD 北大核心 2012年第27期I0017-I0017,共1页
Three-level neutral point clamped(NPC)inverters have been widely applied in the high voltage and high power drive fields.The capacitance voltage balancing algorithm is a hot topic that many specialists and scholars ha... Three-level neutral point clamped(NPC)inverters have been widely applied in the high voltage and high power drive fields.The capacitance voltage balancing algorithm is a hot topic that many specialists and scholars have been working on.V arious capacitance voltage balancing strategies have been studied,in which the redundant short vectors are not fully utilized.In order to increase the capacitance voltage control effect of the short vectors,a new algorithm is proposed. 展开更多
关键词 Three-level Inverter Virtual vector Hybrid space vector modulation Capacitance Voltage Balancing Time distribution factor
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Research of the Unity Theory Between Three-level Space Vector and Carrier-based PWM Modulation Strategy 被引量:28
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作者 CHEN Juan HE Yingjie WANG Xinyu LIU Jinjun 《中国电机工程学报》 EI CSCD 北大核心 2013年第9期I0010-I0010,共1页
两电平空间矢量脉宽调制(space vector pulse widthmodulation,SVPWM)与正弦脉宽调制(sinusoidal pulse widthmodulation,SPWM)存有一定的本质关系,对于三电平,在常见的8段式SVPWM序列中可以证明,SVPWM与SPWM本质上也存在某种统一... 两电平空间矢量脉宽调制(space vector pulse widthmodulation,SVPWM)与正弦脉宽调制(sinusoidal pulse widthmodulation,SPWM)存有一定的本质关系,对于三电平,在常见的8段式SVPWM序列中可以证明,SVPWM与SPWM本质上也存在某种统一。实际的SVPWM调制中,由于要考虑中点电压平衡、减少谐波等其它性能问题,一般会利用开关冗余状态得到8段以上的开关调制序列。目前的文献中还未曾有对这些情况进行统一性地验证,因此三电平SVPWM与SPWM的统一理论存在一定的不足。研究发现,可通过严格地理论推导将传统意义上的调制波分解为2个子调制波,再进行SPWM调制,可以得到与SVPWM完全吻合的序列。该文在此方法基础上深入研究了8段以上(10、12、14段)的SVPWM调制序列与SPWM的统一。经过严格地理论推导,成功实现了含任意段数的SVPWM序列与SPWM的统一。仿真结果证明了该理论的正确性。 展开更多
关键词 三电平逆变器 SVPWM 调制策略 统一理论 载波 矢量和 空间 研究人员
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Indirect Vector Control of Linear Induction Motors Using Space Vector Pulse Width Modulation 被引量:1
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作者 Arjmand Khaliq Syed Abdul Rahman Kashif +5 位作者 Fahad Ahmad Muhammad Anwar Qaisar Shaheen Rizwan Akhtar Muhammad Arif Shah Abdelzahir Abdelmaboud 《Computers, Materials & Continua》 SCIE EI 2023年第3期6263-6287,共25页
Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.T... Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.This research aims to present a novel framework for speed and thrust force control of LIM using space vector pulse width modulation(SVPWM)inverters.The framework under consideration is developed in four stages.To begin,MATLAB Simulink was used to develop a detailed mathematical and electromechanical dynamicmodel.The research presents a modified SVPWM inverter control scheme.By tuning the proportional-integral(PI)controller with a transfer function,optimized values for the PI controller are derived.All the subsystems mentioned above are integrated to create a robust simulation of the LIM’s precise speed and thrust force control scheme.The reference speed values were chosen to evaluate the performance of the respective system,and the developed system’s response was verified using various data sets.For the low-speed range,a reference value of 10m/s is used,while a reference value of 100 m/s is used for the high-speed range.The speed output response indicates that themotor reached reference speed in amatter of seconds,as the delay time is between 8 and 10 s.The maximum amplitude of thrust achieved is less than 400N,demonstrating the controller’s capability to control a high-speed LIM with minimal thrust ripple.Due to the controlled speed range,the developed system is highly recommended for low-speed and high-speed and heavy-duty traction applications. 展开更多
关键词 space vector pulse width modulation linear induction motor proportional-integral controller indirect vector control electromechanical dynamic modeling
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Realization of Space Vector Pulse Width Modulation Method Based on DSP
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作者 HAN Rukun ZHAO Yulin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期56-59,共4页
In order to compensate for the deficiency of Sine Pulse Width Modulation(SPWM), on the base of analyzing the principle of space w tot pulse width modulation and being compared with SPWM, the method of solving workin... In order to compensate for the deficiency of Sine Pulse Width Modulation(SPWM), on the base of analyzing the principle of space w tot pulse width modulation and being compared with SPWM, the method of solving working time of adjacent vector and the method of generate space voltage vector were introduced. The experiment to the inverter which consists of IGBT proves that SVPWM centrol algorithm can reduce harmonic effectively, it is beneficial to enhancing the utilization rate of voltage source inverter direct current power supply. 展开更多
关键词 space vector pulse width modulation DSP space vector
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Research on Parallel Interleaved Inverters with Discontinuous Space-Vector Modulation
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作者 Feng Yang Xu Zhao +1 位作者 Cong Wang ZhiFei Sun 《Energy and Power Engineering》 2013年第4期219-225,共7页
Parallel converter can significantly increase the capacity of the converter and improve the power quality of AC side, but the circulation which can lead to high switching loss and even damage the devices will easily e... Parallel converter can significantly increase the capacity of the converter and improve the power quality of AC side, but the circulation which can lead to high switching loss and even damage the devices will easily exist in the direct parallel converters. In this paper, the average model of parallel interleaved inverters system to analyze the circulation current is shown, and the cross current is relevant to DC-bus voltage and the overlap time of zero vectors in the switching period. Based on this observation, a discontinuous space vector modulation without using zero vectors (000) is eliminate and suppress the zero-sequence current to entire system. Finally, the effectiveness of modulation strategy is verified by the simulations in this paper. 展开更多
关键词 INTERLEAVED INVERTERS CIRCULATING Current DISCONTINUOUS space-vector modulation Zero- sequence
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ANFIS Based Space Vector Modulation-DTC for Switched Reluctance Motor Drive
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作者 T. Srihari R. Jeyabaharath P. Veena 《Circuits and Systems》 2016年第10期2940-2947,共9页
Direct torque control (DTC) of Switched reluctance motor is known straightforward control structure with similar execution to that of field situated control strategies. In any case, the part of ideal determination of ... Direct torque control (DTC) of Switched reluctance motor is known straightforward control structure with similar execution to that of field situated control strategies. In any case, the part of ideal determination of the voltage space vector is one of the weakest focuses in a routine DTC drive because of adjustable switching frequency and high torque ripple. In this paper, ideal choice of voltage space vectors is accomplished utilizing ANFIS (Adaptive Neuro Fuzzy Inference System) with space vector Modulation. SVM-DTC gives consistent switching frequency and the proposed ANFIS controller’s structure manages the torque and stator flux error signals through the fuzzy deduction to get a yield that takes the type of space voltage vector. Simulation results accept the proposed evolutionary system with quick torque and flux reaction with minimized torque ripple and flux ripple. 展开更多
关键词 ANFIS Direct Torque Control Flux Control space vector modulation Switched Reluctance Motor
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Classification of power quality combined disturbances based on phase space reconstruction and support vector machines 被引量:3
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作者 Zhi-yong LI Wei-lin WU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第2期173-181,共9页
Power Quality (PQ) combined disturbances become common along with ubiquity of voltage flickers and harmonics. This paper presents a novel approach to classify the different patterns of PQ combined disturbances. The cl... Power Quality (PQ) combined disturbances become common along with ubiquity of voltage flickers and harmonics. This paper presents a novel approach to classify the different patterns of PQ combined disturbances. The classification system consists of two parts, namely the feature extraction and the automatic recognition. In the feature extraction stage, Phase Space Reconstruction (PSR), a time series analysis tool, is utilized to construct disturbance signal trajectories. For these trajectories, several indices are proposed to form the feature vectors. Support Vector Machines (SVMs) are then implemented to recognize the different patterns and to evaluate the efficiencies. The types of disturbances discussed include a combination of short-term dis-turbances (voltage sags, swells) and long-term disturbances (flickers, harmonics), as well as their homologous single ones. The feasibilities of the proposed approach are verified by simulation with thousands of PQ events. Comparison studies based on Wavelet Transform (WT) and Artificial Neural Network (ANN) are also reported to show its advantages. 展开更多
关键词 Power Quality (PQ) Combined disturbance CLASSIFICATION Phase space Reconstruction (PSR) Support vector Machines svms)
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Harmonic Domain Modelling of Space Vector Based STATCOM
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作者 Devendra Manikrao Holey Vinod Kumar Chandrakar 《Energy and Power Engineering》 2016年第4期195-203,共9页
This paper presents frequency domain method for harmonic analysis of space vector based STATCOM. Space Vector Pulse Width Modulation (SVPWM) method is an advanced PWM method. It is a best method among all the PWM tech... This paper presents frequency domain method for harmonic analysis of space vector based STATCOM. Space Vector Pulse Width Modulation (SVPWM) method is an advanced PWM method. It is a best method among all the PWM techniques. It provides a freedom in a switching cycle for placement space vector. In this paper, the SVPWM is used for switching of STATCOM. The harmonic (or frequency) domain is a steady-state form of harmonic analysis method, which represents converters to their harmonic spectra. This paper presents harmonic analysis by means of harmonic domain for space vector based Static shunt converter (STATCOM). Performance of the STATCOM is evaluated in harmonic domain simulation studies in MATLAB environment. 展开更多
关键词 Harmonic Domain Voltage Source Converter (VSC) space vector modulation (svm) Static Shunt Compensator (STATCOM)
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Dynamic Harmonic Domain Modelling of Space Vector Based SSSC
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作者 Devendra M. Holey Vinod Kumar Chandrakar 《Energy and Power Engineering》 2016年第3期152-160,共9页
This paper presents analytical frequency domain method for harmonic modeling and evaluation of Space Vector Pulse Width Modulation (SVPWM) based static synchronous series converter (SSSC). SVPWM is the best among all ... This paper presents analytical frequency domain method for harmonic modeling and evaluation of Space Vector Pulse Width Modulation (SVPWM) based static synchronous series converter (SSSC). SVPWM is the best among all the PWM techniques. It gives a degree of freedom of space vector placement in a switching cycle. Dynamic modeling technique is used for space vector modulation (SVM) based voltage source converter that is adapted as a static synchronous series converter (SSSC) for harmonic analysis using dynamic harmonic domain. Performance of the SSSC is evaluated in dynamic harmonic domain simulation studies in MATLAB environment. The switching function spectra are necessary for harmonic transfer matrix which is calculated using Fourier series. This paper presents the analysis of harmonics for space vector based SSSC during steady state and dynamic condition. 展开更多
关键词 Dynamics Harmonic Domain Voltage Source Converter (VSC) space vector modulation (svm) Static Synchronus Series Compensator (SSSC)
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An Improved Hybrid Space Vector PWM Technique for IM Drives
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作者 P. Muthukumar P. Melba Mary S. Jeevananthan 《Circuits and Systems》 2016年第9期2120-2131,共13页
In this paper, an improved hybrid space vector pulse width modulation (HSVPWM) technique is proposed for IM (induction motor) drives. The basic principle involved in the proposed random pulse width modulation (RPWM) c... In this paper, an improved hybrid space vector pulse width modulation (HSVPWM) technique is proposed for IM (induction motor) drives. The basic principle involved in the proposed random pulse width modulation (RPWM) cuddled SVPWM is amalgamating the pre-calculated switching timings for various sections of hexagonal space vector boundary and the random selection of carrier between two triangular signals, in order to disband acoustic switching noise spectrum with improved fundamental component. The arbitrary selection between triangular carriers, which is decided by digital signal states (Low or High) of the linear feedback shift register (LFSR) based pseudo random binary sequence (PRBS) generator. The SVPWM offers a control degree of freedom in terms of positioning of vectors inside every sampling interval and hence it has six possible variants of the voltage vectors arrangements in each sector. The developed HSVPWM is thoroughly analyzed in using the MATLAB? based simulation for all SVPWM variants. From the simulation and experimental results viz. harmonic spectrum, harmonic spread factor (HSF), total harmonic distortion (THD) etc., and the superiority of the proposed scheme such as better utilization of DC bus and the randomization of the harmonic power are evidenced. For the practical implementation, Xilinx XC3S500E FPGA device has been used. 展开更多
关键词 Harmonic Spread Factor Hybrid space vector Pulse Width modulation Pseudo Random Binary Sequence Random Pulse Width modulation
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T型三电平逆变器驱动永磁同步电机容错控制
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作者 林海 宋春然 +1 位作者 程思怡 李演明 《吉林大学学报(工学版)》 北大核心 2026年第2期345-354,共10页
在T型三电平逆变器的永磁同步电机矢量控制系统中,开关管常出现开路或短路故障,此类故障会使原有调制策略失效,引起三相电流畸变,导致转速和转矩波动,严重影响系统稳定性。为解决这些问题,提出了一种容错T型三电平逆变器拓扑及相应的容... 在T型三电平逆变器的永磁同步电机矢量控制系统中,开关管常出现开路或短路故障,此类故障会使原有调制策略失效,引起三相电流畸变,导致转速和转矩波动,严重影响系统稳定性。为解决这些问题,提出了一种容错T型三电平逆变器拓扑及相应的容错五段式空间矢量脉冲宽度调制(SVPWM)策略。新拓扑能够将潜在的短路故障统一转化为开路故障,从而减少短路故障对系统的损害。根据故障相数对故障进行分类,当故障类型满足容错调制策略的可行性要求时,系统从原调制策略自动切换到容错五段式SVPWM策略,确保系统在故障状态下正常运行。仿真和实验结果验证了本文所提逆变器拓扑和容错调制策略在实际应用中的有效性和可靠性。 展开更多
关键词 T型三电平逆变器 空间矢量脉冲宽度调制 永磁同步电机 容错控制
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基于CMV抑制的五相永磁同步电动机扩频SVPWM策略
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作者 周华伟 胡越 +1 位作者 李龙彪 颜黎浩 《江苏大学学报(自然科学版)》 北大核心 2026年第2期198-206,共9页
针对基于相邻四矢量空间矢量脉宽调制策略的五相永磁同步电动机系统中共模电压高、传导电磁干扰严重等问题,提出一种基于抑制共模电压的扩频空间矢量脉宽调制(SVPWM)策略.首先,根据共模电压在电压源逆变器驱动的五相永磁同步电动机系统... 针对基于相邻四矢量空间矢量脉宽调制策略的五相永磁同步电动机系统中共模电压高、传导电磁干扰严重等问题,提出一种基于抑制共模电压的扩频空间矢量脉宽调制(SVPWM)策略.首先,根据共模电压在电压源逆变器驱动的五相永磁同步电动机系统中产生机理,选取方向相反的矢量代替基于相邻四矢量的空间矢量脉宽调制策略中的零矢量,以降低共模电压.其次,基于电流纹波以及高频谐波分布机理调整空间矢量脉宽调制策略的频率,以减小电流纹波和抑制传导电磁干扰.最后,搭建五相PMSM试验平台,将所提出RCMV-3SVPWM策略与传统NFV-SVPWM策略进行了对比,并对五相PMSM进行了动态跟踪性能试验.结果表明:所提出策略可将共模电压降低40%,电流纹波降至0.30 A,同时能有效抑制传导电磁干扰,而且具有优良的稳态和动态性能. 展开更多
关键词 永磁同步电动机 传导电磁干扰 电压源逆变器 电流纹波 共模电压 扩频调制 空间矢量脉宽调制
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基于反向传播神经网络的SVM技术在电压型变流器中的应用研究 被引量:13
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作者 李建林 李玉玲 +1 位作者 李淳 张仲超 《中国电机工程学报》 EI CSCD 北大核心 2005年第6期71-74,共4页
在分析三相电压型变流器空间矢量调制(SVM)技术基本原理的基础上,提出了一种基于反向传播神经网络结构的 SVM 技术(CPN-SVM)的实现方法。该方法采用CPN 竞争层来计算 SVM 中各个矢量的具体作用时间,避免了计算正弦函数这一非线性运算,... 在分析三相电压型变流器空间矢量调制(SVM)技术基本原理的基础上,提出了一种基于反向传播神经网络结构的 SVM 技术(CPN-SVM)的实现方法。该方法采用CPN 竞争层来计算 SVM 中各个矢量的具体作用时间,避免了计算正弦函数这一非线性运算,缩短了计算时间,采样周期的可进一步缩短。仿真和实验表明:CPN-SVM 除了具备 SVM 的固有优点外,还有下述几个显著优点:①大大降低了整个控制系统的软硬件成本,提高了对开关瞬态位置判断的准确性;②随着采用周期的缩短,最大开关频率相应增大,从而提高了整个系统的传输带宽③避免了由于计算误差给 SVM 波形中所带来的附带谐波。 展开更多
关键词 svm技术 反向传播神经网络 变流器 应用 空间矢量调制 神经网络结构 三相电压型 基本原理 作用时间 线性运算 正弦函数 计算时间 采样周期 控制系统 开关频率 计算误差 传输带宽 CPN 缩短 软硬件 准确性 仿真
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基于支持向量机(SVM)的回采工作面瓦斯涌出混沌预测方法研究 被引量:14
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作者 何利文 施式亮 +1 位作者 宋译 刘影 《中国安全科学学报》 CAS CSCD 北大核心 2009年第9期42-46,共5页
针对瓦斯涌出传统的线性预测方法存在的问题,根据瓦斯涌出时间序列固有的确定性和非线性,利用混沌动力系统的相空间延迟坐标重构理论,结合基于机器学习理论的支持向量机(SVM),建立基于SVM理论的瓦斯涌出混沌时间序列预测模型。经Ⅱ1024... 针对瓦斯涌出传统的线性预测方法存在的问题,根据瓦斯涌出时间序列固有的确定性和非线性,利用混沌动力系统的相空间延迟坐标重构理论,结合基于机器学习理论的支持向量机(SVM),建立基于SVM理论的瓦斯涌出混沌时间序列预测模型。经Ⅱ1024回采工作面瓦斯涌出时间序列仿真计算,仿真结果显示该预测模型具有比传统的回归方法更好的泛化能力,预测方法具有很高的预测精度。同时,该模型具有以往传统机器学习的瓦斯涌出预测模型建立简便、训练速度快等优点。由于充分考虑瓦斯涌出时间序列的混沌性,并利用SVM预测的优良特性,使得预测更科学。 展开更多
关键词 支持向量机(svm) 瓦斯涌出 混沌 相空间重构 时间序列
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改进的SVM决策树分类算法 被引量:10
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作者 史朝辉 王晓丹 +1 位作者 赵士敏 杨建勋 《空军工程大学学报(自然科学版)》 CSCD 北大核心 2006年第2期32-35,共4页
为解决多类分类问题,在分析SVM决策树分类器及存在问题的基础上,通过引入类间可分离性测度,并将其扩展到核空间,提出一种改进的SVM决策树分类器。实验表明了该分类算法对提高分类正确率的有效性。
关键词 支持向量机 svm决策树 可分离性测度 核空间
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中点电压偏移对SVM控制的三电平逆变器的影响及补偿措施 被引量:15
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作者 姜卫东 王群京 +2 位作者 李争 王智 陈权 《电工技术学报》 EI CSCD 北大核心 2006年第9期76-80,98,共6页
简要介绍了三电平逆变器的传统SVM控制算法。针对逆变器负载运行时,负载动态特性对于三电平逆变器的中点电压的影响,以及由中点电压偏移造成的空间矢量图的变化,引入中点电压前馈控制方法,进行新的矢量分区和作用时间计算,从而改进逆变... 简要介绍了三电平逆变器的传统SVM控制算法。针对逆变器负载运行时,负载动态特性对于三电平逆变器的中点电压的影响,以及由中点电压偏移造成的空间矢量图的变化,引入中点电压前馈控制方法,进行新的矢量分区和作用时间计算,从而改进逆变器带负载时的输出电流波形。在Matlab软件平台上进行仿真,结果表明改进的SVM得到的输出电流波形较传统的SVM控制方法下的输出电流波形有明显的改善。 展开更多
关键词 三电平逆变器 空间矢量调制 中点电压偏移
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无轴承异步电机SVM-DTC系统研究 被引量:5
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作者 刘贤兴 马桂芳 +2 位作者 任海涛 范崇盛 徐秋丽 《传感器与微系统》 CSCD 北大核心 2008年第12期39-42,共4页
针对无轴承异步电机这一多变量、非线性、强耦合的系统,采用空间电压矢量调制技术(SVM)与直接转矩控制(DTC)相结合的方法来控制无轴承异步电动机。阐述了无轴承异步电机的工作原理,给出无轴承异步电机的数学模型,将整个控制系统分为旋... 针对无轴承异步电机这一多变量、非线性、强耦合的系统,采用空间电压矢量调制技术(SVM)与直接转矩控制(DTC)相结合的方法来控制无轴承异步电动机。阐述了无轴承异步电机的工作原理,给出无轴承异步电机的数学模型,将整个控制系统分为旋转控制系统模块和悬浮控制系统模块,旋转模块引入SVM方法,并详细给出了基于定子磁链矢量偏差法的无轴承异步电动机SVM-DTC的分析与实现过程;悬浮模块采用电流追踪型PWM逆变器控制的方法。实验和仿真结果表明:转矩波动显著减少,运行更加平稳,系统具有良好的动态和静态性能。 展开更多
关键词 无轴承异步电动机 直接转矩控制 定子磁链 空间电压矢量调制
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基于简化SVM的模块化多电平变换器多子模块故障容错运行策略 被引量:18
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作者 白志红 李奕飞 马皓 《中国电机工程学报》 EI CSCD 北大核心 2021年第20期7104-7116,共13页
针对模块化多电平变换器(modularmultilevel converter,MMC)子模块数量多,故障率高的问题,文中研究单个或多个子模块发生故障后MMC的容错运行策略。文中首先将每6个子模块组合为一个子单元,提出一种简化的空间矢量调制(space vector mod... 针对模块化多电平变换器(modularmultilevel converter,MMC)子模块数量多,故障率高的问题,文中研究单个或多个子模块发生故障后MMC的容错运行策略。文中首先将每6个子模块组合为一个子单元,提出一种简化的空间矢量调制(space vector modulation,SVM)方法。在此基础上,对单个或多个子模块发生故障后的MMC的运行进行分析,根据不同故障子模块数量以及所在相的不同,将所有可能故障情况分为3类,针对每种故障情况分别提出相应的容错运行方法。仿真和实验表明,采用所提出的方法,即使MMC中有子模块发生故障,其输出线电压的幅值和谐波畸变率与正常运行情况相比基本不变,其运行可靠性得以提高。 展开更多
关键词 模块化多电平变换器 子模块故障 容错运行 空间矢量调制
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基于商空间粒度理论的大规模SVM分类算法 被引量:8
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作者 文贵华 向君 丁月华 《计算机应用研究》 CSCD 北大核心 2008年第8期2299-2301,共3页
利用商空间粒度理论对已有的SVM分类算法进行改进,给出了一种新的SVM分类算法——SVM-G。该算法将SVM分类问题划分成两个或多个子问题,从而降低了SVM分类复杂度。实验表明,改进的算法适用于处理大数据量的样本,能在保持分类精度的情况... 利用商空间粒度理论对已有的SVM分类算法进行改进,给出了一种新的SVM分类算法——SVM-G。该算法将SVM分类问题划分成两个或多个子问题,从而降低了SVM分类复杂度。实验表明,改进的算法适用于处理大数据量的样本,能在保持分类精度的情况下有效地提高支持向量机的学习和分类速度。 展开更多
关键词 粒度 商空间 支持向量机 分类 机器学习
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基于模糊DSVM控制策略的异步电机直接转矩控制 被引量:8
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作者 奚国华 张艳存 +2 位作者 胡卫华 喻寿益 桂卫华 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第1期166-171,共6页
针对传统的异步电机直接转矩控制系统低速转矩脉动大、磁链轨迹内陷、电流畸变严重以及开关频率不固定等缺点,基于离散空间电压矢量调制(DSVM)技术和模糊控制技术提出一种改善异步电动机直接转矩控制系统低速运行性能的控制策略。将一... 针对传统的异步电机直接转矩控制系统低速转矩脉动大、磁链轨迹内陷、电流畸变严重以及开关频率不固定等缺点,基于离散空间电压矢量调制(DSVM)技术和模糊控制技术提出一种改善异步电动机直接转矩控制系统低速运行性能的控制策略。将一个控制周期细分为m个时间片,每个时间片输出1个电压矢量,可以合成多个等效的空间电压矢量,供控制策略选择,优化了开关选择表。采用模糊控制器选择电压工作矢量,取代传统的滞环比较控制器。仿真结果表明,改进的DSVM控制策略及模糊控制算法的应用,有效改善了直接转矩控制的低速运行性能。在开关频率恒定的前提下,低速时磁链轨迹趋于圆形,电流谐波分量明显减少,平均转矩脉动降低为3.1%。 展开更多
关键词 直接转矩控制 模糊控制 离散空间矢量调制 低速性能
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