四开关三相方波无刷直流电机的磁链跟踪控制

在分析传统六开关三相无刷直流电机运行原理的基础上,提出四开关三相方波无刷直流电机的磁链跟踪控制策略.系统外环为转速环,通过转速环输出和电流形状函数分别相乘实现三相电流的给定,借助坐标变换在两相静止坐标系下构建电流闭环,采用磁链跟踪型调制策略实现对四开关逆变器的控制,从而克服了滞环调制的开关频率不固定问题,实现了四开关三...     

New design for the high-performance drive system for DC brushless motor

The dc brushless motor, permanent magnet-type synchronous motor (PM motor), has been used widely in industrial robots, the machine tools for factory, and factory automations. Therefore, it is more desirable to improve the performance of the PM motor variable speed control system. Although only the torque component current is adjusted as the control method for the PM motor, so-called Vector Control, it is expected that the developed characteristics will be added to the PM motor. In this paper, new driving methods for the PM motor and a new design method for the variable speed control system are presented. The new motor driving methods which bring to the PM motor a new driving performance, e.g., a quick transient response or high-efficiency motor driving, can be implemented by controlling not only the torque component current, but also the magnetizing component current. A developed optimal control theory, i.e., the error system technique, is employed for designing the control system. The control law is endowed with a steady robustness against the variation of the system parameters and the ability of compensating the delay time due to the control processing. The effectiveness of the proposed method is confirmed by simulations and experiments.     

永磁无刷直流电机驱动系统的动态模型

具体分析逆变器—永磁无刷电机系统的工作过程以及此系统的一种动态模型 ,在此模型中 ,只要给出任一时刻转子的位置信号和电机的一些参数 ,就可以推测下一时刻的相电流、转矩等波形     

无刷直流电动机直接驱动系统动态特性分析

在推导了转子表面安装永磁体无刷直流电动机的数学模型的基础上,介绍了一种以集成数字信号处理器ＡＤＭＣ３３１为核心全数字矢量控制无刷直流电动机直接驱动系统。着重分析了电流参考信号超前角,系统参数和驱动方式对无刷直流电动机系统动态性能的影响。     

Remedial strategies for brushless DC drive failures

The possibility of developing failure diagnostics and remedial operating strategies, which together will make possible adaptive fault-tolerant operation, is investigated for a brushless DC motor drive with a fan load. Correlations between the predictions of a simulation program and test measurements are shown that provide confidence that the development of fault-tolerant drives can be undertaken with this tool. Methods by which a certain performance level can be reattained by a motor winding and an inverter transistor following some simple faults are examined     

AC brushless drive with low-resolution Hall-effect sensors for surface-mounted PM Machines

An ac brushless drive in which Hall-effect sensors are used as rotor position sensors is presented in this paper. Three different methods to obtain a high-resolution position estimation from the low-resolution sensors are described and compared through simulation and experimental testing. The proposed control algorithm's most innovative feature is its adaptability to the entire speed range, including startup, when using any of the three estimation algorithms. The control algorithm has been implemented and tested in order to drive a slotless axial-flux permanent-magnet (PM) machine for domestic appliance applications.     

永磁无刷直流电机的转矩计算及

电磁转矩的准确计算对于电机及其控制系统的设计具有重要意义。本文以ANSYS软件为工具,分析了永磁无刷直流电机不同定转子结构对于转矩的影响,论述了消除转矩脉动和提高电机出力的策略。     

一种检测无刷直流电机转子位置的新方法

针对传统的无刷直流电机无位置传感器检测转子位置信号需要多级模拟滤波器、复杂的相移电路以及与霍尔传感器输出的信号不一致的缺陷,本文提出了一种通过对三相端电压进行简单滤波、比较后直接获得转子位置信号的新方法.实验结果表明:新方法无需相移,检测的无刷直流电机转子位置信号和采用霍尔传感器输出的位置信号完全一致,可与霍尔传感器所采用的成本低廉的转子位置译码芯片相配套.     

Analysis and reduction of acoustic noise from a brushless DC drive

It has been found that stator excitation in brushless DC motor drives can excite mechanical resonances in the motor and, thus, produce acoustic noise in a similar way to switched reluctance drives. A technique has been developed to alter the commutation pattern of a brushless DC motor to avoid exciting and reinforcing these mechanical resonances producing a significant reduction in pure tone acoustic noise which is emitted during mechanical resonance. The origin of the vibration and acoustic noise is explained and the theory of discrete frequency noise reduction described in this paper. The method proposed for quieter control of the brushless DC motor could be achieved at a very low cost     

A novel microcontroller-based sensorless brushless DC (BLDC) motor drive for automotive fuel pumps

This paper presents a novel back-electromotive-force (EMF) detection method for sensorless brushless DC (BLDC) motor drive systems. By this method, a true back-EMF signal can be directly extracted for each phase without sensing the neutral point of the motor. The method proposed is not sensitive to switching noise and requires no filtering. Good motor performance is achieved over a wide speed range as well. This novel sensing scheme is implemented into a hardware macro cell inside a mixed-signal microcontroller. The proposed microcontroller-based sensorless BLDC drive system has been successfully applied to automotive fuel-pump applications, which require high reliability and intelligence at a low cost.     

集中绕组永磁无刷电机的转矩研究

集中绕组永磁无刷电机由于绕组结构与常规60°相带分布绕组不同,定子磁动势的谐波含量增加,定子齿、槽的影响也加大。本文采用电机磁能虚位移原理计算电机转矩,并编制了计算软件,不仅可以计算电机的平均电磁转矩,还可以得到由谐波磁场产生的谐波脉动转矩。通过实例计算,本文还比较了整数槽绕组和分数槽绕组产生谐波转矩的情况,采用分数槽绕组可以削弱谐波脉动转矩。     

无位置传感器无刷直流电机的控制策略

研究了无位置传感器无刷直流电机的控制方法,深入分析了反电势法的原理以及起动等技术要点,在完成实验系统后进行控制实验,并对实验数据和波形进行分析。结果表明,通过调节电机的外施电压可方便平稳地调节电机转速,并且整个控制系统工作正常。     

基于鲁棒调节器的无刷直流电机速度控制研究

本文提出了无刷直流电机的一种线性时变模型,分析了影响电机速度控制的负载扰动,在此基础上,设计了一种鲁棒速度控制器,对其设计方案进行了阐述,同时,针对速度不易检测的问题设计了全维转速观测器,最后,对速度控制系统进行了实验研究。     

无刷直流电动机转矩脉动抑制

通过对无刷直流电动机(brushless DC motor,BLDCM)典型PWM调制控制方式的分析,对新型的PWM开关模式进行了研究,证实了它能消除非换相区的非导通相绕组的二极管续流,进而大大降低非换相区转矩脉动.在该电机系统的换相区转矩脉动抑制方面,通过对换相区开与关不同相的上升与下降电流的分析,并基于功率变换器直流侧供电电压与电机反电动势的固定关系能消除换相区转矩脉动的机理,提出了在功率变换器主电路的直流侧增加ZETA变换器,当进入换相区时由可控的ZETA变换器向功率变换器供电,供电电压保持4倍于电机反电动势.通过实验证实了系统的非换相区和换相区转矩脉动抑制效果.     

无刷直流电动机的无位置传感器控制

无刷直流电动机的机械位置传感器影响着整个系统的可靠性、成本和体积,甚至在某些场合根本无法安装,因此无刷直流电动机的无机械传感器转子位置检测成为近年来学术界的研究热点。分析了目前国内外文献中所介绍的无位置传感器无刷直流电动控制技术中十种位置检测方法的原理、特点和适用范围,并针对起动方法,控制芯片及其在实际中的应用等相关技术的发展作了现状分析和展望,这些技术的发展可使无刷直流电动机无位置传感器控制系统获得更好的性能。     

无刷直流电机建模研究

针对无刷直流电机已有的建模方法过程复杂、计算量大、仿真收敛速度慢等缺点,按照系统电气原理结构进行物理连接的方法,建立了无刷直流电机的模型,在详细分析无刷直流电机5个模块构成的基础上,建立并给出了电机本体、转子位置检测、导通逻辑译码、脉宽调制和三相桥式逆变器的模型及设计原理.不同脉宽调制策略的仿真和实验结果表明:提出的方法建模过程简单直观、操作灵活、类似于实际电路的绘制过程,能快速仿真电机的实际运行特性.     

An approach to position sensorless drive for brushless DC motors

The authors describe a brushless DC motor without a position sensor. Variable speed is achieved by adjusting the average motor voltage, just like chopper control of DC motors. The position sensorless drive proposed is based on detection of the conducting interval of free-wheeling diodes connected in antiparallel with power transistors. This approach makes it possible to detect the rotor position over a wide speed range, especially at a lower speed. Experimental results obtained from a prototype brushless DC motor of 300 W rating are shown to confirm the validity of the sensorless drive from 45 to 2300 r/min. A starting procedure of the motor is also discussed because it is impossible to detect the rotor position at standstill     

Utilization of a series resonant DC link for a DC motor drive

A high-frequency series resonant DC link converter is utilized as a DC motor drive. This system generates a resonant current in a series link, and switching is done at zero current instants, reducing switching losses to a minimum value. A pulse density modulation (PDM) strategy, utilizing a current rectangular loop and an external motor speed feedback loop, controls the resonant converter. A sinusoidal input fundamental current and nearly unity input power factor can be observed in different load conditions. The overall characteristics of the system, including such variables as maximum power, input current, start up, and transient responses, are presented by digital simulation and were verified on an actual prototype system