无刷同步电动机的变频运行方式的研究

近年来随着节能观念的转变,大量的无刷同步电动机将面临变频改造。本文简要介绍了无刷同步电动机的结构、原理和运行方式,对无刷同步电动机在变频运行中所遇到的投励、整步、励磁调节等问题进行了详细的分析,提出了无刷同步电动机的变频运行方式,使得在该方式下,变频器能够驱动无刷同步电动机可靠、经济地调速运行。     

新型混合励磁无刷爪极发电机的研发

传统的电励磁爪极发电机存在发电效率低、磁场调节困难的问题,对此我国的技术人员提出了一种新型的混合励磁无刷爪极发电机。本文将对新型混合励磁无刷爪极发电机的结构、磁场运行规律,以及新型混合励磁无刷爪极发电机对磁场的调节能力进行具体分析,希望能给相关人士提供一些参考。     

高压变频器在增安型无刷励磁同步电动机上的应用

无刷励磁同步电动机由于没有滑环、碳刷等可能产生火花的环节,在化工、煤矿等具有爆炸性环境的场所有着较为广泛的应用本文基于本公司成功的改造无刷励磁同步电动机的经验,对无刷同步电动机在变频运行中所遇到的各种问题进行了详细的分析.并提出了解决方法,使变频器能够驱动无刷同步电动机可靠、经济地调速运行。     

大型同步发电机转矩系数的计算与分析

从电机的基本方程出发,推导出了大型同步电机在功角作正弦小振荡时的电磁转矩的变化,根据整步转矩系数与阻尼转矩系数的定义,给出了大型同步电机整步转矩系数与阻尼转矩系数的表达式,计算出了大型同步电机整步转矩系数和阻尼转矩系数。     

无刷同步电动机旋转励磁器升级后应用实例

高安全性能的压缩机是氢气加压裂化所需的重要设备，需要使用无刷励磁同步电动机来驱动，并且其启动和运行性能有苛刻要求。2014年独石化乙烯厂制氢车间技术改造时，换用TAKW450-18增安型大型高压无刷同步电动机，其旋转励磁器采用WLK-03SC/N1替代了已经运行近10年的旧装置。本文介绍了该WLK-03SC/N1励磁器的结构、功能、工作原理及其优点。实践表明新装无刷同步电动机能够满足压缩机安全性的要求，保证了加压氢裂装置的稳定运行。     

火电厂发电机励磁系统现场试验方法和常见问题

<正>同步电机励磁系统在国标中的定义是"提高电机磁场电流的装置,包括所有调节与控制元件,还有磁场放电或灭磁装置以及保护装置"。其主要作用就是维持机端电压的恒定。当机端电压上升时,励磁调节的结果是使其下降;而发电机端电压下降时,励磁调节的作用是使其上升。从励磁系统的励磁方式来看,主要有常规励磁(三机系统)、自并励、两机它励、无刷高起始励磁系统等几种。本文讨论     

无刷直流风扇电机180°正弦波控制

目前的变频风扇一般采用无刷直流电机,因其无励磁绕组、无换向器、无电刷、无滑环,结构比一般传统的交、直流电动机简单,运行可靠,维护简单。与鼠笼型感应电动机相比,其结构     

大型同步电机中励磁控制技术的研究

大型同步电机因其运行稳定、输出功率大、能向电网发送无功功率、支持电网电压、提高功率因数等优点被广泛应用于大型电力排灌站、大型水利枢纽泵站以及冶金、机械、化工等大型企业的生产中。励磁控制系统是同步电机的重要组成部分,其特性好坏直接影响到同步电机的可靠性和稳定性。文章针对目前同步电机中励磁控制技术存在的弊端加以改进,提出切实可行、行之有效的改进技术措施,大大提高了电机工作的可靠性和稳定性。     

复阻抗法验证凸极同步电机双反应理论研究

本文从同步电机电感和电枢反应磁势出发，推导单相交流供电在转子静止且无励磁时纯直轴、纯交轴，以及一般电枢反应状态下的电压方程和复阻抗，确定验证双反应理论的复阻抗关系，从而通过实验测量验证双反应理论的有效性。该方法也可以作为同步电机电感参数测量方法，有助于深入理解双反应理论和同步电机运行规律。     

无刷双馈电机控制与应用前景

无刷双馈电机(BDFM)是一种新型交流电机,它兼有异步电机和同步电机的共同优点,去掉了转子侧电刷,提高了机械稳定性,降低了维修成本。本文详细综述了无刷双馈电机的发展历史、运行原理、数学模型、控制策略,简单介绍了无刷双馈电机的应用,并对其发展前景作了展望。     

基于MC9S12X128无刷直流电机控制系统设计

为满足对直流无刷电机控制要求精度高、调速性能好、系统实现成本低的需要,设计了一种无刷电机控制系统。该系统以MC9S12X128单片机为控制核心,采用IR2130芯片驱动MOSFET功率管,实现对直流无刷电机三相六拍PWM控制。系统硬件电路结构简单、调速方便、功耗低。实际运行测试表明,电机可以长期稳定运行。     

基于有限元分析的直流电机控制策略

无轴承无刷直流电机集成了直流和交流电机的优点,具有重要的实际应用价值,针对传统悬浮力控制方法存在工作复杂、逆变器通断频繁等缺陷,为了提高磁悬浮力的控制效果,提出了基于有限元分析的无轴承无刷直流电机悬浮力控制策略。首先对无轴承无刷直流电机的结构以及悬浮力产生的原理进行了分析,然后采用有限元分析法对电机转矩和悬浮力进行计算,从而实现无轴承无刷直流电机控制,最后采用Matlab/Simulink工具对其性能进行测试与验证。结果表明,本文策略可以提高转子悬浮的稳定性,能够保证无轴承无刷直流电机的正常运行。     

Indirect rotor position sensing in real time for brushlesspermanent magnet motor drives

This paper describes a modern solution to the real-time rotor position estimation of brushless permanent magnet (PM) motor drives. The position estimation scheme, based on flux linkage and line-current estimation, is implemented in real-time by using the abc reference frame, and it is tested dynamically. The position estimation model of the test motor, development of hardware and basic operation of the digital signal processor (DSP) are discussed. The overall position estimation strategy is accomplished with a fast DSP (TMS320C30). The method is a shaft position sensorless method that is applicable to a wide range of excitation types in brushless PM motors without any restriction on the motor model and the current excitation. Both rectangular and sinewave-excited brushless PM motor drives are examined, and the results are given to demonstrate the effectiveness of the method with dynamic loads in closed estimated position loop     

Analysis of brushless permanent magnet synchronous motors

A brief design review of permanent magnet synchronous motors has been presented. A procedure has been developed to predict the steady state and dynamic performances of a brushless permanent magnet synchronous motor. Finite element analysis has been combined with a lumped parameter circuit model in order to provide satisfactory engineering information. To this end, two coordinated steps are involved. One is to develop a unified lumped parameter circuit model for both steady state and dynamic analysis. The second step is to extract the individual lumped parameters from finite element solutions based on corresponding equivalent circuits, each with a pre-determined topology. The proposed techniques have been experimentally verified in a laboratory permanent magnet synchronous motor     

高压变频器在烧结主排风机起动装置中的应用

本文介绍了AB公司的POWERFLEX 7000高压变频器在某钢铁公司二期烧结工程2台容量为7800kW无刷励磁同步电动机拖动的主排风机进行变频软启动的情况,说明了这种电流型变频器的优点,并介绍了调试与维护的经验。     

Neural net-based robust controller design for brushless DC motordrives

A nonlinear neuro-controller is developed for controlling the speed of brushless dc motors operating in a high performance drives environment. The control inputs and the identification parameters of the system are adjusted simultaneously in real time using a system composed of three hidden-layer dynamic neural networks while the system is in operation. The control architecture adapts and generalizes its learning to a wide range of operating conditions and provides the necessary abstraction when measurements are contaminated with noise. The problem of persistently spanning excitation faced with the use of an online neuro-controller is addressed. In particular, the ability of the neuro-controller to “remember” previously trained reference tracks when confronted with an input excitation that is markedly different from what it was trained with is investigated. The intent is to capture the nonlinear dynamics of a brushless dc motor over any arbitrary time interval in its range of operation. The sensitivity of real time neuro-controllers to random changes in the load torque also is investigated and very promising results are observed     

无刷直流方波电机PWM控制器的设计

稀土水磁无刷直流方波电机是一种新型电动机，其性能优越，发展前景广阔。本文介绍了无刷直流方波电机的工作原理和其PWM控制器的设计。     

The state-space analysis of excitation regulation ofself-controlled synchronous motor with constant margin-anglecontrol

A state-space model of self-controlled synchronous motor was established with finite DC inductance and main flux saturation effects considered. Using the model, the excitation regulation of the self-controlled synchronous motor under the control of constant margin-angle and constant main flux level was investigated to enhance the overload capability and to ensure the operation stability