凸极同步电动机的牵入同步

利用状态方程，研究了凸极同步电动机起动和牵入同步时的动态过程。针对1台1000kW的电动机，经过大量计算，得到了在75％额定负载和额定负载两种情况下，在16个不同的初始功角下投入额定励磁时，同步电动机牵入同步的动态过程；确定出牵入同步时较好和较差初始功角的范围，和在不同初始功角下能够牵入同步的最大负载值。所得结论对生产实践具有指导意义。     

考虑磁场饱和效应的凸极同步电动机建模

针对常规线性磁场模型难以准确描述凸极同步电动机的稳态和动态特性,磁场饱和效应严重影响高性能电动机驱动系统的控制精确度,对凸极同步电动机磁场饱和模型进行了研究.阐述了电动机d-q轴交叉饱和的机理,采用稳态饱和电感,动态饱和电感以及交叉饱和电感来表述磁场非线性的特征,建立了凸极同步电动机非线性磁场饱和模型,同时给出了其状态空间方程.采用矢量控制策略对凸极同步电动机的磁场饱和模型进行仿真分析,结果表明电动机的励磁电流能根据磁场饱和程度做出准确的响应建立电动机的磁场,d-q轴电流和负载功角的变化规律完全符合磁场饱和运行工况,验证了模型的有效性.     

Correction of static stability of synchronous motor with permanent magnets on rotor

The correction of static stability in a synchronous motor with the deviation of the rotor’s speed from the synchronous speed feedback loop is studied. The possibility of achieving static stability and transient high quality is indicated.     

Analysis of the static stability of a synchronous motor with permanent magnets by the classical method

Linearized differential perturbation equations have been derived. The static stability condition has been obtained in the form of simple inequalities. Stable and unstable parts have been determined on the electromagnetic torque dependence on angle of the stator field axis displacement from the rotor field axis in the stationary mode.     

基于载波注入的凸极永磁同步电动机无传感器控制

为了解决凸极永磁同步电机低速和零速时的转子位置估计问题，提出了一种载波注入的无传感器控制方法。在电机定子端注入高频正弦载波电压信号，利用空间凸极跟踪技术，从载波电流中取出位置估计的误差信号，再经过卡尔曼滤波器的处理，得到位置和速度估计信息。载波的恢复即高频信号的解调则通过一个带有外差作用的二阶低通滤波器来实现。仿真结果证实了这种方法的可行性，它适用于凸极永磁同步电机低速和零速时的转子位置和速度估计。     

Ensuring of static stability of a synchronous motor with permanent magnets by choosing optimal phase voltage

It is shown that, by choosing a sufficient gain of a stator current control circuit, it is possible to make steady-state modes with optimal efficiencies statically stable at any admissible load moments, while the modes optimal over cosφ will be statically stable only at moments smaller than the boundary one. The equations for the amplitude of the output signal of the current control circuit providing for the optimal steadystate mode are derived for the specified moment of load.     

Steady-state analysis of a self-controlled synchronous motor

This paper deals with a simple mathematical model for steady-state analysis of a self-controlled synchronous motor in terms of d,q variables. The flux linkage of the damper winding is considered constant under steady-state conditions. With the input voltage to the synchronous motor and the machine equations in d,q form, torque-current and speed-current relations are developed. The computed results are given and discussed in detail for a 3 kVA, three-phase, 400 V, four-pole, inverter fed synchronous motor and it is shown that this system has the same characteristics as a conventional DC motor.     

直线同步电机运行分析

为了深入研究直线电机的稳定运行特性,根据Maxwell原理,建立了分析直线同步电机稳态的电磁场数学模型.采用有限元方法进行离散,计算直线电机的磁场分布及电磁力,并开发了直线电机性能分析软件.软件计算得出直线电机悬浮力和推力随功角、电流变化等特性曲线的结果与ANSYS的计算结果一致,并具有模型简单、计算快速等优点,分析结果可为直线电机运行提供理论依据.     

同步电动机的动态和瞬态稳定极限

利用同步电动机的状态方程,研究了同步电动机在突加负载时的动态过程,经过多次迭代,分别得出了动态稳定极限和“首次摆动”瞬态稳定极限,并与由瞬态功角特性和等面积法则得到的瞬态稳定极限进行了比较,另外,还研究机组转动惯量对动态稳定极限和突加负载时动态过程的影响,最后得出了一些有用的结论。     

Low-order parametric force model for a salient-pole synchronous machine with eccentric rotor

In this paper, a low-order parametric force model to represent the electromagnetic force on an eccentric rotor of a salient-pole synchronous machine was developed and verified. The force model with parameters estimated from the results of impulse method showed excellent performance. The proposed model allowed quick and accurate calculation of the electromagnetic force at the desired whirling frequency values and provided an opportunity to effectively combine the electromagnetic and mechanical analyses of electrical machines. Besides, results presented in this paper also verified the suitability of computationally efficient impulse method for the analysis of a synchronous machine.     

正弦波永磁同步电机静态电流概述

数控机床中,已经使能的正弦波交流永磁同步电机零速状态下,其定子绕组存在持续静态电流,完成对伺服电机转子的锁定。针对正弦波永磁同步电机静态电流检测问题,结合运动控制系统理论和维修经验,提出一种交流永磁同步电机静态电流理论计算方法。     

带桥式交流器的凸极同步电机的稳态特性分析

本文给出了利用复数坐标变量系统解带桥式变流器的凸极同步电机稳态特性的计算方法,并对一台实际电机作了具体计算。计算波形和实验波形的一致性良好。文中还利用FFT对各电压及电流进行了诸波分析,并详细讨论了等效逆序电流的计算。最后,给出了计及谐波电流后的定子磁势。     

Blower drive system based on synchronous motor with solid salient-pole rotor: performance under starting and voltage sag conditions

This paper presents a study developed on a three-phase 11-MW synchronous motor with a solid salient-pole rotor of a blower drive system of a blast furnace at the Companhia Siderurgica Belgo-Mineira, Joao Monlevade, Brazil. A mechanical model including motor, gears, couplings, and blower is used in a simulation study to evaluate the torsional dynamics and stresses during motor startup and voltage sag conditions. In addition, the operation of the synchronous motor under voltage sag is analyzed with a comparative study between complete and approximated models of the motor. The utilization of a dynamic voltage restorer to protect the drive system under this abnormal situation is also evaluated.     

Computation of the no-load voltage waveform of laminated salient-pole synchronous generators

This paper presents a combined analytical and finite-element (FE) method for computation of the no-load voltage waveform of laminated salient-pole synchronous generators. The described method takes into account saturation effects as well as the damper bar currents due to the slot pulsation field. The method calculates first the damper bar currents and then includes them in the calculation of the no-load voltage. The combination of magnetostatic two-dimensional (2-D) FE simulations for calculating the magnetic coupling between the machine windings and of an analytical resolution results in a very precise prediction of the no-load voltage. At the same time, simulation time is drastically reduced compared with transient magnetic 2-D FE simulations. The method was verified on several examples, comparing the obtained results (damper bar currents and no-load voltage) with results obtained from transient magnetic FE simulations and, in one case, with the measured no-load voltage.     

Performance analysis of a reluctance synchronous motor under abnormal operating conditions

In recent years, the application of reluctance synchronous motors to ac drives has been gaining importance. In this paper, the performance of such motors under abnormal operating conditions (such as voltage unbalance) is analyzed and compared to their performance under normal conditions by means of motor current signature analysis. In order to permit an objective comparison of the simulation and experimental results, the influence of the supply time harmonics and constructional asymmetries of the machine is also considered. Detailed mathematical proofs are provided to support the results. Such analysis will be helpful for understanding and identifying stator inter-turn faults unambiguously. To the best knowledge of the authors, such an analysis has not been carried out previously.     

电压下降时同步电动机的动态稳定极限

利用同步电机的状态方程，研究了同步电动机在电压下降时的动态过程。经过多次迭代，分别得到了当电压下降为不同值时，同步电动机保持动态稳定的极限时间；以及不同的机组惯性常数和电机的励磁状态对动态稳定极限时间的影响；最后得出了一些有用的结论。     

永磁感应子式无刷直流电动机的转矩特性研究

针对永磁感应子式无刷直流电动机的定转子齿结构和绕组的排列对转矩特性的影响,从特定电机结构的磁导计算出发,推导出永磁感应子式无刷直流电动机的参数表达式,分析了电机的参数特征对转矩工作特性的影响。实验及分析表明,采用等效磁路和实际测量相结合的方法．可以预测永磁感应子式无刷直流电动机的电磁转矩和齿槽定位力矩特性,为电机的转矩控制提供理论依据。     

Real-time power angle determination of salient-pole synchronous machine based on air gap measurements

This paper presents a new method for the real-time power angle determination of the salient-pole synchronous machines. This method is based on the terminal voltage and air gap measurements, which are the common features of the hydroturbine generator monitoring system. The raw signal of the air gap sensor is used to detect the rotor displacement with reference to the fundamental component of the terminal voltage. First, the algorithm developed for the real-time power angle determination is tested using the synthetic data obtained by the standard machine model simulation. Thereafter, the experimental investigation is carried out on the 26 MVA utility generator. The validity of the method is verified by comparing with another method, which is based on a tooth gear mounted on the rotor shaft. The proposed real-time algorithm has an adequate accuracy and needs a very short processing time. For applications that do not require real-time processing, such as the estimation of the synchronous machine parameters, the accuracy is additionally increased by applying an off-line data-processing algorithm.