Optimal design of a high-speed slotless permanent magnet synchronous generator with soft magnetic composite stator yoke and rectifier load

This paper presents a specific design methodology of a DC generation system using a high-speed slotless generator with surface-mounted magnets and soft magnetic composite (SMC) stator yoke connected to a rectifier. The method is based on an analytical design model of the machine, an electrical model of the machine-rectifier system and a non-linear optimization procedure. The coupling between both models is achieved by a specific correction mechanism during the iterative process that performs an efficient convergence of the optimization procedure. The machine design model is derived from an analytical computation of the two-dimensional magnetic field distribution created by the magnets, the armature currents and the stator eddy currents that circulate in the SMC material. It has been cross-validated by 2D finite element analysis. The design approach is applied to the specifications of a 1.5 MW, 18,000 rpm slotless permanent magnet generator with a rated DC output voltage of 1500 V.     

Lumped-parameter-based thermal analysis of a doubly radial forced-air-cooled direct-driven permanent magnet wind generator

A lumped-parameter-based thermal analysis of a direct-driven permanent magnet wind generator with double radial forced-air cooling is presented. In the proposed thermal model, the thermal conduction and convection as well as the heating of the cooling fluid are modeled in terms of thermal resistances. The electromagnetic losses of the generator are calculated by a two-dimensional, non-linear, time-stepping finite element method. The developed thermal calculation model can be applied both to static and transient problems. The performance of the proposed thermal model is compared with the results calculated by using computational fluid dynamics. The presented modeling strategy is implemented into an analytical calculation tool, which is used in the design process of a 3.35 MW high-torque low-speed direct-driven permanent magnet synchronous generator. Experimental results for a 3.35 MW permanent magnet generator are presented.     

基于DSP的离网型永磁同步发电机电压调节器

针对目前离网型永磁同步发电机输出电压不稳定及难以调节的问题,先将输出电压整流成直流电压,再将直流电压逆变为交流电压输出。逆变电路采用SPWM算法,并以DSP作为控制核心。经过整流、逆变后,发电机的输出电压稳定,并且能对输出电压方便地进行调节。     

Performance investigation of a permanent magnet generator

Computer simulation using the finite-element method (FEM) is an important tool for the design of highly efficient power devices. In this work combination of FEM-software for magnetic analysis and Simulink-software for non-linear parameter identification for dynamics of a permanent magnet (PM) generator is discussed. An FE model of the generator is developed and its electromagnetic torque analysis is carried out using FEM-software. Simulink has been used for analysis of rotor moment of inertia (MI) due to variation of winding resistance and winding inductance. It is shown that system MI has a significant effect on optimal winding resistance and inductance to achieve steady state operation in shortest period of time.     

虚拟$gamma-delta$旋转坐标系下考虑定子电阻摄动的永磁同步电机新型定子磁链观测器

针对永磁同步电机定子磁链观测受定子电阻变化影响的问题,提出一种$\gamma-\delta$ 旋转坐标系下的永磁同步电机新型定子磁链观测器.采用虚拟$\gamma-\delta$旋转坐标系代替传统α-beta静止坐标系,通过Lyapunov稳定性判据进行定子电阻动态辨识,在此基础上构建一种新型定子磁链观测器.实验结果表明,新型定子磁链观测器对定子电阻参数摄动和负载干扰具有较强的鲁棒性,实现了定子磁链的在线准确观测.     

Design of a PCB stator coreless axial flux permanent magnet synchronous motor based on a novel topology Halbach array

A novel topology Halbach permanent magnet array is proposed and applied to the design of a printed circuit board (PCB) axial flux permanent magnet (AFPM) motor. Compared with the traditional coreless AFPM motor, this novel topology for a Halbach permanent magnet array PCB stator AFPM motor has larger air-gap magnetic flux density and air-gap flux per pole. The magnetic flux leakage is effectively reduced, and the air-gap magnetic density is close to the sine wave. Results of the finite element analysis and prototype experiments verify the feasibility and effectiveness of the novel Halbach permanent magnet array PCB stator motor. A reference basis and practical value for the design of the PCB AFPM motor are provided.

     

永磁同步发电机风能转换系统滑模控制仿真

针对由于风速的随机波动性而使基于线性定常控制器的风能转换系统稳定性较差的问题,提出了一种基于滑模控制的永磁同步发电机风能转换系统的设计方案;分析了该系统中风力机模型、传动装置模型和永磁同步发电机模型的建立原理,介绍了滑模控制策略的具体实现。仿真结果表明,该系统具有较好的速度跟踪特性,实现了最大风能捕获。     

A rotor speed estimation algorithm in variable speed permanent magnet synchronous generator wind energy conversion system

A rotor speed estimation algorithm in a direct vector controlled permanent magnet synchronous generator wind energy conversion system is proposed. The proposed method is based on a simple equation obtained from the flux model of the machine and contains only stator flux and current. Constant gain recursive least squares estimator is used for implementing the speed estimation algorithm. Rotor position information used for coordinate transformation is computed using the estimated speed. Stator flux information required by the speed estimator is obtained using the stator voltage equation by implementing a programmable low pass filter. The estimated speed is used as the feedback signal for the speed control loop of the vector controlled machine side converter control system whose command speed is obtained from a wind speed sensorless maximum power point tracking controller, thus, we obtain a complete rotor speed and wind speed sensorless permanent magnet synchronous generator wind energy conversion system. Simulation is carried out to validate the performance of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd.     

Model predictive control of a permanent magnet synchronous motor with experimental validation

This paper develops new results on the use of model predictive control to regulate the speed of a permanent magnet synchronous motor where the design is based on a linearized state-space representation of the nonlinear model that describes the dynamics. The model predictive controller employs integral action, resulting in zero steady-state error and load torque disturbance rejection. Design in the presence of constraints is considered, where a quadratic programming procedure is used to solve the resulting on-line optimization problem during experimental verification by application to an industry-sized motor.     

Nonlinear predictive controller for a permanent magnet synchronous motor drive

A nonlinear predictive controller (NPC) for a permanent magnet synchronous motor (PMSM) is proposed in this paper. Its objective is high performance tracking of the rotor speed trajectory while maintaining the d-axis component of the armature current at zero. The load torque and the mismatched parameters are considered to be unknown perturbations. To ensure robustness against these perturbations, a disturbance observer is designed using a new gain function, and integrated into the control law. The combination of the nonlinear predictive controller and the disturbance observer works as a nonlinear controller. The overall closed-loop system is proved to be globally asymptotically stable depending on the design parameters. The validity of the proposed controller was tested by simulations. Satisfactory results were obtained with respect to the tracking of the speed trajectory and disturbance rejection.     

Adaptive control of permanent magnet synchronous machines with disturbance estimation

In this paper,an adaptive control scheme is introduced for permanent magnet synchronous machines (PMSMs)as an alternative to classical control techniques.The adaptive control strategy capitalizes on the machine’s inverse dynamics to achieve accurate tracking by using an observer to approximate disturbance in the form of friction and load torque.The controller’s output is then fed to a space vector pulse width modulation(SVPWM)algorithm to produce duty cycles for the inverter.The control scheme is validated through a set of simulations on an experimentally validated PMSM model.Results for different situations highlight its high speed tracking accuracy and high performance in compensating for friction and load disturbances of various magnitudes.     

永磁同步电机有限时间预设性能控制

为实现扰动作用下对永磁同步电机角位置伺服系统的高瞬态和稳态跟踪性能控制,本文提出一种具有预设性能约束的有限时间控制方法.首先,设计扰动观测器实现对负载力矩扰动的估计与补偿.其次,引入有限时间预设性能函数以保证角跟踪误差的动态性能,并通过可逆变换将受不等式约束的角位置跟踪误差转换为等效的无约束误差形式.然后,将有限时间指...     

An improved model predictive control of low voltage ride through in a permanent magnet synchronous generator in wind turbine systems

This research investigates a wind energy conversion system based on a permanent magnet synchronous generator (PMSG). In addition, a model predictive control (MPC) is proposed for the PMSG in normal and fault conditions. The most efficient mode of the control algorithm is found for maximum power point tracking in normal conditions and fast dynamic response in fault conditions following the selection of the optimum voltage vector. This method prevents a sudden increase in the DC‐link voltage by storing the active power in the generator rotor inertia. Moreover, during the low voltage, the grid code adoption of the reactive current is injected into the grid side. The performance of the proposed control scheme is evaluated for a wind power generator using MATLAB software. The simulation results demonstrate that the proposed method can safeguard the DC‐link during the fault.     

Nonlinear tracking control for sensorless permanent magnet synchronous motors with uncertainties

The recent advanced solution in Marino, Tomei, and Verrelli (2013) to the tracking control problem for sensorless IMs with parameter uncertainties is translated on the basis of letter swap connections between the models of (nonsalient-pole surface) permanent magnet synchronous motors (PMSMs) and induction ones (IMs). The (stability proof-based) nonlinear adaptive position/speed tracking control for sensorless PMSMs (with simultaneous estimation of uncertain constant load torque and stator resistance), which is accordingly obtained by exploring and decoding the design paths in Marino et al. (2013) and which surprisingly represents a simple generalization of the controller in Tomei and Verrelli (2011), constitutes an innovative solution to the related open problem. Illustrative experimental results are included.     

非均匀气隙永磁同步电机的自适应混沌同步

提出了一种非均匀气隙永磁同步电机(PMSM)混沌系统的同步控制方法. 首先通过多时标变换, 将转子磁场定向坐标系下的PMSM模型, 变换成一种简单的无量纲模型. 之后采用相图和分岔图的方法, 对PMSM的混沌动态行为进行了分析. 指出了倍周期分岔是非均匀气隙PMSM通向混沌的主要途径. 最后基于Lyapunov稳定性理论,设计自适应控制器, 实现了PMSM系统的混沌同步. 数字仿真结果验证了理论分析的正确性和控制方法的有效性.     

非均匀气隙永磁同步电机的有限时间混沌同步

针对非均匀气隙永磁同步电机(PMSM)混沌系统,提出一种改进的主动有限时间同步控制器.该控制器首先利用主动控制来实现动态误差系统非线性项和线性项的近似解耦,再通过有限时间稳定控制来实现驱动系统和相应系统的有限时间同步.通过仿真实验,验证了该控制器比传统的控制器具有更强的鲁棒性和快速响应能力.     

隔爆型变频一体化永磁同步电动机研制

国内刮板输送机转动惯量大,启动转矩大,导致其驱动电动机的启动比较困难,普通的异步电动机难以胜任。针对该问题,研制了1 200kW隔爆型变频一体化永磁同步电动机。该电动机采用优化的电磁方案,将电磁负荷控制在合理范围内,可满足弱磁调速要求;结构设计充分考虑变频供电特点、隔爆性能要求及体积和质量限制,符合相关防爆要求,且结构紧凑;冷却方案设计充分考虑散热能力和余量,确保电动机有合理的温升限值。有限元分析结果表明,该电动机主轴挠度和强度、铁芯隔磁桥强度均在合理范围内。样机试验结果表明,该电动机具有良好的恒转矩特性和调速性能。     

永磁同步电动机中混沌运动的部分解耦控制

永磁同步电动机在参数处于特定区域时存在混沌现象,混沌的存在将使电机的性能变差,因此要设法消除其混沌运动.电机中混沌的现有控制方法的控制目标只能为周期点或平衡点,不能满足实际需要.为了解决这个问题,设计了基于非线性反馈的永磁同步电动机中混沌现象的部分解耦控制.该方法以直轴和交轴电压为控制变量,通过电机状态的非线性反馈将直轴和交轴电流方程中的耦合项解耦,同时使得直轴和交轴电流可以跟踪设定值.这种控制方式的结果是使系统具有唯一稳定平衡点,而这个平衡点的位置可以根据实际要求设置为任意点.在任意时刻对处于混沌状态的永磁同步电动机进行部分解耦控制,受控系统将稳定于设定平衡点,从而实现混沌的控制.文中分析了控制参数与系统响应快速性之间的关系,为参数选择提供了指导.仿真结果表明了理论分析的正确性和该控制方法的有效性.     

永磁直线同步电动机推力波动抑制策略

永磁直线同步电动机自身存在的推力波动是阻碍其获得平稳的速度响应的一个重要因素,如何抑制推力波动的影响是系统控制器设计中必须考虑的一个问题.本文在分析了直线电动机推力波动特点的基础上,对其进行了测量.然后通过对推力波动测量结果进行频谱分析,找出其所包含的主要谐波,建立了推力波动的数学模型.最后基于所建立的模型,对推力波动进行了前馈补偿.当速度环采用滑模控制时,用实验验证了该方法的可行性.实验结果表明对推力波动进行建模和前馈补偿可以显著地改善速度环的响应性能.当系统以0.1m/s运行时,稳态速度波动范围下降到1.83%.     

对转永磁同步电机直接转矩控制方法

文章主要研究一种新型盘式结构,单定子、双转子对转永磁同步电机的直接转矩控制方法.首先,分析并建立了双转子对转电机的数学模型;其次,在一个逆变器不能同时直接控制两边转矩的情况下,根据两边转子位置差和电磁转矩与转矩角的关系,分时控制电机转矩波动较大一边转矩,来保证电机在不平衡负载时两边转子同步;最后,通过试验控制一台额定转速500 r/min,额定功率1.2 k W的盘式对转电机,验证了方法的可行性,并且电机运行稳定可靠.