Robotized stator cable winding

Automated stator winding assembly has been available for small and medium sized conventional electric machines for a long time. Cable winding is an alternative technology developed for medium and large sized machines in particular. In this paper we present, evaluate and validate the first fully automated stator cable winding assembly equipment in detail. A full-scale prototype stator cable winding robot cell has been constructed, based on extensive previous work and experience, and used in the experiments. While the prototype robot cell is adapted for the third design generation of the Uppsala University Wave Energy Converter generator stator, the winding method can be adapted for other stator designs. The presented robot cell is highly flexible and well prepared for future integration in a smart production line. Potential cost savings are indicated compared to manual winding, which is a backbreaking task. However, further work is needed to improve the reliability of the robot cell, especially when it comes to preventing the kinking of the winding cable during the assembly.     

Utilizing cable winding and industrial robots to facilitate the manufacturing of electric machines

Cable wound electric machines are used mainly for high voltage and direct-drive applications. They can be found in areas such as wind power, hydropower, wave power and high-voltage motors. Compared to conventional winding techniques, cable winding includes fewer manufacturing steps and is therefore likely to be better suited for automated production. Automation of the cable winding production step is a crucial task in order to lower the manufacturing costs of these machines. This article presents a production method using industrial robots for automation of cable winding of electric machine stators. The concept presented is validated through computer simulations and full-scale winding experiments, including a constructed robot-held cable feeder tool prototype. A cable wound linear stator section of an Uppsala University Wave Energy Converter and its winding process is used as a reference in this article. From this example, it is shown that considerable production cycle time and manufacturing cost savings can be anticipated compared to manual winding. The suggested automation method is very flexible. It can be used for the production of cable wound stators with different shapes and sizes, for different cable dimensions and with different winding patterns.     

Simulation and optimization of automated masonry construction using cable robots

A cable-driven parallel robot for automated masonry construction is currently under development. Besides the mechatronic design and component engineering, a simulation framework has been realized to optimize the cable robot motions with respect to technical and economic requirements, which supports both the prediction of the potential and limitations of this approach as well as the reduction of the risk for further development activities.The framework generates suitable trajectories for every masonry unit to be placed, considering several requirements and optimization criteria. These include motion time, collision avoidance, stiffness, cable forces and energy requirements. The framework uses a hybrid particle swarm algorithm for global optimization.The paper presents the trajectory modeling and the definition of the cost functions derived from physical models of the cable robot. It includes the analysis of simulation results that illustrate the generated trajectories.     

Optimal regulation of a cable suspended robot equipped with cable interfering avoidance controller

Closed-loop regulation of a spatial cable suspended robot is performed in this paper subject to maximizing the Dynamic Load Carrying Capacity (DLCC) of the end-effector while the cable interference is avoided actively. Optimization is performed between two predefined boundaries and considering the cable interference constraint. This constraint is satisfied by designing a controller which prevents the cables’ collision. The overall formulation of the closed-loop optimal control based on Feedback linearization is derived in this paper for planning the optimal path with the highest load capacity. Then a complementary adaptive controller is designed and implemented to the main controller which is responsible for providing cable interfering avoidance. The efficiency of the designed controller for preventing the cables’ collision is shown by performing and analyzing some comparative simulations conducted on an under constrained cable robot with six cables and six DOFs. All results related to regulation, tracking and DLCC are compared between the simple optimal closed-loop system and the system which is equipped with the proposed cable interfering avoidance controller. It is proved that the planned path satisfies cable interference constraint while its DLCCs are optimized.     

Physically based real-time interactive assembly simulation of cable harness

In this paper, we designed and developed an interactive assembly simulation system of cable harness. First, we establish a real-time physical model of cable harness based on an extension of the mass–spring model. We use various kinds of springs to describe the different properties of the cable harness: linear springs for stretching, bending springs for bending, and torsion springs for geometrical torsion and material twisting. The constraints of connectors and clips on cable harness are both considered. We also associate the elastic coefficients of various springs with the material parameters of the cable. Moreover, we use spherical bounding volume hierarchy and triangular facets for collision detection of cable harness during the assembly simulation. By applying contact forces to both ends of the cable links that collide with the surrounding environment, we obtain the real-time contact response of cable harness. Finally, we apply the proposed model to a cable assembly task. The results show that the proposed model successfully expressed the deformation of the cable harness and the interactive manipulation is computationally efficient.     

Trajectory planning of a suspended cable driven parallel robot with reconfigurable end effector

In this paper, a new suspended cable driven parallel robot (CDPR) with reconfigurable end effector is presented. This robot has been conceived for pick and place operations in industrial environments. For such applications, the possibility to change the configuration of the cables at the end-effector level is a promising way to avoid collisions with obstacles in the approaching phases, while reducing at the same time the duration of motion in the remaining part of the trajectory. An optimized trajectory planning algorithm is proposed, which implements a pick and place operation in the operational space with dynamic on-line reconfiguration of the end effector. The results on a simplified scenario demonstrate the ability of the system to obtain reduced movement times together with obstacle avoidance.     

基于MATLAB／Simulink的双馈感应电机建模与仿真研究

双馈电机的结构类似于绕线式感应电机,其定子绕组也由具有固定频率的对称三相电源激励,所不同的是其转子绕组由可调节频率的三相电源激励,一般采用交-交变频器或交-直-交变频器提供低频电源。本文在推导双馈电机在静止参考坐标系中的数学模型的基础上,应用矢量控制技术建立了双馈电机电流闭环控制。通过仿真获取该电机的电流、速度和磁通曲...     

Design,analysis and control of a winding hybrid-driven cable parallel manipulator

This paper is related to the design, analysis and control of a winding hybrid-driven cable parallel manipulator (WHCPM). The WHCPM has the advantages of both cable parallel manipulator and hybrid-driven planar five-bar mechanism. Design of the WHCPM is explained, and the structure static analysis is carried out by using finite element method. Dynamics and payload capability of the WHCPM are studied. The WHCPM prototype is built for precision tracking experiments. To evaluate the manipulator design, the dynamic control compensation is performed on the basis of the conventional PID controller and the adaptive fuzzy sliding mode controller. The simulated and experimental results are reported and the tracking performance of the WHCPM is significantly improved by applying the proposed control technique in comparison with the performance when applying the conventional PID controller.     

基于智能传感视觉的电缆裸露风险模式识别指标分析

为了避免电缆裸露造成的工程作业故障等问题,提出基于智能传感视觉的电缆裸露风险模式识别指标分析。通过了解致使电缆裸露因素,分析电缆裸露风险识别指标和原理,对电缆破损数据进行预处理。采用SVD方法提取数据特征,引入智能传感视觉技术实现电缆破损数据重构,从而完成对电缆裸露风险模式识别指标的分析。实验结果表明,所提方法分析准确性高,有效降低电缆裸露风险,减少电力传输过程的损失。     

A new mathematical tool to investigate the influence of cable characteristics and IGBT fast switching on voltage transients and differential mode currents for PWM drives

The authors propose a new mathematical tool to investigate the influence of cable characteristics upon pulse voltage transients and their associated differential mode (DM) currents in PWM long cable drives. Even if reflected wave transient voltages have received considerable investigation for IGBT voltage source inverters, the modeling and simulation of these voltage transients still require precise modeling. Moreover, another consequence of the IGBT fast rise time, which is the resulting high frequency DM current, has not been previously examined in detail for these systems.This paper presents fully developed mathematical formulas for both pulse voltages and their resulting DM currents at any point along the inverter-to-motor cable. Using the developed formulas, an appropriate tool has been built, using SimPowerSystems (SPS) and Simulink of Matlab software, to predict the high frequency over-voltages and their associated DM currents all along the feeding cable. This tool has then been applied to an industrial 5 kV A PWM drive prototype using a 4-wire shielded long cable. Some simulation results and experimental validations are included.     

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.     

绕线式异步电动机起动过程仿真研究

比较研究了三相绕线式异步电动机的在线直接起动、转子串可变电阻器起动和定、转子绕组双馈供电起动三种起动方法的起动性能。变转子电阻法是在起动时可变的三相电阻器接入转子电路并假定在起动过程中外接三相电阻可以连续变化以获得最大转矩。定、转子绕组双馈供电起动法是通过在预定的一个短时间内把定、转子绕组同时并联在同一个电源上而实现的。为了得到起动特性,建立了三相异步电动机在(d,q)静止坐标系下的动态数学模型,编制了仿真程序。通过实例对三相绕线式异步电动机的起动过程进行仿真计算,并对仿真结果进行比较分析,得出了一些有用的结论。     

Integral feasible prestress of cable domes

Cable domes, first proposed by Geiger, belong to the indeterminate and prestressed assembly. Thus, the geometric stability analysis and the optimal prestress design are very important to understand the behaviour of cable domes. A new specific equilibrium state of integral feasible prestress is presented in this paper. Applying this specific state, the algorithm of geometric stability analysis of cable domes is modified and the optimal prestress of the domes is also designed. The numerical results show the proposed state of integral feasible prestress is unique to a specific dome and it is therefore useful for further research of cable domes.     

System design and user evaluation of Co-Star: An immersive stereoscopic system for cable harness design

The system design and results of a user evaluation of Co-Star an immersive design system for cable harness design is described. The system used a stereoscopic head mounted graphical display, user motion tracking and hand-gesture controlled interface to enable cable harnesses to be designed using direct 3D user interaction with a product model. In order to determine how such a system interface would be used by a designer and to obtain user feedback on its main features a practical user evaluation was undertaken involving ten participants each completing three cable harness design tasks with the system. All user interactions with the system were recorded in a time stamped log file during each of the tasks, which were also followed by questionnaire (5 point scale) and interview sessions with each participant. The recorded interaction data for the third task was analysed using functional decomposition techniques and used to construct a single activity profile for the task based on the mean results obtained from the participant group. The goal was to identify in general terms the relative distribution of user activity between specific purposes during practical system operation, and it was found that in this task Navigation accounted for 41%, Design 27%, System Operation 23% and looking at Task Instructions 9% of all user activity. The scored questionnaire data collected immediately after the completion of each task was used to rank the major features of the system according to user opinion. This was further enhanced by also collecting real interview comments from the user group about these same features. The combination of both quantitative performance analysis and subjective user opinion data obtained during a practical design exercise has enabled an in depth evaluation of the system, leading to a much greater understanding of many of the key user and interface requirements that should be considered during the development of immersive interfaces and systems for practical engineering applications.     

基于模型的离心泵故障诊断设计

针对离心泵这一工业技术过程中的基本设备,开展基于解析模型的故障诊断方法设计研究。首先在对离心泵工作机理进行详细分析的基础上,建立离心泵管道系统的传递函数模型,然后考虑电动机定子绕组发生匝间短路,建立其在故障情况下的模型。接着,基于所构建的模型,采用因式分解方法设计残差产生器以实时检测匝间短路故障。最后,通过Matlab/Simulink仿真验证了所提方法的有效性和优越性。     

Efficient cable arrangement in cable stayed bridges based on sensitivity analysis of aeroelastic behaviour

Construction of cable supported bridges has experienced a great impulse in the past decade. Bridges having more than 800 m of span length were built in France and Japan and some bridges with span length of more than 1 km are going to be built, such as the Stonecuters bridge in Hong-Kong, and the Chongming in China (Fig. 1). Because of the increasing length of this class of bridges, they are becoming prone to phenomena like flutter in a similar way than long span suspension bridges.

Cable stayed bridges may present a few different alternatives for the cable system. At least harp, fan or modified fan arrangements can be discussed at the beginning of the design. Also variations in the number of cable planes can be studied.

Usually, during the design process changes are made by carrying out a number of analyses and using trial and error techniques relying in heuristic rules that are based upon the particular skills of the engineer. This approach can be inefficient in new problems and commonly it needs to be supported with results coming from experimental testing which makes more expensive the whole design process. Instead of that, an approach based in sensitivity analysis can be very helpful for the designer.     

超声传感器在电机定子局部放电研究中的应用

在利用超声波进行发电机定子绕组局部放电的在线监测中,超声传感器的选型、超声波信号的衰减以及时延性都将影响到在线监测的效果.鉴于此,通过将发电机正常运行时的噪声频谱与局部放电超声信号频谱进行分析对比,并建立定子模型,通过仿真实验获取超声波传播时的声压分布图;再通过实验检测对超声信号在传播过程中的衰减与时延性进行分析研究....     

基于位移控制的线圈自动绕线系统研究

在电磁式力触觉再现系统中,电磁铁线圈绕制质量的好坏直接决定了力触觉再现的真实感和沉浸感。该系统基于手摇绕线机、步进电机、电缸平移台、张力控制器、STM32单片机等模块,设计开发了大尺寸电磁铁线圈自动绕制系统。研究了以STM32为核心的精准排线控制算法,实现了大尺寸空盘片骨架自动绕线排线工作。以实际绕制的线圈为研究对象,通过与人工绕制线圈的效果对比,验证了排线算法的可靠性和稳定性;通过测量线圈的电阻值与理想值的对比,证明了线圈绕制质量的可行性。该系统为大尺寸线圈绕制提供了有效的解决方案,对促进力触觉的发展具有重要的研究意义。