【作者】 原天红；

【导师】 夏加宽；

【作者基本信息】 沈阳工业大学 ， 电机与电器， 2007， 硕士

【摘要】 在大功率电气传动领域，交流传动已取代了直流传动，随着科学技术的发展和生产工艺技术的进步，越来越多的电气传动采用调速技术。同步电机在电气传动中占有很大的比例，传统同步电机的转速是恒定不可调的，在恒频运行下的同步电机存在着启动困难、运行过程易发生失步和振荡的问题，恒频运行的同步电机由励磁调节器来控制电机的启动和失步问题，但能源浪费严重且还不能彻底解决失步问题。国外很多大公司已经深入研究了大型同步电机的变频调速技术，同步电机的励磁调节已经融入了变频器，但它们的变频装置价格昂贵。如果能把价格低廉的通用变频器应用到同步电机的变频调速上，还能解决电机的振荡和失步问题，这是一个很诱人的研究课题。由电机学原理可知：功角δ影响电机的稳定性，δ角就是合成磁势F_μ与激磁磁势F_f之间的角度。如果能检测或计算出功角δ，以至控制功角δ，必能对电机进行调速和解决电机的振荡和失步问题。文章提出了“功角截止负反馈”控制策略来解决电机的调速和失步。“功角截止负反馈”控制策略的关键技术在于如何准确而快速地实现功角估算。本文采用纯电气测量方法，即采集同步电机的输出电压、电流或其他电气量，进而通过理论分析和计算来获得功角。然后提出了基于稳态公式或相量图迭代求解的解决方案，准确而快速地求解出功角。然后，搭建了基于C8051F015单片机的励磁硬件平台，其中包括电流、电压等模拟量的检测与预处理单元、显示和参数输入单元以及变频器的选型，为整个方案的实现提供了物理基础。系统功能的实现，关键在于软件。功角的迭代求解是整个软件的核心，求解的快速性和准确性决定系统性能的好坏。文章完成了软件框图的绘制与软件的编写。最后进行了系统调试，验证了方案的合理性。更多还原

【Abstract】 In the field of high power, AC drive has replaced DC drive and with the progress of the technology and manufacture, more and more electric drive adopts the technology of velocity modulation. Synchronous motors have a large proportion in the electric drive. The velocity of traditional synchronous motor is constant and unmodulated. There are many problems when the synchronous motors operate in the condition of constant frequency, such as the difficulty of startup, outer-sync and agitation in the process of operation, startup and outer-sync of the constantly frequent synchronous motor controlled by excitation controller, but the waste of energy is serious and outer-sync is unthorough settled. Many companies have greatly researched the technology of frequency control of large synchronous motors and excitation regulation of synchronous motors has been applied in frequency-converter, but the plant of frequency conversion is very expensive. The research is very attractive, if the convenient universal frequency-converter can be sued in frequency control of synchronous motor, and the problem of agitation and outer-sync can be settled.From the principle of electoromechanics, it is can be obtained that the power-angle 8 influences the stability of the motor, and the 8 is the angle between the synthrtical magnetic potential F_μand motivative magnetic potential F_f. If the the power-angleδcan be measured or calculated and even can control the power-angleδ, it must can regulate the motor and solve the agitation and outer-sync of the motor. To resolve the speed-regulating and the desynchronizing of the motor, "the power angle cut-off degenerative feedback" control strategy is proposed in this paper.The key technology of the power angle cut-off degenerative feedback" is based on how to estimate the power angle fast and accurately. In this paper, it adopted the pure electric measure method, it collected the output voltage of the synchronous motor, current or any other electric quantity, moreover it obtained the power angle by theory analyze and calculate. Then it proposed the scheme-solving based on steady-state formula or the solution of vectogram iterate, in order to get the power angle fast and accurately.Then, the excitation hardware flat roof with C8051F015 single chip processor is set up, it included the measure and pretreatment cell of the current and voltage analog quantity, the lectotype of display and parameter input cell as well as transducer, it provide the physics basic for the whole project.The soft ware is very important in the realization of system function. The core of the whole soft ware is the iterative solution of the power-angle. The performance of system is determined by the rapidity and the accuracy. The drawing of soft ware block diagram and the writing of the soft ware have been finished in this paper.At last the system is debugged and the rationality of the project is proved.更多还原