| 1. | Locked rotor current 锁定转子电流 |
| 2. | Computation is eased by the law as the rotor current observer is needless under this way 该控制律无需对转子电流进行观测,减少了计算量。 |
| 3. | The paper gives the vector control speed system of the double - fed machine on the rotor current orientation 在进行定子磁场定向后,保持转子电流与定子磁链相垂直,进行转子电流定向。 |
| 4. | In this paper , a direct method based on fixing the rotor current is proposed . by the experiment , we can prove that the method is correct 本论文提出了转子电流定向的速度辨识方法,并且通过仿真、实验研究验证了本方法的正确性及实际的可行性。 |
| 5. | As the rotor of the linear synchronous motor , the suspending electromagnetic irons are excited by rotor current and act with the long stator railway mutually . they have multiform functions such as suspending , advancing and generating electricity 悬浮电磁铁作为直线同步电机的次级,在绕组电流的激励下,与长定子轨道相互作用,同时具备悬浮、推进、发电等多项功能。 |
| 6. | Based on the analysis of the control theory of the dtc of doubly fed induction machines , in this paper , two control schemes are proposed : the least mode of rotor current and the stator power factor adjustable mode . in the first control scheme , we may make the rotor voltage the same or opposite phase with the rotor current by throwing suitable rotor voltage vector 在第一种控制方案中,通过施加转子电压矢量,使转子电流与转子磁链垂直,转子励磁全靠定子电流,即可保证转子电流和转子电压同相或反相,从而实现了转子侧功率因数为1 ,可减小转子侧变频器的容量。 |
| 7. | Simulations for these two conditions prove validity of theoretical analysis . on the basis of this scheme , a new speed adjustment strategy about vector control of doubly fed motor based on rotor current vector fixing is given . it introduces the closed - loop of stator excitation current to the system , which increases two adjustment channels : speed and excitation adjustment 经理论分析可知,该方案中,由于转子电流与磁链无法实现完全解耦,故仅在亚同步工况下有效,在超同步时则会因为调速系统不能自动校正转子磁链幅值变化引起的横向电流而使系统失去控制,无法达到稳定状态。 |
| 8. | The contributions done are as follows : according to the mathematical model of doubly fed motor and the theory of vector control , a unit power factor of rotor control scheme is proposed . in the doubly fed adjustment system , in order to control magnetic torque of motor this scheme is designed by controlling the reverse direction between rotor voltage and current to keep the vertical direction between rotor current and flux . it is known from theoretical analysis that for partly decoupling this scheme is only effective under sub - synchronization speed , but not control the system and obtain steady state since speed adjustment system ca n ' t adjust the magnitude of rotor flux under sup - synchronization 而传统的无速度传感器双馈调速矢量控制系统,由于采用磁链定向方法,在同步速附近存在较大的工作死区,针对上述问题,本文做了如下的研究工作:本文从双馈电机的数学模型出发,根据矢量控制的基本原理,提出了一种转子侧功率因数为1的双馈电机矢量控制方案的设想,即在双馈调速时采用转子电流定向的方法,并控制外加转子电压与转子电流始终反相,以保持了转子电流与转子磁链矢量垂直,通过控制转子电流的大小来达到控制电机电磁转矩的要求。 |
| 9. | This strategy has many advantages : solving the problems that the system is unsteady under super - synchronization ; improving power factor of stator ( it is unity relative to that of rotor ) ; no rotor position sensor and no initial position measurement , easily building up doubly fed speed adjustment system with speed sensorless because adjusting speed is taken in the rotor coordinate and rotor current vector fixing is implemented 该方案由于引入了定子电流励磁分量的闭环控制,使系统同时具有转速和励磁调节两个调节通道,具有如下优点:一、解决了超同步工作工况不稳定的问题;二、提高了定子侧的功率因数(与转子侧功率因数为1相比) 。三、由于速度调节在转子坐标系下进行,并以转子电流矢量定向,所以无须转子位置传感器,也不用检测初始位置,易于组成无速度传感器双馈调速系统。 |
| 10. | The steady state and transient characteristics of the aceg system are simulated , the harmonics of the emf and stator current and rotor current as well as mc ' s input current are researched . the operation characteristics of aceg with mc as an exciter are compared to those of aceg with ac - dc - ac converter and cycloconverter as an exciter . the results in this thesis will be helpful to the design of the aceg excitation control system 利用所建模型,对交流励磁发电机系统的稳态调节特性、暂态特性进行了仿真研究;仿真研究了发电机定、转子电流和感应电势及变频器输入电流波形,并作了相应的谐波分析;与交-直-交变频器和交-交变频器作励磁电源时发电机的运行特性进行了对比分析。 |