定子电流

• Using stable heat transferring theory , a thermo hydraulic model has been built , which has considered the influence of the core temperature and cooling hydrogen temperature . and bring forward a modifying method , which let the model can be used in the varying winding current condition
  在此基础上本文提出了温度传递延时的修正方法，使基于稳态传热的温度水力模型可以应用到定子电流发生变化的情况，解决了定子电流变化时模型精度差的问题。
• After studying a lot of documents , we present a speed - estimating method for direct torque control system . this method is based on the theory of dtc , but it takes advantage of the convenient of both the theory of dtc and the theory of foc . we need only to sample the stator ' s current to estimate the speed of the rotor , at the same time the integration of the voltage is avoided
  在研究大量文献的基础上提出了一种适用于交流电机dtc控制系统的转速计算方法，该方法以dtc控制为中心，结合dtc和定子磁场定向和转子磁场定向各自的特点，综合利用各自的有利之处，只需测量定子电流，避免了对电压积分，思路清晰，计算简单。
• Just using the stator currents , stator voltages , and velocity , the method proposed in the paper makes real time identification of induction motor parameters based on the least squares identification algorithm . the method does n ' t use the rotor flux signal , avoiding the coupling between the rotor flux observation and the parameter identification
  本文提出仅用电机的定子电流、电压和转速进行电机参数的辨识方法，它利用递推最小二乘法进行在线参数辨识，该方法不需要观测得到的磁链信号，消除了磁链观测和参数辨识的耦合。
• In engineering , vector control ( vc ) is called as filed orientation control ( foc ) . the principle of foc is to divide stator current into two dc components . one of them is oriented to the rotor magnetic flux , another is oriented to the torque . the operating process can be carried out by transforming coordinate in magnitude flux and torque keeping consistent conditions
  矢量控制一般称为磁场定向控制，该控制理论的原理是在转子磁通和转矩保持不变的情况下通过坐标变换将异步电机的定子电流分解为按转子磁场定向的两个分量分别进行控制，从而实现转子磁通和转矩的解耦。
• We discuss the influence on the flux and torque when the multi - voltage space vector is applied on the motor . then the strategy of producing hexagon flux or circle flux is proposed . it is believed that , in order to control the torque optimally in dtc system , the stator current needs to be observed predictably
  论文在阐述异步电动机的直接转矩控制原理的基础上，详细分析了多电压空间矢量对磁链和转矩的影响，给出了六边形磁链和圆形磁链以及定子电流预测的设计方法，提出了一种新的转速环控制方法。
• 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。
• To achieve it the author established a new observation flux linkage based on mras ( model reference adaptive system ) , which choose the stator current as comparing signal and can effectively estimate the flux linkage and rotate speed with simple configuration . the speed estimation with speed sensorless is an important trend of modern ac drive
  对磁链的观测采取了改进的u - i积分器,并提出了一种新型的定子磁链mras自适应观测器,以定子电流作为比较信号,结构简单,能有效地辨识定子电阻,从而真正有效地估计定子磁链和速度。
• Some research about sensorless control of induction motors in recent years has been introduced in chapter one . in chapter two , a field - oriented control system with current regulator and voltage source inverter ( vsi ) is presented firstly , which is proved in theory that the voltage feed - forward decoupler can be omitted , the good decoupled control properties of flux current and torque current is also validated by experiments with speed - sensor based on f240dsp real system
  论文第二章从异步电机的基本数学模型入手，介绍了一种基于转子磁场定向的带电流内环控制的电压型逆变器输出闭环矢量控制结构，在理论上证明了该模型可省略电压前馈解耦环节，采用f240dsp芯片构建的带速度传感器实验系统验证了其定子电流励磁分量和转矩分量有良好的解耦控制特性。
• In this paper , several scheme of vscf is compared firstly , of which gets doubly - fed generating mode . doubly - fed vscf wind power generating system uses a doubly - fed induction generator , which rotate speed can be able to change with wind turbine , and it ensures a constant - frequency output , by controlling the frequency of current input into rotor windings . in vector trans control system , the control of stator active power and the control of stator reactive power can be essentially decoupled , and the former is via torque component and the latter is via exciting component of stator current
  本文首先比较了几种变速恒频方案，从中选择了双馈式变速恒频方案；它运用双馈电机的工作原理，允许发电机转速变化，而在电机转子侧接入低频励磁电流，通过控制该电流的频率，保证双馈电机定子输出的频率恒定；再结合矢量控制技术，通过调节转子电流来控制定子电流的转矩分量和励磁分量，相应独立地控制发电机输出的有功功率和无功功率。