| 1. | If the excitation current is too great , adopting dc machine excitation would require more collecting rings 如果励磁电流太大,采用直流机励磁则会引起集电环的对数增多。 |
| 2. | < uk > proof of distributed feedback was the tuning of the laser wavelength over 130 a by changing the grating period , and the absence of shift in wavelength with increasing excitation current . < / uk > < uk >存在分布反馈的证据是,改变光栅周期可使激光波长在130 a范围内变化以及波长不随激发电流的增大而移动。 < / uk > |
| 3. | When generator runs at conversation states from synchronous speed to super - synchronous speed , the excitation current of oppositional phase sequence should ensure the current waveform smoothly transform 当发电机运行于同步速向超同步速过渡转换状态时,需向转子馈入反相序的励磁电流,且保证励磁电流的波形平滑连续。 |
| 4. | Exactly measuring parameter in doubly - fed machine adjustable speed system , the system with closed loop control improves the capability of this experiment system . by controlling excitation current of the rotor , the control technique can realize speed adjustment 系统对双馈电机调速时所用到的参数进行了准确的测量,并实现了闭环控制,提高了系统的性能。 |
| 5. | When the system is working , the photoelectric coder checks the speed of doubly - fed vscf wind power generator ; according as the principle formula of vscf , the excitation current frequency of rotor is calculated to satisfy the aim of vscf control 系统工作时,用光电编码器检测出发电机的转速,依据变速恒频的原理公式计算出应馈入转子励磁电流的频率,达到变速恒频控制的目的。 |
| 6. | Second , a doubly salient electro - magnetic generator employs two independent channels consisting of two groups three phase windings . the two channels provid power to the same load and output voltage can reach the demand through adjusting the excitation current 文中还在一台电励磁双凸极发电机的定子上设置两套3相电枢绕组,实现双通道发电,通过调节励磁电流大小使两发电通道输出相应的额定电压,并联向负载供电。 |
| 7. | Design the configuration parameter of the electromagnets using magnetic circuit theory , and check the temperature increase of the electromagnet . and design a power device using igbt with electric and electron theory . it can supply the electromagnets excitation current which changes regularly on a given rule 对于弯扭矩检测系统,运用应变仪的原理,在试件上的合适位置加贴应变片并组成惠斯登全桥差动电路,检测出实际加载在试件上的弯矩和扭矩的大小。 |
| 8. | 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。 |
| 9. | In this method , the similar inductance is used to extract the excitation current of ct , which , through some electronic circuits , turns into proper compensation current and is injected into the compensation winding . this current replaces the exciting current , so the error is reduced 本文的实现方法是采用具有与电流互感器铁芯相似磁特性的铁芯制成的电感提取电流互感器的励磁电流,将该励磁电流经过一些电子电路的处理,产生补偿电流,注入补偿绕组,从而减小电流互感器的误差。 |
| 10. | This dissertation firstly expounds the basic principle and electric structure of astg , and analyzes the principle of excitation control . because in actual system the excitation current is always the control target , the mathematical model with excitation - current controlled , which can be referenced by simulation of the same type system , is put forward 本文首先介绍了异步化汽轮发电机的基本原理和电气结构,深入分析了异步化汽轮发电机的励磁控制原理,由于实际的励磁装置大多以励磁电流为被控制量,提出了异步化汽轮发电机转子励磁电流控制的数学模型。 |