查询词典 excitation voltage

The conditions of self - excitation and the influence of automatic voltage regulator on power system self-excitation are analyzed and the system reaponse characteristics of power system under self-excitation are summarized.

分析了电力系统自激的产生条件及励磁调节器对自激的影响，研究了自激发生后系统的动态过程，提出了以发电机机端电压、发电机转子角速度以及励磁电流这3个量的变化规律作为判断复杂电力系统发生自激的依据，并以一个典型的双机系统的仿真结果验证了判据的有效性。

Our main products are: microprocessor-based arc, harmonic elimination and PT counters, high-capacity three-phase modular overvoltage protectors, Intelligent Switchgear control devices (SC-8), current mutual inductance Secondary over-voltage protectors, large-capacity high-speed switching device, de-excitation of synchronous generator rotor Switchgear, composite over-voltage protectors, low-voltage modular overvoltage protectors ( SCB-400), high voltage current-limiting fuse combination switch cabinet, computer integrated protection device and other products.

公司主要产品有：微机型消弧、消谐及PT柜、高能容三相组合式过电压保护器、开关柜智能操控装置（SC-8）、电流互感器二次过电压保护器、大容量高速开关装置、同步发电机转子灭磁开关柜、复合式过电压保护器、低压组合式过电压保护器（SCB-400）、高压限流熔断器组合开关柜、微机综合保护装置等产品。

There are some important and novel conclusions deduced: 1. The curve of resonance output vs excitation voltage shows that electrostatically excited resonator could be easily excited by low excitation voltage and could be well protected when overloaded due to the good structure design.

静电激励微谐振器谐振峰值与交流激励电压的关系曲线表明该谐振器在较低的电压激励下即可获得较大的振幅，同时该谐振器具有良好的过载保护功能，在用于精确测量时，必须保证激励电压处于该曲线的线性段。

Secondly, the discharge characteristics were investigated. As the RF power was switched on and the matching impedance suitably set, a pale-purple glow was initially generated near the wall. With increasing RF power, the pale glow evolved into bright white glow. Analysis of voltage and current wave forms suggested that both the voltage and current wave forms are predominately sinusoidal and discharge cycle was above 100 nanoseconds. Current-voltage curve showed that discharge current increase as voltage increase without any abrupt; The current-voltage phase angle suggested that the plasma evolved from being predominately capacitive to predominately resistive. Discharge mode was essential an abnormal glow discharge plasma.

其次对装置的放电特性进行了分析，从放电的现象看，随着放电功率的提高，放电颜色由开始的暗紫色过渡到亮白色；从电流-电压波形曲线图发现所有的放电电流和电压曲线都是正弦曲线，放电的周期达到上百个纳秒；从电流—电压曲线分析，电流随着电压的增长而增长，并没有发现任何的突变现象；从电压—电流相位角来看，随着电流的增大，相位角基本保持不变，整个电路表现出容性放电性质，但是电阻性成分已经很强，属于反常辉光放电区域。

However, since high-fiber makes transmission insulated between the high-voltage and low-voltage, there isn't any electromagnetic contact between the high-voltage and low-voltage. So, how to supply power for high-voltage circuits become pivotal technology, which is difficulty in research technology.

但由于采用光纤传输使高低压绝缘隔离，高低压之间没有任何电磁联系，因此如何向有源ECT高压侧电路供电就成为一项关键的技术，是研制中的技术难点。

The invention discloses a DC/DC circuit, comprising a PWM controller, a current amplifier, a peak current comparator, an error amplifier, a main switch, a synchronous switch and also an operational amplifier. The non inverting input end of the operational amplifier is used for coupling with input voltage or voltage reference, or used for coupling with the input voltage and the voltage reference; the inverting input end of the operational amplifier is used for coupling with the voltage reference or ground, and the output end thereof is connected with the non inverting input end of the error amplifier.

本发明公开了一种DC/DC电路，包括PWM控制器、电流放大器、峰值电流比较器、误差放大器、主开关和同步开关；还增设运算放大器，其同相输入端用于与输入电压或基准电压耦合，或用于同时与输入电压和基准电压耦合；其反相输入端用于与基准电压或地耦合，其输出端与所述误差放大器的同相输入端连接。

The relationship between minimal model characteristic value of electric power system tie flow Jacobin matrix and voltage steady-state stability is was discussed, and the minimal model eigenvalue is was defined as voltage stability abundant degree. On this foundation, the sensitivity of voltage stability abundant degree to control variables and to PQ point load are was defined in order to seek the factors of impacting voltage stability and explore the voltage weak point, and give out their algorithm simultaneously.

讨论了电力系统潮流雅可比矩阵最小模特征值与系统电压静态稳定性的关系，将最小模特征值定义为电压稳定裕度，在此基础上定义了电压稳定裕度对控制变量的灵敏度和PQ节点负荷灵敏度，用以找出对系统电压稳定性造成影响的因素和寻找系统电压薄弱点，同时给出了它们的算法。

For improve altogether mould inhibit than,in before the high altogether mould inhibit output altogether mould voltage feedback to shouldering by ends public of power also among the amplifiers than instrument in grade, make it put power voltage until mould input voltage float , setover voltage follow mould inputs the voltage into together very much each altogether not to transport, thus improved together mould inhibit to.

为提高共模抑制比，在前级高共模抑制比仪器放大器中还将输出共模电压反馈到正负电源的公共端，使运放电源电压随共模输入电压浮动，各极偏置电压都跟踪共模输入电压，从而提高了共模抑制比。

The variables in controlling the flow of microfluids are voltage and time. This study adopted the method of fast measurements、so time taken for applying voltage did not exceed ten minutes. If voltage is not carefully controlled、the microchannel may be damaged at the particle flow. During measurement、a buffer fluid with a concentration of 0.1 M was used、the current was sufficient to propel the magnetic particles through the microchannel without damage from excessive voltage. The maximal amount of microfluid particles at the junction of the separation and injection channels was obtained with a time of 5 mintures and voltage of 200V.

藉由改变不同的电压和时间来观察颗粒在微流体中的移动情形，由於这个研究是以快速检测为原则，所以将时间控制在10分钟之内；在电压的控制上面如果电压太大的话将会对微流体的管道造成损伤，降低微流体装置的寿命，并且也有可能会对里面的颗粒造成影响，所以缓冲液的浓度使用比较大的0.1 M，这样所产生的电流将足以推动磁性颗粒并且电压不会太大也不会造成管壁的伤害。

Through the analysis of the work principle of three phases voltage resource PWM converter, set up the low and high mathematic models, deduce the restriction equations about grid voltage, grid current, modulation voltage and the DC output voltage and the calculation equations of the AC-side inductance and the DC-side capacitance. There are two control strategies are adopted: Predicted current control strategy and voltage-current two closed-loop control strategy, and give a comparison by theory and practice.

通过分析三相电压源型PWM变换器的工作原理，分别分析了低频和高频数学模型，并推导出了交流侧电压电流、调制电压、直流侧电压之间的数学约束关系以及交流侧电感和直流支撑电容参数的选取依据公式；分析对比了两种控制策略：预测电流控制和电压电流双闭环控制并加以实验验证；同时采用了负载电流前馈补偿和本文提出的一种基于专家系统的神经元新型智能PI控制器两种方法大大提高了整个系统的动态响应性能，并在仿真和实验中加以验证，这也是本文研究的重点内容之一。

"Bird Man's Diary, Butting on the Love Island", Changsha, China

2008年"鸟人日记，顶在爱情岛"，中国长沙

As long as they were in the service of a family of wizards, their magic would remain dormant.

只要他们一天为家庭服务，他们的法力就潜藏不动。