电压

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。

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。

Then, in a second interval, the voltage is raised to a second voltage no less than the starting voltage and with an absolute gradient smaller than that for the voltage rise in the first interval.

然后，在第二区间中，电压上升至不小于启动电压的第二电压，并且电压上升的绝对斜率小于在第一区间中电压上升的绝对斜率。

On the base of practical transformer substation main connection, electric components and system circuit model are first formed in the paper; analyze vacuum arc characteristic and medium resume are analyzed, then, according to vacuum chamber physical process of switching AC arc, resume process are divided into three stages: sheath development, neutral particles diffusion and static characteristic, with that, calculating model of medium resume strength is erected and applied in the computing of vacuum circuit breaker interrupting transform overvoltage; In the paper, Saber software is used to simulate a whole switching process; As follows, overvoltage characteristic of vacuum circuit breaker switching no load and load transformers, kinds of influence factors are analyzed in detail; At last, vacuum circuit breaker switching capacitance group overvoltage formative causes and electrode refining for lessening reignition are discuss.

本文针对中低压变电站的实际主接线建立各电气元件及系统的电路模型；在真空电弧的特点及间隙的介质恢复特性上，依据真空断路器灭弧室分断电弧的物理过程，将真空电弧熄灭后的恢复过程分为鞘层发展、中性粒子扩散和静态特性三个阶段，建立了相应的介质恢复强度的计算模型，应用到切除变压器操作过电压的计算中；采用Saber仿真软件模拟计算真空断路器切除变压器操作过电压；并分别对真空断路器切除空载及负载变压器操作过电压的特点与影响操作过电压的各种因素做了详细的分析；最后简要分析了真空断路器开断电容器组过电压的形成原因及为减少重燃的电极老炼措施。

On the base of practical transformer substation main connection,electriccomponents and system circuit model are first formed in the paper;analyze vacuum arccharacteristic and medium resume are analyzed,then,according to vacuum chamberphysical process of switching AC arc,resume process are divided into three stages:sheathdevelopment,neutral particles diffusion and static characteristic,with that,calculatingmodel of medium resume strength is erected and applied in the computing of vacuumcircuit breaker interrupting transform overvoltage;In the paper,Saber software is used tosimulate a whole switching process;As follows,overvoltage characteristic of vacuumcircuit breaker switching no load and load transformers,kinds of influence factors areanalyzed in detail;At last,vacuum circuit breaker switching capacitance groupovervoltage formative causes and electrode refining for lessening reignition are discuss.

本文针对中低压变电站的实际主接线建立各电气元件及系统的电路模型；在真空电弧的特点及间隙的介质恢复特性上，依据真空断路器灭弧室分断电弧的物理过程，将真空电弧熄灭后的恢复过程分为鞘层发展、中性粒子扩散和静态特性三个阶段，建立了相应的介质恢复强度的计算模型，应用到切除变压器作过电压的计算中；采用Saber仿真软件模拟计算真空断路器切除变压器作过电压；并分别对真空断路器切除空载及负载变压器作过电压的特点与影响作过电压的各种因素做了详细的分析；最后简要分析了真空断路器开断电容器组过电压的形成原因及为减少重燃的电极老炼措施。

On the base of practical transformer substation main connection,electriccomponents and system circuit model are first formed in the paper;analyze vacuum arccharacteristic and medium resume are analyzed,then,according to vacuum chamberphysical process of switching AC arc,resume process are divided into three stages:sheathdevelopment,neutral particles diffusion and static characteristic,with that,calculatingmodel of medium resume strength is erected and applied in the computing of vacuumcircuit breaker interrupting transform overvoltage;In the paper,Saber software is used tosimulate a whole switching process;As follows,overvoltage characteristic of vacuumcircuit breaker switching no load and load transformers,kinds of influence factors areanalyzed in detail;At last,vacuum circuit breaker switching capacitance groupovervoltage formative causes and electrode refining for lessening reignition are discuss.

本文针对中低压变电站的实际主接线建立各电气元件及系统的电路模型；在真空电弧的特点及间隙的介质恢复特性上，依据真空断路器灭弧室分断电弧的物理过程，将真空电弧熄灭后的恢复过程分为鞘层发展、中性粒子扩散和静态特性三个阶段，建立了相应的介质恢复强度的计算模型，应用到切除变压器操作过电压的计算中；采用Saber仿真软件模拟计算真空断路器切除变压器操作过电压；并分别对真空断路器切除空载及负载变压器操作过电压的特点与影响操作过电压的各种因素做了详细的分析；最后简要分析了真空断路器开断电容器组过电压的形成原因及为减少重燃的电极老炼措施。

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。

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。

Impact of an operating voltage on impulse over-voltage strength in the transformer is analyzed. Necessity of the operating voltage defined by the test voltage of the lightning impulse for UHV power transformers is pointed out. Through researches the maximum permissible operating voltage for the main isolation of UHV transformers is obtained.

分析了变压器的工作电压对冲击电压强度的影响；指出了雷电冲击试验电压定义下的工作电压对于特高压变压器的必要性；通过研究得出了特高压变压器的主绝缘的最大许用工作电压。

I can not make it blossom and suits me

我不能让树为我开花

When temperatures are above approximately 80 °C discolouration of the raceways or rolling elements is a frequent feature.

当温度高于 80 °C 左右时，滚道或滚动元件褪色是很常见的特征。