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和断路器有关的一段翻译啊，哪位好心人帮帮忙吧，我把所有的金币都给你啦~~
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Power circuit breakers play the most important role in pre- serving the stability of power networks and in decreasing the induced damages to power system utilities in the case of any fault. Therefore, the determination of their interruption capability limits seems to be necessary to be able to predict whether different faults can be cleared. Most of failures occur in gas circuit breakers originate from a soft thermal collapse of the gas insulation within less than microsecond after cur- rent zero; the so-called thermal reignition, due to the increase in the conductivity of the rest plasma resulted from the flowof the post-arc current produced by application of the initial transient recovery voltage to the breaker. The density of the rest plasma is dependent on the cur- rent fall rate before current zero, and the post-arc current responsible for heating up the plasma is controlled by the conductivity of the rest plasma and the applied voltage. So, it can be concluded that the thermal reignition is strongly dependent on the rate of decrease in the current before cur- rent zero as well as on the rate of increase in the recovery voltage [1, 2]. As the result to evaluate the limits of the interruption capability of the circuit breakers, different currents and voltage have to be applied to the circuit breaker. Some efforts have been accomplished to perform some test related to thermal reignition using a full synthetic test method [3, 4]. In some other studies, a characteristic of the interruption capability in terms of the time derivative of the current and rate of increase in the applied voltage has been established [5, 6]. The presence of an auxiliary breaker (AB) in a synthetic circuit is unavoidable. As the AB opens during the current flow through the test breaker, the voltage of the high current source is divided between AB and test breaker resulting in a reduction of the arc energy in test breaker as addressed in [7]. Also the distortion of the current waveshape near cur- rent zero makes the evaluation of the limits of the thermal interruption capability of the circuit breakers erroneous. |
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lxuyan
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sirljz(金币+3):谢谢交流 2010-05-01 22:26
tea0sky(金币+1, 翻译EPI+1):谢谢你啦~ 2010-05-02 10:12
sirljz(金币+3):谢谢交流 2010-05-01 22:26
tea0sky(金币+1, 翻译EPI+1):谢谢你啦~ 2010-05-02 10:12
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电源断路器在电网的稳定性方面和降低引起损害的电力系统的故障方面，扮演着很重要的作用。因此,检测其中断容量的限制范围似乎是很有必要的,能用来预测是否可以修复不同的电路故障。大多数故障发生在天然气断路器，它在电流为零后微秒级之内会伴随着一个柔软的气体绝缘导热体的坍塌;所谓的热再引弧电压,是由于导电性的等离子体而产生的弧后电流流量，导致所产生的瞬态恢复应用的电压开关。 剩余的等离子体密度取决于电流在变成0之前的电流降低速率。还有可以通过控制剩余等离子体和外加电压的导电性来实现弧后电流对等离子的升温。所以,我们可以得出这样的结论：热再引弧依赖于在电流变成0之前的电流的降低速率和电压的恢复速率[1,2]。 所以，为了评估断路器的极限，必须用不同电流和电压来试验这个断路器。某些人已经努力完成了这样的工作，用全人工综合测试方法来检测一些关于再引弧电压的试验[3，4]。还有人建立了一个模型，关于电流的时间导数和外加电压的增加速率来描述断路器的特性[5,6]。如文献[7]所述，辅助开关(AB)在一个综合电路中是不可缺少的。因为AB可以通过测试断路器来控制电流流量，而且高电流源的电压可以平均分配在AB和测试断路器间，所以可以在测试断路器的时候来降低电弧能量。在电流接近0时，失真电流波形可以评估电路断路器错误的热熔断的极限范围。 [ Last edited by lxuyan on 2010-5-1 at 17:58 ] |
2楼2010-05-01 17:25:39
