共查询到19条相似文献,搜索用时 109 毫秒
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研究了超高功率电弧炉对电网的影响以及抑制方法,分析了电弧炉的功率因数低、电压闪变和波动、负序电压等不利影响,并探讨了静止型无功补偿装置在电弧炉补偿中的应用。针对电压波动值和补偿容量的计算,提供了相应的计算公式。在电弧炉参数、供电设备和电源改进方面,讨论了预热废钢料、破碎工艺和喷吹辅助燃料等措施。此外,介绍了配电用静止补偿器和有源滤波器的工作原理和优势。强调了电网电能质量管理的重要性,并展望了未来的发展趋势。研究结果对电网稳定性和电弧炉运行具有重要的参考价值。 相似文献
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介绍了有载调压变压器的调压原理与作用,电压的稳定性和电压崩溃的原因,阐述了自动调压的优缺点,重点分析了自动调压对电力系统电压稳定性的影响,并提出了相应的技术措施。 相似文献
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电压稳定性是指电力系统维持电压的能力。电力系统各母线电压在正常和受扰动后的动态过程中被控制在额定电压的允许偏差范围内的能力。电压稳定性又分为幅值稳定性与波形稳定性两方面。通常以电压偏差、电压波动与闪变、电压正弦波畸变率、频率偏差等项指标来衡量。 相似文献
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电力系统电压稳定是电力系统稳定性的重要研究方向之一,本丈首先介绍了IEEE/CIGRE关于电压稳定性的定义与分类,然后具体阐述了静态电压稳定方面关于利用灵敏度信息来判别系统是否稳定的方法,最后指出灵敏度信息还存在的不足之处. 相似文献
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介绍了一种简单实用的蓄电池充电技术。充电电压始终跟随蓄电池电压变化,并保持一恒定差值。在达到蓄电池额定电压后转化为恒压充电方式。这样既能较快地对蓄电池充电,还不会因初期充电电流太大损坏蓄电池极板,同时也减少了电源的能耗。 相似文献
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重点介绍XHG消弧柜限制弧光接地过电压的工作原理,及与传统消弧线圈限制弧光接地过电压所表现的不同特点及优点。 相似文献
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根据化合物单相嵌锂时的晶体结构和嵌锂能的变化特征,采用热力学和统计物理的分析方法,推导了任意嵌入式化合物的嵌锂电压的表达式。对该式中各参数的分析表明:嵌锂电压主要取决于空位嵌锂能,嵌锂过程中的组态熵的变化对电压的贡献较小;已嵌入的锂离子及其邻近阳离子的还原所导致的嵌锂能的变化是影响电压平稳性的关键因素。 相似文献
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Recently the compensator has been shown to be an in expensive and reliable dose delivery device for photon beam intensity-modulated radiation therapy (IMRT). The goal of IMRT compensator design is to produce an optimized primary fluence profile at the patient's surface obtained from the optimization procedure. In this paper some of the problems associated with IMRT compensator design, specifically the beam perturbations caused by the compensator, are discussed. A simple formula is derived to calculate the optimal compensator thickness profile from an optimized primary fluence profile. The change of characteristics of a 6 MV beam caused by the introduction of cerrobend compensators in the beam is investigated using OMEGA Monte Carlo codes. It is found that the compensator significantly changes the energy spectrum and the mean energy of the primary photons at the patient's surface. However, beam hardening does not have as significant an effect on the percent depth dose as it does on the energy spectrum. We conclude that in most situations the beam hardening effect can be ignored during compensator design and dose calculation. The influence of the compensator on the contaminant electron buildup dose is found to be small and independent of the compensator thickness of interest. Therefore, it can be ignored in the compensator design and included as a correction into the final dose distribution. The scattered photons from the compensator are found to have no effect on the surface dose. These photons produce a uniform low fluence distribution at the patient's surface, which is independent of compensator shape. This is also true for very large fields and extremely asymmetric and nonuniform compensator thickness profiles. Compared to the primary photons, the scattered photons have much larger angular spread and similar energy spectrum at the patient's surface. These characteristics allow the compensator thickness profile and the dose distribution to be calculated from the optimized fluence profile of primary photons, without considering the scattered photons. 相似文献
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高压变频调速技术在风机、泵类应用中的节能分析 总被引:1,自引:0,他引:1
着重介绍了高压变频器在风机、泵类设备中节能情况,对其节电情况进行分析.结果表明,风机、泵类设备采用高压变频器进行调速节能改造,具有投资省,见效快等特点. 相似文献