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无油自复中调速器在大型水电机组上的试运行及调试 被引量:7
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作者 向家安 李红 张新华 《水电自动化与大坝监测》 2005年第4期16-18,共3页
介绍了无油自复中电/机调速器的机械原理和电气原理,并对其实际运行在大型水电机组上的试验结果进行了分析,证明其在250MW机组上运行的可行性。
关键词 水电机组 调速器 无油自复中 伺服电机 驱动器
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西霞院自复中微机调速器的原理及应用
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作者 张丹 王忠强 +1 位作者 张志勇 胡会永 《科技信息》 2007年第32期90-90,140,共2页
本文介绍了自复中微机调速器的机械原理及电气原理,并对其在西霞院电站的现场投运情况进行了分析和探讨。
关键词 自复中调速器 原理 现场投运
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自复中伺服电机调速器在铜街子水电站中的运用 被引量:2
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作者 刘志华 《四川水力发电》 2008年第A02期68-70,共3页
铜街子水电站调速器由于存在问题,不能满足机组远方监控的需要,通过对PLC自复中可编程调速器进行改造后,因该调速器具有结构简单、维护工作量小、可靠性高等优点,显示出良好的发展前景,定将被广泛应用和推广。重点对该调速器结构特点、... 铜街子水电站调速器由于存在问题,不能满足机组远方监控的需要,通过对PLC自复中可编程调速器进行改造后,因该调速器具有结构简单、维护工作量小、可靠性高等优点,显示出良好的发展前景,定将被广泛应用和推广。重点对该调速器结构特点、动作原理、主要功能,改造后遇到问题与解决办法进行了介绍,希望对其它电厂调速器改造具有一定的借鉴作用。 展开更多
关键词 调速器 铜街子水电站 PLC自复中 改造运用
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自复中调速器在高水头高转速机组上的应用 被引量:1
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作者 白奎明 《水电自动化与大坝监测》 2007年第3期25-26,30,共3页
简要介绍了自复中电/机调速器的机械和电气原理,并就使用该调速器的机组在生产运行中容易出现的停机后导叶开度漂移、停机时导叶不能完全关闭和显示开度与实际开度不一致等主要问题,通过修改可编程逻辑控制器(PLC)程序、调节调零杆位置... 简要介绍了自复中电/机调速器的机械和电气原理,并就使用该调速器的机组在生产运行中容易出现的停机后导叶开度漂移、停机时导叶不能完全关闭和显示开度与实际开度不一致等主要问题,通过修改可编程逻辑控制器(PLC)程序、调节调零杆位置、修改PLC程序参数等方法进行解决,这些方法对同类水电厂处理类似问题有借鉴作用。 展开更多
关键词 自复中调速器 伺服电机 驱动器 水电机组
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无油步进式调速器在水电站的应用
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作者 郭艳艳 雄艳霞 《水电站机电技术》 2006年第4期19-22,共4页
自动复中无油高精度步进电-位移转换器采用步进电机和高精度大导程滚珠丝杆付来完成电/机转换的任务,并用一根压缩弹簧和两个托环来执行在异常情况下供电电源消失或控制信号消失时,自动准确回到中间位置使主配引导阀活塞及主配压复中... 自动复中无油高精度步进电-位移转换器采用步进电机和高精度大导程滚珠丝杆付来完成电/机转换的任务,并用一根压缩弹簧和两个托环来执行在异常情况下供电电源消失或控制信号消失时,自动准确回到中间位置使主配引导阀活塞及主配压复中的任务。本文详细介绍了该装置的机械结构和电气原理,并对其实际运行在马房水电站机组上的试验结果进行分析。 展开更多
关键词 水轮机调速器 无油自复中 伺服电机 驱动器
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FC型主配压阀在若水电站的改造与应用 被引量:3
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作者 杨建伟 廖润 邵建林 《水电站机电技术》 2016年第2期17-19,共3页
近年来,美国GE公司生产的FC型主配压阀在大型及特大型机组调速器中广泛应用。为满足若水电站的设计要求,我们结合FC型主配压阀的结构特点,对分段关闭装置进行改造,以增加纯手动操作和自复中功能。其理念与方法可供其他电站引用参考。
关键词 FC型主配压阀 分段关闭 手动操作 自复中功能
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乐滩水电站调速器机械液压系统改造 被引量:1
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作者 林成海 《广西水利水电》 2009年第1期74-76,共3页
介绍了乐滩水电站单比例阀控制的调速器机械液压系统改造措施,改造后的调速器解决了原调速器卡阻和窜油现象。带自复中功能的比例阀控制系统可保证在调速器比例阀失去外部控制信号和电源时无扰动地切换至自复中控制回路,从而保持失电或... 介绍了乐滩水电站单比例阀控制的调速器机械液压系统改造措施,改造后的调速器解决了原调速器卡阻和窜油现象。带自复中功能的比例阀控制系统可保证在调速器比例阀失去外部控制信号和电源时无扰动地切换至自复中控制回路,从而保持失电或者切换前的接力器开度值。改造后的调速系统静特性、动特性、稳定性等参数均满足或优于规范要求。 展开更多
关键词 调速器 机械液压系统 比例阀 自复中 乐滩水电站
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乐滩电站调速器系统介绍
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作者 林成海 《大电机技术》 北大核心 2010年第3期61-64,共4页
介绍了乐滩电站改造后的调速器机械液压系统工作原理和电气智能控制功能。改造后的调速器解决了原调速器卡阻和窜油现象。带自复中功能的比例阀控制系统可保证在调速器比例阀失去外部控制信号和电源时无扰动地切换至自复中控制回路,从... 介绍了乐滩电站改造后的调速器机械液压系统工作原理和电气智能控制功能。改造后的调速器解决了原调速器卡阻和窜油现象。带自复中功能的比例阀控制系统可保证在调速器比例阀失去外部控制信号和电源时无扰动地切换至自复中控制回路,从而保持住失电或者切换前的接力器开度值。电气智能控制功能使调速器在多种工况下以相应的最优参数和最佳控制结构参与机组的动态调控,并实现不同结构和参数下的平滑过渡。自适应式变参数控制方式解决了原调速器功率调节时波动幅度大的问题。改造后的调速系统静特性、动特性、稳定性等特性参数均满足或优于国标要求,可靠性也有很大提高。 展开更多
关键词 调速器 比例阀 自复中 自适应调节 智能控制
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浅谈双反馈定位式调速器在水电厂的应用
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作者 夏忠林 肖仰国 杨双 《中国设备工程》 2021年第13期155-156,共2页
随着水电行业的发展,特别是大型、特大型水轮机的出现,对水轮机调速器提出了更高的要求,除要求可靠性更高外,还要求静、动态指标优越,否则,出现故障,其损失难以估算。由于我国水电厂液压设备的油质清洁度难以保证,造成先导控制级易发卡... 随着水电行业的发展,特别是大型、特大型水轮机的出现,对水轮机调速器提出了更高的要求,除要求可靠性更高外,还要求静、动态指标优越,否则,出现故障,其损失难以估算。由于我国水电厂液压设备的油质清洁度难以保证,造成先导控制级易发卡;特大型水轮机组惯性大,因此,提高调速器先导级的响应速度,对整机的速动性作用不大。要提高整个系统的动态响应速度,主要是提高主配压阀控制的主接力器的响应速度。 展开更多
关键词 水电厂 调速器 双反馈 伺服比例阀 液压自复中
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无油步进式调速器在草头坪电厂的应用
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作者 龚珍秀 李金保 《科技与企业》 2011年第10X期95-95,97,共2页
简要介绍了BWST步进式可编程微机调速器的设备配置情况、性能特点、调节原理及应用。
关键词 调速器 性能特点 自复中装置 无油电转
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关于调速器系统主配压阀的改进分析
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作者 太军波 陈伟 《水电站机电技术》 2022年第4期103-105,共3页
某电厂原有调速器主配压阀为掉电自复中式,断电后导叶保持不动,同时调速器系统还存在一些需要进一步改进和优化的问题:事故配压阀和紧急停机电磁阀同时动作时关机速度加快,导致蜗壳水压异常上升;主配压阀内漏情况较严重;主配动作时,管... 某电厂原有调速器主配压阀为掉电自复中式,断电后导叶保持不动,同时调速器系统还存在一些需要进一步改进和优化的问题:事故配压阀和紧急停机电磁阀同时动作时关机速度加快,导致蜗壳水压异常上升;主配压阀内漏情况较严重;主配动作时,管道振动较大等。为提高机组运行的安全性和可靠性,对现有调速器系统进行了升级改造。文章主要针对改造后调速器系统主配压阀的“失电动作”进行详细的介绍。 展开更多
关键词 调速器系统 主配压阀 自复中 失电动作
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Rules of variation in hydrogen during reignition of underground fire zones of spontaneous coal combustion 被引量:4
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作者 ZHOU Fubao LI Jinhai LIU Yusheng SHAO He 《Mining Science and Technology》 EI CAS 2010年第4期499-503,共5页
In light of the possibility of reignition when unsealing the closed fire zones, the occurrence of reignition was simulated by a home-made experimental device, hydrogen variety rule from combustion to unsealing was ana... In light of the possibility of reignition when unsealing the closed fire zones, the occurrence of reignition was simulated by a home-made experimental device, hydrogen variety rule from combustion to unsealing was analyzed, the three-stage generation model of hydrogen during reignition in fire zone was put forward and the probability that hydrogen was taken as an indicator gas was discussed. The results show that: when fire zone is ready to unseal, which is filled with hydrogen at a high concentration, it is more prone to reignite. 展开更多
关键词 unsealing fire zone REIGNITION HYDROGEN generation model indicator gas
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Soil Fertility Self-development Under Ecological Restoration in the Zhuxi Watershed in the Red Soil Hilly Region of China 被引量:8
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作者 BAI Li-yue CHEN Zhi-qiang CHEN Zhi-biao 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1231-1241,共11页
Current methods that utilize simple data or models to judge whether soil fertility can selfdevelop are not sufficiently rigorous. A new framework has been set up using catastrophe theory, laboratory experiment, field ... Current methods that utilize simple data or models to judge whether soil fertility can selfdevelop are not sufficiently rigorous. A new framework has been set up using catastrophe theory, laboratory experiment, field work, and 3S(Geographic information system, Global positioning system, and Remote sensing) to explore soil fertility catastrophe under ecological restoration, discriminate whether soil fertility can self-develop, and propose adjustment of ecological restoration measures in the Zhuxi watershed of Changting County, Fujian Province, China, which is a typical representative of the red soil hilly region of China. The results show that: 1) the soil fertility is obviously improved through the four ecological restoration measures, which impels soil fertility catastrophe. Among 89 soil samples, catastrophic soil samples and stable soil samples account for 26(29.21%) and 63(70.79%) of the samples, respectively. The four ecological restoration measures are listed in the order lowquality forest improvement > arbor–bush–herb mixed plantation > orchard improvement > closing measures according to the proportions of catastrophic soil samples. A typical soil sample in Bashilihe that can self-develop is selected as the criterion to judge the upper lobe and lower lobe of soil fertility in the process surface of the Cusp catastrophe model. Twenty-six(29.21%) were in the middle lobe, 10(11.24%) were in the upper lobe, and 53(70.79%) were in the lower lobe. The catastrophic direction of 26 catastrophic soil samples is to the upper lobe according to soil and water loss change as well as fieldwork. There is a significant positive correlation of Δ with soil and water loss change, and the lower soil and water loss relates to higher catastrophic probability. 2) Soil fertility self-development could be regionalized as "Soil fertility can self-develop" whose area was 12.74 km2(28.33%) distributed mainly in the leftmost and rightmost parts, "Soil fertility tends to self-develop" whose area was 11.63 km2(25.89%) distributed mainly in the middle part, and "Soil fertility cannot self-develop" whose area was 20.58 km2(45.78%) distributed mainly between the above two types. 3) There is no need to take ecological restoration measures and excessive human interference should be avoided in the future in regions of "Soil fertility can self-develop" and "Soil fertility tends to self-develop," and ecological restoration measures should be taken in region of "Soil fertility cannot self-develop." 4) We suggest withdrawal and implementation of ecological restoration measures should be incorporated into the evaluation criteria of ecological restoration to avoid misuse of funds. 展开更多
关键词 Soil fertility Catastrophe Ecological restoration Red soil hilly region
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Evaluation of Antitumor,Immunomodulatory and Free Radical Scavenging Effects of A New Herbal Prescription Seaweed Complex Preparation 被引量:3
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作者 LIU Xin SHAO Changlun +2 位作者 KONG Wenwen FANG Yuchun WANG Changyun 《Journal of Ocean University of China》 SCIE CAS 2013年第3期515-520,共6页
Seaweed Complex Preparation (SCP) is a clinical traditional Chinese medicine preparation which is composed of seven traditional Chinese herbs, and it has been used for treatment of lung cancer, liver cancer and dige... Seaweed Complex Preparation (SCP) is a clinical traditional Chinese medicine preparation which is composed of seven traditional Chinese herbs, and it has been used for treatment of lung cancer, liver cancer and digestive cancer. However, little infor- mation is available about the pharmacodynamic basis. The antitumor, immunomodulatory and free radical scavenging effects of SCP were evaluated in this study. Transplanted tumor in vivo method was used to determine the antitumor effect. The effects on spleno- cyte proliferation and phagocytosis of macrophages in tumor-bearing mice were measured by the MTT method and the phagocytizing cock red blood cell (CRBC) method respectively. The scavenging activities of SCP on DPPH and hydroxyl radicals in vitro were investigated. It was found that the medium-dose and high-dose of SCP could significantly inhibit the growth of transplanted hepatic tumor of murine hepatocarcinoma cell line H22, and promote proliferation of splenocytes and phagocytosis of macrophages. SCP possessed noticeable scavenging activities on DPPH and hydroxyl radicals. The antiturnor effects of SCP might be achieved by im- proving immune system and scavenging free radicals, which is in accordance with the viewpoint of traditional Chinese medicine in promoting the body resistance and eliminating pathogenic factors for cancer treatment. 展开更多
关键词 traditional Chinese medicine preparation Seaweed complex preparation ANTITUMOR IMMUNOMODULATORY free radicalscavenging
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Chinese and Western medicine treatment of blocking antibody in recurrent spontaneous abortion
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作者 Ping Shang Feng Xiaoling 《World Journal of Integrated Traditional and Western Medicine》 2016年第4期8-12,共5页
The causes of recurrent spontaneous abortion are complex traditional Chinese medicine holds that its etiology is losses of spleen and kidney qi, qi and xue deficiency, in addition to secretion, genetic, anatomical, in... The causes of recurrent spontaneous abortion are complex traditional Chinese medicine holds that its etiology is losses of spleen and kidney qi, qi and xue deficiency, in addition to secretion, genetic, anatomical, infection, systemic diseases, environmental factors and other related immune factors, the deficiency of blocking antibody is also one of the reasons for the lack of immune factors. In treating it, Chinese medicine treatment combines the patients personal constitution and treatment based on syndrome differentiation; Western medicine treatment mainly applies Aspirin, active immune lymphocyte treatment, low molecular heparin, gamma globulin protein passive immune treatment and psychological intervention therapy. In this paper, a review of the treatment methods for closed antibodies in the past 5 years is made. 展开更多
关键词 Recurrent spontaneous abortion Blocking antibody Treatment based on syndrome differentitation Lymphocyte Immunotherapy Intravenous Immunoglobulin
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The Analysis of Secure HARQ with Chase Combining over Block Fading Channel 被引量:1
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作者 Yue Wu Lukman A Olawoyin +1 位作者 Nana Zhang Hongwen Yang 《China Communications》 SCIE CSCD 2016年第5期82-88,共7页
In this letter, the physical layer security of hybrid automatic repeat request with chase combining(HARQ-CC) scheme is investigated from the viewpoint of information theory. Different from the literature which used Wy... In this letter, the physical layer security of hybrid automatic repeat request with chase combining(HARQ-CC) scheme is investigated from the viewpoint of information theory. Different from the literature which used Wyner code, our analysis focuses on the general scenario without specific code. We firstly obtain the outage probability of both main channel and wiretap channel. Since retransmissions are completely determined by main channel, we then prove that its achievable diversity order equals to maximum transmission number() while this order of wiretap channel is only one. Furthermore, we evaluate the metric of secure gap which demonstrates the difference between main channel and wiretap channel with reliable and secure constraints. As increases, the secure gap decreases monotonously. When is large enough, the security can be guaranteed even if wiretap channel is better than main channel. 展开更多
关键词 physical layer security HARQ chase combining outage probability diversity order secure gap
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龚嘴水电站机组开机过程中调速器参数变化分析研究
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作者 王建平 《水电厂自动化》 2013年第3期62-63,共2页
龚嘴水电站机组调速系统电气控制部分采用武汉能事达公司的三菱PLC进行调节控制,曾经出现过机组开机过程中调速器参数发生变化导致调速器频繁抽动的现象。本文根据现场实际进行了细致分析,提出了切实可行的应对措施和处理办法,有效地杜... 龚嘴水电站机组调速系统电气控制部分采用武汉能事达公司的三菱PLC进行调节控制,曾经出现过机组开机过程中调速器参数发生变化导致调速器频繁抽动的现象。本文根据现场实际进行了细致分析,提出了切实可行的应对措施和处理办法,有效地杜绝了这种现象的发生。希望能对使用类似设备的水电站检修维护人员有所启迪帮助。 展开更多
关键词 伺服电机自复中调速器 三菱PLC 参数变化 原因分析 解决办法
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巨型机组调速器电液伺服系统在官地水电站上的应用 被引量:2
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作者 陈登山 朱祥 张太祥 《水电自动化与大坝监测》 2013年第1期13-16,共4页
本文主要介绍了600MW级水电站巨型机组调速器液压系统的特点及现场应用,从设备概况、主配压阀选型、液压控制系统原理、自复中、液压手动、电手动等方面进行了逐步描述,给出了现场试验波形和数据,并进行了分析。结果表明,该调速系统各... 本文主要介绍了600MW级水电站巨型机组调速器液压系统的特点及现场应用,从设备概况、主配压阀选型、液压控制系统原理、自复中、液压手动、电手动等方面进行了逐步描述,给出了现场试验波形和数据,并进行了分析。结果表明,该调速系统各项性能指标完全满足巨型水轮发电机组的控制要求,可供水电站设计及运行人员参考。 展开更多
关键词 调速器 主配压阀 自复中 电手动
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