< class=MsoNormal><SPAN>1.</SPAN><SPAN>什么是</SPAN><SPAN>DEH</SPAN><SPAN>？为什么要采用</SPAN><SPAN>DEH</SPAN><SPAN>控制？</SPAN><SPAN><BR></SPAN><SPAN>所谓</SPAN><SPAN>DEH</SPAN><SPAN>就是汽轮机数字式电液控制系统,由计算机控制部分和</SPAN><SPAN>EH</SPAN><SPAN>液压执行机构组成。采用</SPAN><SPAN>DEH</SPAN><SPAN>控制可以提高高、中压调门的控制精度,为实现</SPAN><SPAN>CCS</SPAN><SPAN>协调控制及提高整个机组的控制水平提供了基本保障,更有利于汽轮机的运行。</SPAN><SPAN><BR>2.DEH</SPAN><SPAN>系统有哪些主要功能？</SPAN><SPAN><BR></SPAN><SPAN>汽轮机转数控制;自动同期控制;负荷控制;参与一次调頻;机、炉协调控制;快速减负荷;主汽压控制;单阀、多阀控制;阀门试验;轮机程控启动;</SPAN><SPAN>OPC</SPAN><SPAN>控制;甩负荷及失磁工况控制;双机容错;与</SPAN><SPAN>DCS</SPAN><SPAN>系统实现数据共享;手动控制。</SPAN><SPAN><BR>3.DEH</SPAN><SPAN>系统仿真器有何作用？</SPAN><SPAN><BR>DEH</SPAN><SPAN>仿真器可以在实际机组不启动的情况下,用仿真器与控制机相连,形成闭环系统,可以对系统进行闭环,静态和动态调试,包括整定系统参数,检查各控制功能,进行模拟操作培训操作人员等。</SPAN><SPAN> <BR>4.EH</SPAN><SPAN>系统为什么采用高压抗燃油做为工质？</SPAN><SPAN><BR></SPAN><SPAN>随着汽轮机机组容量的不断增大,蒸汽参数不断提高,控制系统为了提高动态响应而采用高压控制油,在这种情况下,电厂为防止火灾而不能采用传统的透平油作为控制系统的介质。所以</SPAN><SPAN>EH</SPAN><SPAN>系统设计的液压油为磷酸酯型高压抗燃油。</SPAN><SPAN><?xml:namespace prefix = o ns = "urn:schemas-microsoft-com fficeffice" /><o:p></o:p></SPAN></P>
< class=MsoNormal><SPAN>5.DEH</SPAN><SPAN>系统由哪几部分组成？</SPAN><SPAN><BR>1</SPAN><SPAN>）</SPAN><SPAN>01</SPAN><SPAN>柜</SPAN><SPAN>—</SPAN><SPAN>基本控制计算机柜,完成对汽轮机的基本控制功能,即转速控制、负荷控制及超速保护功能;</SPAN><SPAN><BR>2</SPAN><SPAN>）</SPAN><SPAN>02</SPAN><SPAN>柜</SPAN><SPAN>—</SPAN><SPAN>基本控制端子柜,在控制实际汽轮机时,信号连到实际设备,进行仿真超作时,信号连到仿真器;</SPAN><SPAN><BR>3</SPAN><SPAN>）手动操作盘,当一对</SPAN><SPAN>DPU</SPAN><SPAN>均故障时或操作员站故障时,对</SPAN><SPAN>DEH</SPAN><SPAN>进行手动操作;</SPAN><SPAN><BR>4</SPAN><SPAN>）</SPAN><SPAN>EH</SPAN><SPAN>油液压部分。</SPAN><SPAN><BR>6.DEH</SPAN><SPAN>系统技术性能指标都有哪些？</SPAN><SPAN><BR>1</SPAN><SPAN>）控制范围</SPAN><SPAN>0</SPAN><SPAN>～</SPAN><SPAN>3600r/min</SPAN><SPAN>,精度</SPAN><SPAN>±1r/min</SPAN><SPAN>;</SPAN><SPAN><BR>2</SPAN><SPAN>）负荷控制范围</SPAN><SPAN>0</SPAN><SPAN>～</SPAN><SPAN>115%</SPAN><SPAN>,负荷控制精度</SPAN><SPAN>0.5%</SPAN><SPAN>;</SPAN><SPAN><BR>3</SPAN><SPAN>）转速不等率</SPAN><SPAN>3</SPAN><SPAN>～</SPAN><SPAN>6%</SPAN><SPAN>可调;</SPAN><SPAN><BR>4</SPAN><SPAN>）抽汽压力控制精度</SPAN><SPAN>1%</SPAN><SPAN>;</SPAN><SPAN><BR>5</SPAN><SPAN>）系统迟缓率,调速系统</SPAN><SPAN><0.06%</SPAN><SPAN>;</SPAN><SPAN><BR>6</SPAN><SPAN>）甩满负荷下转速超调量小于额定转速的</SPAN><SPAN>7%</SPAN><SPAN>,维持</SPAN><SPAN>3000r/min</SPAN><SPAN>;</SPAN><SPAN><BR>7</SPAN><SPAN>）平均无故障工作时间</SPAN><SPAN>MTBF>25000</SPAN><SPAN>小时;</SPAN><SPAN><BR>8</SPAN><SPAN>）系统可用率不小于</SPAN><SPAN>99.9%</SPAN><SPAN>;</SPAN><SPAN><BR>9</SPAN><SPAN>）</SPAN><SPAN>DEH</SPAN><SPAN>控制装置运行环境</SPAN><SPAN>0</SPAN><SPAN>～</SPAN><SPAN>40</SPAN><SPAN>℃</SPAN><SPAN>,相对湿度</SPAN><SPAN>10</SPAN><SPAN>～</SPAN><SPAN>95%</SPAN><SPAN>（不结露）;</SPAN><SPAN><BR>10</SPAN><SPAN>）电源负荷率</SPAN><SPAN>50%</SPAN><SPAN>,双电源。柜内供电装置</SPAN><SPAN>1</SPAN><SPAN>：</SPAN><SPAN>1</SPAN><SPAN>冗余,交流双路供电;</SPAN><SPAN><BR>11</SPAN><SPAN>）系统应能承受距离设备</SPAN><SPAN>1.2</SPAN><SPAN>米</SPAN><SPAN>,</SPAN><SPAN>频率高达</SPAN><SPAN>470MHz</SPAN><SPAN>,输出功率</SPAN><SPAN>5</SPAN><SPAN>瓦的电磁和射频干扰;</SPAN><SPAN><BR>12</SPAN><SPAN>）机柜内每种类型</SPAN><SPAN>I/0</SPAN><SPAN>模件都应有</SPAN><SPAN>10%</SPAN><SPAN>的备用量,每个机柜都应有</SPAN><SPAN>10%</SPAN><SPAN>的模件插槽备用量,</SPAN><SPAN>DPU</SPAN><SPAN>处理器负荷率</SPAN><SPAN><30%</SPAN><SPAN>,存储器负荷率</SPAN><SPAN><40%</SPAN><SPAN>;</SPAN><SPAN><BR>13</SPAN><SPAN>）</SPAN><SPAN>DPU</SPAN><SPAN>按</SPAN><SPAN>1</SPAN><SPAN>：</SPAN><SPAN>1</SPAN><SPAN>冗余配置,当主</SPAN><SPAN>DPU</SPAN><SPAN>故障时,应能自动无扰切换至备用</SPAN><SPAN>DPU</SPAN><SPAN>。</SPAN><SPAN><o:p></o:p></SPAN></P>
< class=MsoNormal><SPAN>7.OPC</SPAN><SPAN>、</SPAN><SPAN>AST</SPAN><SPAN>都代表什么意思？</SPAN><SPAN><BR>OPC</SPAN><SPAN>代表机组超速保护系统;</SPAN><SPAN><BR>AST</SPAN><SPAN>代表自动停机危急遮断控制系统。</SPAN><SPAN><BR>8.TV</SPAN><SPAN>、</SPAN><SPAN>GV</SPAN><SPAN>、</SPAN><SPAN>RV</SPAN><SPAN>、</SPAN><SPAN>IV</SPAN><SPAN>各代表什么？</SPAN><SPAN><BR>TV</SPAN><SPAN>代表高压主汽门控制回路;</SPAN><SPAN> GV</SPAN><SPAN>代表高压调门控制回路;</SPAN><SPAN><BR>RV</SPAN><SPAN>代表中压主汽门控制回路;</SPAN><SPAN>IV</SPAN><SPAN>代表中压调门控制回路。</SPAN><SPAN><BR>9.HP</SPAN><SPAN>、</SPAN><SPAN>DP</SPAN><SPAN>、</SPAN><SPAN>DV</SPAN><SPAN>都代表什么意思？</SPAN><SPAN><BR>HP</SPAN><SPAN>代表</SPAN><SPAN>EH</SPAN><SPAN>系统压力油管路;</SPAN><SPAN>DP</SPAN><SPAN>代表</SPAN><SPAN>EH</SPAN><SPAN>系统有压回油管路;</SPAN><SPAN><BR>DV</SPAN><SPAN>代表</SPAN><SPAN>EH</SPAN><SPAN>系统无压回油管路。</SPAN><SPAN><BR>10.</SPAN><SPAN>什么是</SPAN><SPAN>TPC</SPAN><SPAN>控制？</SPAN><SPAN><BR>TPC</SPAN><SPAN>控制即主蒸汽压力控制,是指运行人员能投切软件</SPAN><SPAN>TPC</SPAN><SPAN>控制主蒸汽压力大于某一给定值。可分为</SPAN><SPAN>“</SPAN><SPAN>操作员</SPAN><SPAN>TPC”</SPAN><SPAN>、</SPAN><SPAN>“</SPAN><SPAN>固定</SPAN><SPAN>TPC”</SPAN><SPAN>、遥控</SPAN><SPAN>TPC”</SPAN><SPAN>三种。</SPAN><SPAN><o:p></o:p></SPAN></P>
<P class=MsoNormal><SPAN>11.EH</SPAN><SPAN>油系统由几部分组成？</SPAN><SPAN><BR>EH</SPAN><SPAN>油系统包括供油系统、执行机构和危急遮断系统,供油系统的功能是提供高压抗燃油,并由它来驱动伺服执行机构;执行机构响应从</SPAN><SPAN>DEH</SPAN><SPAN>送来的电指令信号,以调节汽轮机各蒸汽阀开度;危急遮断系统由汽轮机的遮断参数控制,当这些参数超过其运行限制值时该系统就关闭全部汽轮机进汽门或只关闭调速汽门。</SPAN><SPAN><BR>12.EH</SPAN><SPAN>油系统有几个蓄能器？作用分别是什么？</SPAN><SPAN><BR>EH</SPAN><SPAN>油系统</SPAN><SPAN>==</SPAN><SPAN>有</SPAN><SPAN>5</SPAN><SPAN>个蓄能器,一个在油箱旁边,吸收</SPAN><SPAN>EH</SPAN><SPAN>油泵出口压力的高频脉动分量,维持系统油压平稳;其余</SPAN><SPAN>4</SPAN><SPAN>个分两组,分别位于左右两侧高压调门旁边,当系统瞬间用油量很大时,参与向系统供油,保证系统油压稳定。</SPAN><SPAN><BR>13.</SPAN><SPAN>蓄能器中气囊的氮气压力是如何规定的？</SPAN><SPAN><BR></SPAN><SPAN>正常运行中蓄能器中气囊的氮气压力应保持在</SPAN><SPAN>8.8</SPAN><SPAN>～</SPAN><SPAN>9.2MPa</SPAN><SPAN>,压力小于</SPAN><SPAN>8.0MPa</SPAN><SPAN>时应进行充氮气。</SPAN><SPAN><BR>14.AST</SPAN><SPAN>电磁阀有何作用？</SPAN><SPAN><BR></SPAN><SPAN>正常运行中,</SPAN><SPAN>AST</SPAN><SPAN>电磁阀被通电励磁关闭,从而封闭了</SPAN><SPAN>AST</SPAN><SPAN>母管上的泄油通路,使所有执行机构活塞下腔的油压能够建立起来;当电磁阀失电打开,则</SPAN><SPAN>AST</SPAN><SPAN>母管泄油,导致所有汽门关闭而使汽轮机停机。</SPAN><SPAN><BR>15.</SPAN><SPAN>隔膜阀的作用及其工作原理是什么？</SPAN><SPAN><BR></SPAN><SPAN>隔膜阀联接着润滑油的低压安全油系统与</SPAN><SPAN>EH</SPAN><SPAN>油的高压安全油系统,其作用是润滑油系统的低压安全油压力降低到</SPAN><SPAN>1.4Mpa</SPAN><SPAN>时,可以通过</SPAN><SPAN>EH</SPAN><SPAN>油系统</SPAN><SPAN><o:p></o:p></SPAN></P>
<P class=MsoNormal><SPAN>当汽轮机正常工作时,润滑系统的透平油通入阀内活塞上的油室中,克服弹簧力,使阀在关闭位置,堵住</SPAN><SPAN>EH</SPAN><SPAN>危急遮断油母管的泄油通道,使</SPAN><SPAN>EH</SPAN><SPAN>系统投入工作。当危急遮断器动作或手动打闸时均能使透平油压力降低或消失,从而使压缩弹簧打开把</SPAN><SPAN>EH</SPAN><SPAN>危急遮断油泄掉,关闭所有进汽门。</SPAN><SPAN><BR>16.</SPAN><SPAN>位移传感器（</SPAN><SPAN>LVDT</SPAN><SPAN>）有几个？作用是什么？</SPAN><SPAN><BR></SPAN><SPAN>为了提高控制系统的可靠性,每个执行机构中安装两只位移传感器,共</SPAN><SPAN>16</SPAN><SPAN>只。作用是利用差动变压器原理,将油动机活塞的位移转换为</SPAN><SPAN>LVDT</SPAN><SPAN>中铁芯与线圈间相对位移的电信号输出,作为伺服放大器的负反馈信号。</SPAN><SPAN><BR>17.</SPAN><SPAN>再生装置有什么作用？由几个滤器组成？</SPAN><SPAN><BR></SPAN><SPAN>再生装置是用来存储吸附剂和使抗燃油得到再生（使油保持中性、去除水份等）的装置。该装置主要由硅藻土滤器和精密滤器（波纹纤维滤器）等组成。</SPAN><SPAN><BR>EH</SPAN><SPAN>油系统中的水分,会使磷酸脂抗燃油水解,并给油质的再生处理带来困难,同时其水解产物对磷酸脂的水解过程又是极强的催化剂。因此,必须在运行中用油再生系统来控制抗燃油的酸值,防止系统中酸性分解物的增加。</SPAN><SPAN><BR>18.</SPAN><SPAN>油动机快速关闭时,能否将阀芯及阀座损坏？为什么？</SPAN><SPAN><BR></SPAN><SPAN>在油动机快速关闭时,不会将阀芯及阀座损坏。因为在油动机活塞的尾部采用了液压缓冲装置,可以将动能累积的主要部分在冲击发生前、动作的最后瞬间转变为流体的能量,从而保证了阀芯及阀座的冲击应力在允许范围内。</SPAN><SPAN><BR>19.</SPAN><SPAN>卸荷阀有什么作用？</SPAN><SPAN><BR></SPAN><SPAN>当</SPAN><SPAN>EH</SPAN><SPAN>油系统危急遮断油被泄掉时,卸荷阀活塞上油压消失,油动机活塞下腔的</SPAN><SPAN>EH</SPAN><SPAN>压力油克服卸荷阀的弹簧力,通过卸荷阀迅速排到压力回油管,使该卸荷阀对应的执行机构迅速关闭。</SPAN><SPAN><o:p></o:p></SPAN></P>
<P class=MsoNormal><SPAN>20.</SPAN><SPAN>负荷降预测功能的作用是什么？</SPAN><SPAN><BR></SPAN><SPAN>在机组带负荷</SPAN><SPAN>30%</SPAN><SPAN>以上时,一旦发生甩负荷现象,在发生甩负荷的瞬间,机组转速还没上升到保护动作转速之前,</SPAN><SPAN>DEH</SPAN><SPAN>通过油开关和调节级压力判断提前关闭高、中压调门,起到超速保护的作用。并在延时</SPAN><SPAN>3</SPAN><SPAN>～</SPAN><SPAN>4</SPAN><SPAN>秒后,再自动将高、中压调节阀重新开启,维持汽机在同步转速下空转,保证汽机能迅速重新并网。</SPAN><SPAN><BR>21.</SPAN><SPAN>什么是</SPAN><SPAN>RB</SPAN><SPAN>（</SPAN><SPAN>Runback</SPAN><SPAN>）功能？</SPAN><SPAN><BR>RB</SPAN><SPAN>功能就是在发电机失磁时,</SPAN><SPAN>DEH</SPAN><SPAN>系统将自动按每秒钟</SPAN><SPAN>1MW</SPAN><SPAN>的数率减少机组的负荷。</SPAN><SPAN><BR>22.</SPAN><SPAN>机组的各项跳机保护作用在什么设备上？</SPAN><SPAN><BR></SPAN><SPAN>机组的保护如振动、串轴、低油压、低真空、</SPAN><SPAN>110%</SPAN><SPAN>超速等保护均作用于</SPAN><SPAN>AST</SPAN><SPAN>电磁阀上;另外</SPAN><SPAN>103%</SPAN><SPAN>超速保护作用于</SPAN><SPAN>OPC</SPAN><SPAN>电磁阀上。</SPAN><SPAN><BR>23.</SPAN><SPAN>简述伺服控制回路的工作原理。</SPAN><SPAN><BR>DEH</SPAN><SPAN>输出信号首先经函数变换（凸轮特性）到</SPAN><SPAN>VCC</SPAN><SPAN>卡,转换为阀位指令,经功率放大器输出去控制伺服阀、油动机。油动机位移经</SPAN><SPAN>LVDT</SPAN><SPAN>变送器转换为电压信号反馈到综合放大器与阀位指令相比较,当其二者相等时,油动机稳定在某一位置上。</SPAN><SPAN><BR>24.</SPAN><SPAN>超速保护试验装置是由哪几部分组成的？</SPAN><SPAN><BR></SPAN><SPAN>超速保护试验装置由超速保护钥匙和</SPAN><SPAN>“103%”</SPAN><SPAN>、</SPAN><SPAN>“110%”</SPAN><SPAN>、危急遮断三只按钮组成。</SPAN><SPAN><BR>25.OPC</SPAN><SPAN>电磁阀什么作用？</SPAN><SPAN><BR>OPC</SPAN><SPAN>电磁阀是超速保护控制电磁阀,当机组转速达</SPAN><SPAN>103%</SPAN><SPAN>额定转速时,该电磁阀被通电打开,使</SPAN><SPAN>OPC</SPAN><SPAN>母管泄油。相应执行机构上的卸荷阀就快速开启,使调节汽阀迅速关闭。</SPAN></P> |
发表于 2007-3-6 15:04:20
发表于 2007-5-22 07:40:16
