600MW機(jī)組D600E汽輪機(jī)調(diào)門開度的問題

600MW機(jī)組D600E汽輪機(jī)調(diào)門開度的問題我公司采用東方汽輪機(jī)廠引進(jìn)技術(shù)生產(chǎn)的超臨界、一次中間再熱、沖動(dòng)式、單軸、三缸四排汽、雙背壓、純凝汽式汽輪機(jī)，汽輪機(jī)型號(hào)：N600-24.2/566/566型，額定出力600MW，最大連續(xù)出力634.185MW。機(jī)組采用復(fù)合變壓運(yùn)行方式。主蒸汽通過上、下對(duì)稱布置的4個(gè)進(jìn)汽口進(jìn)入汽輪機(jī)，通過高壓8級(jí)作功后去鍋爐再熱器。再熱蒸汽經(jīng)過中壓聯(lián)合汽閥進(jìn)入汽輪機(jī)的中壓部分作功，作功后的蒸汽，經(jīng)一根異徑連通管分別進(jìn)入兩個(gè)低壓缸，作功后的乏汽排入兩個(gè)不同背壓的凝汽器。高壓缸共有8級(jí)，中壓缸共有6級(jí)，低壓缸共有4×7級(jí)，全機(jī)共有42級(jí)。額定工況下，汽輪機(jī)的效率分別是：高壓缸：86.41%，中壓缸：92.55％，低壓缸：92.97％，汽輪機(jī)效率為92.04％。汽輪發(fā)電機(jī)組軸系中除1號(hào)、2軸承采用可傾瓦式軸承外，其余均采用橢圓形軸承。高壓內(nèi)缸噴嘴室由四組噴嘴組成，沿圓周方向布置，四根高壓進(jìn)汽導(dǎo)管為上下垂直布置，進(jìn)汽管直接插入高壓內(nèi)缸的噴嘴室。從機(jī)頭向發(fā)電機(jī)方向看，逆時(shí)針從左上角起依次對(duì)應(yīng)CV1、CV2、CV4、CV3。如圖所示：各噴嘴組及導(dǎo)葉對(duì)應(yīng)關(guān)系如下：噴嘴組導(dǎo)葉數(shù)總面積（平方mm）1589260.82345428.73345428.74589260.8汽輪機(jī)各工況下的主要設(shè)計(jì)參數(shù)如下：項(xiàng)目單位TRL工況T-MCR工況VWO工況THA工況功率MW600634.185660.427600熱耗率kJ/kWh7826749974927512主蒸汽壓力MPa（a）24.224.224.224.2再熱蒸汽壓力MPa（a）4.2114.2464.4393.999主蒸汽溫度℃566566566566再熱蒸汽溫度℃566566566566主蒸汽流量kg/h1814050181405019050001699000再熱蒸汽流量kg/h1480656148975815592361401224高壓缸排汽壓力MPa（a）4.6794.7184.9334.444低壓缸排汽壓力kPa（a）11.84.94.94.9低壓缸排汽流量kg/h102875310285561070305974176補(bǔ)給水率%3000手動(dòng)參考（即調(diào)門總指令）與各調(diào)門開度對(duì)應(yīng)關(guān)系如下（原設(shè)計(jì)值）：cv1cv2cv3cv4icv手動(dòng)參考cv1開度手動(dòng)參考cv2開度手動(dòng)參考cv3開度手動(dòng)參考cv4開度手動(dòng)參考icv開度17.5-317.63-317.6-318.5-3-2.75-519-319-1.8219-2.0619-300200200200200414.4213.43211.82212.06213.43819.19227.45224.23224.75227.451628.79248.51248.16249.14248.512076.78279.05278.51279.59279.092295289.54309.323010.59289.54241003613.13610.943612.623613.11001004617.414513.374515.664617.625614.985618.255621.795322.8256.114.9856.118.2556.121.7953.122.8264156823.626828.666027.8774157226.17231.246934.484157628.627634.167640.3987158031.798037.92804590158233.958240.478247.9690158436.728443.88451.9791158641.88648.848554.749326.168852.588861.598874.149638.559610094100921009743.4910010096105941059849.8110071.47橫軸：手動(dòng)參考縱軸：調(diào)門開度2008年5月，為解決#2軸承震動(dòng)問題，河南電力試驗(yàn)研究院汽機(jī)室建議，將CV1與CV3的閥門曲線進(jìn)行了對(duì)調(diào)，由上圖噴嘴組與導(dǎo)葉對(duì)應(yīng)關(guān)系可知，CV1與CV3對(duì)應(yīng)的噴嘴及導(dǎo)流面積有較大差異，原設(shè)計(jì)中CV1總體開度較小，其閥門曲線與CV3對(duì)調(diào)后開度變大，相應(yīng)的CV3開度變小，由于CV1對(duì)應(yīng)的噴嘴個(gè)數(shù)要遠(yuǎn)大于CV3，即手動(dòng)參考（閥門總指令）在50%--95%之間某一特定值時(shí)，閥門曲線修改后的蒸汽流量要大于原設(shè)計(jì)值的蒸汽流量，一定的負(fù)荷對(duì)應(yīng)一定的蒸汽流量，要保持原蒸汽流量，則必將使手動(dòng)參考（閥門總指令）變小，經(jīng)觀察，在一定的負(fù)荷下，閥門曲線修改后的手動(dòng)參考（閥門總指令）比原設(shè)計(jì)值偏小2%--3%，相應(yīng)得各個(gè)調(diào)門的開度也要變小，節(jié)流損失進(jìn)一步加大。調(diào)門曲線修改前典型工況下各參數(shù)如下（以#1機(jī)為例）：日期3-123-133-123-143-193-143-23負(fù)荷(MW)323350400450500550606手動(dòng)參考82818384838693主汽溫度(℃)563.49570.88563.45565.13564.57561.27566.3主汽壓力(MPa)14.7716.218.0720.3422.3223.924.25高壓調(diào)節(jié)閥前壓力(MPa)14.581617.8520.0822.0623.5723.89CV1開度8.478.738.468.178.413.1120.13CV1高壓調(diào)節(jié)閥后蒸汽壓力(MPa)8.238.8410.1211.6512.6114.216.5CV2開度34.4933.1634.6336.3234.9841.2784.16CV2高壓調(diào)節(jié)閥后蒸汽壓力(MPa)12.8413.7615.7518.1519.5922.1423.6CV3開度41.1339.2641.4343.3141.7449.3495.71CV3高壓調(diào)節(jié)閥后蒸汽壓力(MPa)13.3814.4316.4118.7620.422.5923.64CV4開度48.9946.749.2851.2749.2961.6699.48CV4高壓調(diào)節(jié)閥后蒸汽壓力(MPa)12.2813.1715.0717.318.7221.0422.35調(diào)節(jié)級(jí)壓力9.249.9111.3413.114.1415.9717.57高壓缸左排汽壓力(MPa)2.362.562.923.43.684.154.52高壓缸左排汽溫度(℃)324.93330.27321.19321.38318.7315.87325.7高壓缸右排汽壓力(MPa)2.372.572.923.413.694.164.53高壓缸右排汽溫度(℃)327.58332.9323.61323.64320.89317.87328.12鍋爐主給水流量(T/H)992.871079.011216.331407.421528.21733.931887.97高壓缸排汽母管壓力(MPa)2.322.532.883.363.644.114.48調(diào)門曲線修改后典型工況下各參數(shù)如下（以#1機(jī)為例）：日期11-111-411-511-511-511-311-1負(fù)荷(MW)302350400455504552602手動(dòng)參考80808181818389主汽溫度(℃)563.1565.11562.06565.22563.61560.01564.72主汽壓力(MPa)13.9415.9418.1220.4522.624.0724.11高壓調(diào)節(jié)閥前壓力(MPa)13.7815.7817.9420.2522.3723.8123.8CV1開度38.8537.6638.8839.1839.4541.3765.42CV1高壓調(diào)節(jié)閥后蒸汽壓力(MPa)10.9312.2114.1916.1818.0619.9222.8CV2開度32.531.6532.5932.9133.0834.6456.09CV2高壓調(diào)節(jié)閥后蒸汽壓力(MPa)11.7713.2215.2917.3219.4521.1923.32CV3開度14.8714.8614.8614.8814.8614.8714.87CV3高壓調(diào)節(jié)閥后蒸汽壓力(MPa)8.429.521112.5114.0415.3717.05CV4開度46.0544.9146.3446.5446.8349.0978.09CV4高壓調(diào)節(jié)閥后蒸汽壓力(MPa)10.8812.1414.1316.0318.0219.822.41調(diào)節(jié)級(jí)壓力8.851011.5613.1214.7116.1117.81高壓缸左排汽壓力(MPa)2.242.583.053.433.834.24.6高壓缸左排汽溫度(℃)331.95331.71329.37327.23323.44319.96327.72高壓缸右排汽壓力(MPa)2.252.593.063.453.854.214.62高壓缸右排汽溫度(℃)332.77333.08330.97328.82325.06321.66328.3鍋爐主給水流量(T/H)913.491055.791215.8613831559.721748.891900.15高壓缸排汽母管壓力(MPa)2.212.543.013.393.794.164.56為解決調(diào)門節(jié)流損失問題，建議如下：修改負(fù)荷-壓力對(duì)應(yīng)的曲線，可參考哈爾濱汽輪機(jī)的壓力曲線，在30%--100%負(fù)荷之間時(shí)，滑壓運(yùn)行（原設(shè)計(jì)30%--90%負(fù)荷之間時(shí)，滑壓運(yùn)行，90%--100%負(fù)荷之間時(shí)，定壓運(yùn)行）。這樣修改后，相當(dāng)于在30%--100%負(fù)荷之間時(shí)，降低了主汽壓，可以使調(diào)門開大，減小節(jié)流損失，但降低初參數(shù)，會(huì)使整個(gè)熱力循環(huán)的效率降低，孰優(yōu)孰劣，仍需論證。修改閥門曲線，使手動(dòng)參考（閥門總指令）在70%--100%之間時(shí)，使CV1與CV4保持或接近全開，利用CV