|
<p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span lang="EN-US"><font face="Times New Roman">34</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">.无载调压的变压器切换分接头后,测量直流电阻不合格是什么原因?</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">答:切换分接头后,测量三相电阻应平衡。若不平衡其差值不得超过平均值的</span><span lang="EN-US"><font face="Times New Roman">2</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">%,并参考历次测量数据。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">若经过来回多次切换后,三相电阻仍不平衡,可能是由下列原因造成的:</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">1</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)分接头开关接触不良,如触点烧伤、不清洁、电镀层脱落、弹簧压力不够等。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">2</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)分接开关引出导线在运行中开焊,多股导线有部分断股。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">3</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)三角形接线一相断线,此时未断线的两相电阻值为正常值的</span><span lang="EN-US"><font face="Times New Roman">1.5</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">倍,断线相的电阻值为正常值的</span><span lang="EN-US"><font face="Times New Roman">3</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">倍。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span lang="EN-US"><font face="Times New Roman">35.</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">变压器瓦斯保护的使用有哪些规定?</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">答:变压器瓦斯保护的使用规定如下:</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">1</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)变压器投入前重瓦斯保护应作用于跳闸,轻瓦斯保护作用于信号。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">2</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)运行和备用中的变压器,重瓦斯保护应投跳闸,轻瓦斯保护投信号。重瓦斯保护和差动保护不许同时停用。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">3</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)变压器在进行滤油、加油、更换硅胶及处理呼吸器时,应先将重瓦斯保护改投信号,此时变压器的其他保护(如差动、速断保护等)仍应投入跳闸。工作完成,变压器空气排尽后,方可将重瓦斯保护重新投入跳闸。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">4</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)当变压器油位异常升高或油路系统有异常现象时,为查明原因,需要打开各放气或放油塞子、阀门,检查呼吸器或进行其他工作时,必须先将重瓦斯保护改投信号,然后才能开始工作。工作结束后即将重瓦斯保护重新投入跳闸。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">5</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)在地震预报期间,根据变压器的具体情况和气体继电器的类型来确定将重瓦斯保护投入跳闸或信号。地震引起重瓦斯动作停运的变压器,在投运前应对变压器及瓦斯保护进行检查试验,确定无异常后方可投入,</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">6</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)变压器大量漏油致使油位迅速下降,禁止将重瓦斯保护改投信号。</span></p><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt;"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">(</span><span lang="EN-US"><font face="Times New Roman">7</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: "Times New Roman"; mso-hansi-font-family: "Times New Roman";">)变压器轻瓦斯信号动作,若因油中剩余空气逸出或强迫油循环系统吸入空气引起,而且信号动作间隔逐渐缩短,将造成跳闸时,如无备用变压器,则将重瓦斯保护改投信号,同时应立即检查原因加以消除。但如有备用变压器,则应切至备用变压器,而不准使运行中变压器的重瓦斯保护改投信号。</span></p> |
|