20春学期《电机原理与拖动》在线平时作业3

adminhan

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">交流绕组短距系数是不大于<span lang="EN-US">1</span>的数值。（ 　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

&nbsp; <span style="LINE-HEIGHT: 150%; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">电刷轴线两边导体中电流方向相反。（</span><span style="LINE-HEIGHT: 150%; mso-bidi-font-size: 10.5pt"> <span style="mso-spacerun: yes">&nbsp;</span></span><span style="LINE-HEIGHT: 150%; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　）</span><span lang="EN-US" style="LINE-HEIGHT: 150%; mso-bidi-font-size: 10.5pt"><o:p></o:p></span>
A:错误
B:正确

<span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">他励直流电动机接线上与并励电动机相同，主磁极绕组与电枢绕组并联。（</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"><span style="mso-spacerun: yes">&nbsp; </span></span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">）</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"><br style="mso-special-character: line-break" /><br style="mso-special-character: line-break" /></span>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">三相异步电动机以最大转矩起动，临界转差率为<span lang="EN-US">1</span>。（ 　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

<span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-bidi-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">机械特性曲线硬度好，表示电磁转矩有较大变化时，电机转速变化不大。（　）</span>
A:错误
B:正确

<span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">转子旋转磁场转速与同步转速相同。（</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"> </span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">　）</span>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">三相异步电动机额定转速<span lang="EN-US">1470r/min</span>，则同步转速也是<span lang="EN-US">1470r/min</span>。（ 　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="LINE-HEIGHT: 150%; FONT-SIZE: 10.5pt">使用变压器标幺值计算电路参数，要将二次侧参数折算到一次侧。（　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

<span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">一台三相异步电动机，电源频率为</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">50Hz</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">极对数是</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">2</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">这台电动机的旋转磁场转速为</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">3000</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">转</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">/</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">分。（</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"> </span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">　）</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"><br style="mso-special-character: line-break" /><br style="mso-special-character: line-break" /></span>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="LINE-HEIGHT: 150%; FONT-SIZE: 10.5pt">变压器二次侧额定电压是指一次侧加额定电压、二次侧带额定负载时的电压。（　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">异步电动机处于正向回馈状态时，转差率<span lang="EN-US">s&lt;0</span>。（ 　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">交流电机通入交流电，所以电机转速不断变化；直流电机通入直流电，所以电机转速恒定。（　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

<span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">直流电动机主磁极在气隙中建立的磁场称为主磁场。（</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"><span style="mso-spacerun: yes">&nbsp; </span></span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">）</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"><br style="mso-special-character: line-break" /><br style="mso-special-character: line-break" /></span>
A:错误
B:正确

&nbsp; <span style="LINE-HEIGHT: 150%; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">直流电机的电枢绕组是闭合的。（</span><span style="LINE-HEIGHT: 150%; mso-bidi-font-size: 10.5pt"> <span style="mso-spacerun: yes">&nbsp;</span></span><span style="LINE-HEIGHT: 150%; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　）</span><span lang="EN-US" style="LINE-HEIGHT: 150%; mso-bidi-font-size: 10.5pt"><o:p></o:p></span>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">旋转物体转动惯量就是物体的飞轮惯量。（　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

<span style="FONT-FAMILY: 宋体; FONT-SIZE: 10.5pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-ascii-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">在变压器中由交变磁通产生的感应电动势，其正方向与产生该磁通的电流方向相反。（</span><span style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA" lang="EN-US"><span style="mso-spacerun: yes">&nbsp; </span></span><span style="FONT-FAMILY: 宋体; FONT-SIZE: 10.5pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-ascii-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">）</span><span style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA" lang="EN-US"><br style="mso-special-character: line-break" /><br style="mso-special-character: line-break" /></span>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">直流电动机在回馈状态，电机转速一定高于理想空载转速。（　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">定子旋转磁场与转子同步。（　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">三相异步电动机正常运行时，负载转矩增加，转差率增大。（　）<span lang="EN-US"><o:p></o:p></span></span></p>
A:错误
B:正确

&nbsp; <p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">电动机能耗制动比反接制动更消耗电能。（　）<span lang="EN-US" style="COLOR: red"><o:p></o:p></span></span></p>
A:错误
B:正确

<span style="FONT-FAMILY: 宋体; FONT-SIZE: 10.5pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-ascii-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">变压器基本铁耗是铁心中的磁滞损耗。（</span><span style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA" lang="EN-US"><span style="mso-spacerun: yes">&nbsp; </span></span><span style="FONT-FAMILY: 宋体; FONT-SIZE: 10.5pt; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-ascii-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">）</span><span style="FONT-FAMILY: 'Times New Roman'; FONT-SIZE: 10.5pt; mso-fareast-font-family: 宋体; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA" lang="EN-US"><br style="mso-special-character: line-break" /><br style="mso-special-character: line-break" /></span>
A:错误
B:正确

<span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">直流电机作为发电机运行时，电枢电动势</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">E</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">与电枢电流</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">I</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">的方向相反。（</span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"> <span style="mso-spacerun: yes">&nbsp;</span></span><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">　）</span><span lang="EN-US" style="FONT-SIZE: 10.5pt; FONT-FAMILY: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体"><br style="mso-special-character: line-break" /><br style="mso-special-character: line-break" /></span>
A:错误
B:正确

<p><span style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'; mso-font-kerning: 1.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-bidi-font-family: 'Times New Roman'">&nbsp; </span></p><p style="LINE-HEIGHT: 150%"><span style="FONT-SIZE: 10.5pt; LINE-HEIGHT: 150%">绕线式异步电动机转子回路串电阻越大，起动转矩越大，最大转矩也越大。（　）<span lang="EN-US" style="COLOR: red"><o:p></o:p></span></span></p>
A:错误
B:正确

&nbsp; <span style="LINE-HEIGHT: 150%; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">物理中线是电枢表面磁场的分界线。（</span><span style="LINE-HEIGHT: 150%; mso-bidi-font-size: 10.5pt"> <span style="mso-spacerun: yes">&nbsp;</span></span><span style="LINE-HEIGHT: 150%; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　）</span><span lang="EN-US" style="LINE-HEIGHT: 150%; mso-bidi-font-size: 10.5pt"><o:p></o:p></span>
A:错误
B:正确

&nbsp; <span style="LINE-HEIGHT: 150%; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">串励电机流过励磁绕组电流和流过电枢绕组电流相等。（</span><span style="LINE-HEIGHT: 150%; mso-bidi-font-size: 10.5pt"> <span style="mso-spacerun: yes">&nbsp;</span></span><span style="LINE-HEIGHT: 150%; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.5pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　）</span><span lang="EN-US" style="LINE-HEIGHT: 150%; mso-bidi-font-size: 10.5pt"><o:p></o:p></span>
A:错误
B:正确