【判断题】【消耗次数:1】
根据功率分配的不同异步电动机的串级调速分为“机械串级”和“电气串级”两种调速方法。
正确
错误
参考答案:
复制
纠错
相关题目
【单选题】 下列异步电动机调速方法属于转差功率消耗型的调速系统是 ()。
①  降电压调速
②  串级调速
③  变极调速
④  变压变频调速
【单选题】 下列异步电动机调速方法属于转差功率不变型的调速系统是
①  A.降电压调速
②  B.串级调速
③  C.变极调速
④  D.变压变频调速
【判断题】 绕线式转子三相异步电动机在转子中串电阻调速属于恒转矩调速。
①  正确
②  错误
【单选题】 在转子回路串一变阻器调速只适用于绕线式异步电动机。
①  正确
②  错误
【单选题】 异步电动机三种基本调速方法中,不含()。
①  变极调速
②  变频调速
③  变转差率调速
④  变电流调速
【单选题】 以下可对异步电动机进行调速的方法是( )。
①  改变电压的大小
②  改变电动机的供电频率
③  改变电压的相位
④  改变电动机转子绕组匝数
【判断题】 起重机上采用的绕线式异步电动机为了满足起重机调速范围宽,调速平滑的要求,应采用转子串调速电阻?
①  正确
②  错误
【单选题】 下列交流异步电动机的调速方法中,应用最广的是
①  A.降电压调速
②  B.变极对数调速
③  C.变压变频调速
④  D.转子串电阻调速
【单选题】 异步电动机VVVF调速系统的机械特性最好的是()
①  恒压频比控制
②  B恒定子磁通控制
③  C恒气隙磁通控制
④  D恒转子磁通控制
【单选题】 增加绕线式异步电动机起动转矩方法有转子串适当的电阻,转子串频敏变阻器。
①  正确
②  错误
随机题目
【单选题】 _____muchisknownaboutwhatoccursduringsleep,theprecisefunctionofsleepanditsdifferentstagesremainlargelyintherealmofassumption.
①  Because
②  Since
③  For
④  While
【单选题】 Ive never been to Beijing, but its the place _______.
①  where Id like to visit
②  in which Id like to visit
③  I most want to visit
④  that I want to visit it most
【单选题】 A survey was carried out on the death rate of new born babies in that region,________were surprising.
①  as results
②  which results
③  the results of it
④  the results of which
【单选题】 The hours _______ the children spend in their one-way relationship with television people undoubtedly affect their relationships with real-life people.
①  in which
②  on which
③  when
④  that
【单选题】 New York is famous for its skyscrapers,_______has more than 100 storeys.
①  the highest
②  the highest of that
③  the highest of which
④  the highest of them
【单选题】 InIndiamorethanonehundredlanguagesarespoken,______whichonlyfourteenarerecognizedasofficial.
①  of
②  in
③  with
④  within
【单选题】 AlthoughAnneishappywithhersuccess,shewonders_____willhappentoherprivatelife.
①  that
②  what
③  it
④  this
【单选题】 ______ you are leaving tomorrow, we can eat dinner together tonight.
①  For
②  Since
③  Before
④  While
【单选题】 The residents, _____had been damaged by the fire, were given help by the Red Cross.
①  all of their homes
②  all their homes
③  whose all homes
④  all of whose homes
【单选题】 If motorists do not observe the traffic regulations, they will be stopped, ticked, and _______.
①  have to pay a fine
②  to pay a fine
③  fined
④  fired