Method of manufacturing a casting nozzle brick
    1.
    发明授权
    Method of manufacturing a casting nozzle brick 失效
    铸造喷嘴砖的制造方法

    公开(公告)号:US4564493A

    公开(公告)日:1986-01-14

    申请号:US602097

    申请日:1984-04-20

    CPC分类号: C04B35/101 B22D41/52 B28B1/24

    摘要: A composition of flake graphite, binder clay and a refractory material is extruded from an auger machine into a mold to form a cylindrical graphitic casting nozzle brick. The mold includes a coaxial core terminating short of an extrusion die of the auger machine, so that the graphitic casting nozzle brick as extruded has a longitudinal bore with one end closed, with transverse holes being subsequently defined through the nozzle brick across the bore adjacent to the closed end. As an alternative, a coaxial core may be connected to an extrusion screw of the auger machine to define an axial through bore in the casting nozzle brick as the latter is extruded.

    摘要翻译: 将片状石墨,粘结剂粘土和耐火材料的组合物从螺旋钻机挤出到模具中以形成圆柱形石墨铸造喷嘴砖。 该模具包括一个终止于螺旋钻机的挤出模头的同轴芯,使得挤出的石墨铸造喷嘴砖具有纵向孔,其一端封闭,随后通过喷嘴砖将横向孔定义成穿过相邻的孔 封闭的一面。 作为替代方案,同轴芯可以连接到螺旋钻机的挤压螺杆,以在铸造喷嘴砖中限定出轴向通孔,因为后者被挤出。

    Field overvoltage protecting apparatus for synchronous machine
    3.
    发明授权
    Field overvoltage protecting apparatus for synchronous machine 失效
    同步电机现场过电压保护装置

    公开(公告)号:US4118749A

    公开(公告)日:1978-10-03

    申请号:US782745

    申请日:1977-03-30

    IPC分类号: H02P9/30 H02H7/08 H02H7/09

    CPC分类号: H02H7/0805

    摘要: An apparatus for protecting a synchronous machine from a field overvoltage is disclosed. The apparatus comprises a field excitation control circuit which is impressed with the armature voltage of the synchronous machine so as to provide a DC power supply for producing a DC output to excite the field winding of the synchronous machine, a first discharge circuit which is adapted to discharge the stored energy of the field winding when the synchronous machine is to be tripped under predetermined conditions, and a second discharge circuit for reducing the field voltage by allowing a field current to flow therethrough in response to generation of an overvoltage whose absolute value is higher than a predetermined level, across the field winding. The resistance of the second discharge circuit is selected to be higher than that of the first discharge circuit so that even in the presence of an overvoltage across the field winding, the overvoltage is suppressed by the second discharge circuit thereby to prevent frequent tripping of the synchronous machine due to overvoltage.

    摘要翻译: 公开了一种用于保护同步电机免受场过电压的装置。 该装置包括励磁励磁控制电路,其被同步电机的电枢电压施加,以便提供用于产生用于激励同步电机的励磁绕组的DC输出的DC电源;第一放电电路, 当同步电机在预定条件下跳闸时,放电励磁绕组的存储能量;以及第二放电电路,用于通过允许场电流响应于其绝对值较高的过电压的产生而流过其中来减小励磁电压 超过预定水平,跨过场绕组。 第二放电电路的电阻被选择为高于第一放电电路的电阻,使得即使在场绕组上存在过电压的情况下,也可以通过第二放电电路抑制过电压,从而防止频率跳闸 机器由于过电压。

    Excitation control apparatus suited for normal stop operation of
synchronous generators
    4.
    发明授权
    Excitation control apparatus suited for normal stop operation of synchronous generators 失效
    励磁控制装置适用于同步发电机的正常停机运行

    公开(公告)号:US4129818A

    公开(公告)日:1978-12-12

    申请号:US806862

    申请日:1977-06-15

    IPC分类号: H02P9/08 H02P3/06

    CPC分类号: H02P9/08

    摘要: Disclosed is an apparatus for carrying out normal stop of a synchronous generator in an advantageous manner without use of a field breaker. The apparatus comprises a six-phase thyristor converter for controlling field excitation of the synchronous generator in dependence upon terminal voltage thereof, which converter exhibits not only a forward conversion function (power rectifier) but also backward conversion function (power inverter). When a generator operation stop command is produced, the operation of the converter in power rectifier mode is changed over to power inverter mode. During the inverter mode operation, when the terminal voltage of the synchronous generator becomes lower than a preset value, a pair of counter part thyristors among the thyristors constituting the converter are simultaneously fired to bring about a short-circuited state in the excitation circuit with all the firing pulses supplied to the other thyristors being suppressed, thereby to complete the stopping operation for the synchronous generator.

    摘要翻译: 公开了一种用于在不使用断路器的情况下以有利的方式执行同步发电机的正常停止的装置。 该装置包括用于根据其端电压来控制同步发电机的场激励的六相晶闸管转换器,该转换器不仅显示正向转换功能(功率整流器)而且还具有反向转换功能(功率逆变器)。 当产生发电机运行停止指令时,将功率整流模式下的转换器的动作转换为电力逆变器模式。 在逆变器模式操作期间,当同步发电机的端子电压变得低于预设值时,构成转换器的晶闸管之间的一对对置部分晶闸管被同时点火,以在所有激励电路中产生短路状态 供给到其他晶闸管的点火脉冲被抑制,从而完成同步发电机的停止动作。

    Field excitation control system for the synchronous generator
    5.
    发明授权
    Field excitation control system for the synchronous generator 失效
    同步发电机励磁励磁控制系统

    公开(公告)号:US3936722A

    公开(公告)日:1976-02-03

    申请号:US457506

    申请日:1974-04-03

    IPC分类号: H02P9/14 H02J3/18 H02P9/10

    摘要: The field excitation flux of the synchronous generator is controlled in response to the summing rotor angle signal of a predetermined set signal and of a rotor angle signal representing a phase difference between the voltage equivalent to an infinite bus voltage and the output voltage from the pilot generator provided on the same rotating shaft as the synchronous generator.

    摘要翻译: 响应于预定设定信号的与转子角度信号相加的转子角度信号和表示无限总线电压等效电压与来自引导发生器的输出电压之间的相位差的转子角度信号来控制同步发电机的励磁通量 设置在与同步发电机相同的旋转轴上。

    Excitation control apparatus for a generator
    6.
    发明授权
    Excitation control apparatus for a generator 失效
    发电机励磁控制装置

    公开(公告)号:US4245182A

    公开(公告)日:1981-01-13

    申请号:US891001

    申请日:1978-03-28

    摘要: A field control apparatus for a generator having a field winding comprises a terminal voltage control unit for controlling a field current of the generator in accordance with a difference between a terminal voltage signal of the generator and a reference voltage signal, which control unit has at least one of a line drop compensation function, an under-excitation limitation function, an over-excitation limitation function, a power factor regulation function, an armature winding over-current compensation function and a cross-current compensation function. The field control apparatus includes a detector as a common signal source for detecting active power and reactive power components at an output terminal of the generator and means responsive to the output of the detector for performing scalar operation in accordance with a function of the added compensation/control function described above. An output of the operating means is added to the differential signal as an added function signal to control the field current for excitation of the field winding.

    摘要翻译: 一种具有励磁绕组的发电机的现场控制装置,包括端子电压控制单元,用于根据发电机的端子电压信号与参考电压信号之间的差值控制发电机的励磁电流,该控制单元至少具有 线路补偿功能,励磁限制功能,过励磁限制功能,功率因数调节功能,电枢绕组过电流补偿功能和交叉电流补偿功能之一。 现场控制装置包括作为公共信号源的检测器,用于在发生器的输出端子处检测有功功率和无功功率分量,并且响应于检测器的输出,根据附加补偿/补偿的函数进行标量运算的装置, 上述控制功能。 操作装置的输出作为附加功能信号加到差分信号上,以控制用于励磁绕组的励磁电流。

    Control system for AC motor/generator of secondary AC excitation type
    7.
    发明授权
    Control system for AC motor/generator of secondary AC excitation type 失效
    二次交流励磁型交流电机/发电机控制系统

    公开(公告)号:US4742288A

    公开(公告)日:1988-05-03

    申请号:US915392

    申请日:1986-10-06

    IPC分类号: H02J3/40 H02P9/10 H02P1/26

    CPC分类号: H02J3/40 H02P9/10 H02P2101/10

    摘要: A control system for controlling the load of an AC motor/generator of secondary AC excitation type connected to a power system in parallel to at least a synchronous machine. The AC motor/generator has the secondary excitation winding thereof controlled in the amount of excitation so as to generate an output in accordance with an external output command. In the case of variation of power flow between the power system and the synchronous machine, the output command is corrected in accordance with the variation, and the amount of the secondary excitation is controlled by the corrected output command, whereby the variation of power flow between the power system and the synchronous machine is absorbed by the AC motor/generator thereby to prevent the synchronous machine from stepping out.

    摘要翻译: 一种用于控制与至少同步电机并行连接到电力系统的二次交流励磁型交流电动机/发电机的负载的控制系统。 交流电动机/发电机的次级励磁绕组被控制在励磁量中,以便根据外部输出指令产生输出。 在电力系统和同步电机之间的功率流的变化的情况下,根据变化来校正输出命令,并且通过校正的输出命令控制次级激励的量,由此, 电力系统和同步电机被交流电动机/发电机吸收,从而防止同步电机走出。