Method of controlling the starting, stopping and speed of an AC
induction motor
    1.
    发明授权
    Method of controlling the starting, stopping and speed of an AC induction motor 有权
    控制交流感应电动机起动,停止和转速的方法

    公开(公告)号:US6163129A

    公开(公告)日:2000-12-19

    申请号:US266549

    申请日:1999-03-11

    CPC分类号: H02P3/18 H02P1/26 H02P27/02

    摘要: A method for controlling the starting, stopping and operation of an AC motor is provided. Each winding of the AC motor is interconnected to an AC source by a thyristor switch and a bypass contactor for providing voltage and current to the AC motor. The method includes a steps of sequently firing a pair of tyristor switches to bring the AC motor to full operating speed. Once at operating speed, the bypass contactors are closed. Upon detection of a voltage drop across a thyristor switch, the thyristor switch is fired immediately to transfer motor current from the bypass contactor to the thyristor switch in order to maintain voltage and current to the AC motor.

    摘要翻译: 提供一种用于控制AC电动机的启动,停止和操作的方法。 AC电动机的每个绕组通过晶闸管开关和用于向AC电动机提供电压和电流的旁路接触器与AC电源互连。 该方法包括随后点燃一对可控硅开关以使AC电动机达到完全运行速度的步骤。 一旦处于运行速度,旁路接触器关闭。 当检测到晶闸管开关上的电压降时,晶闸管开关立即被激发,以将电动机电流从旁路接触器传递到晶闸管开关,以保持对电动机的电压和电流。

    Method and apparatus for predicting winding failure using zero crossing
times
    2.
    发明授权
    Method and apparatus for predicting winding failure using zero crossing times 失效
    使用零交叉时间预测绕组故障的方法和装置

    公开(公告)号:US5488281A

    公开(公告)日:1996-01-30

    申请号:US314472

    申请日:1994-09-28

    IPC分类号: H02P27/02 H02P7/36

    CPC分类号: H02P27/02 G01R31/343

    摘要: A method and apparatus to be used with a motor controller for determining the degree of rotor winding failure and stator winding failure using current zero crossing times of the stator winding currents. An error signal sequence, consisting of phase angle errors between consecutive zero crossings over a sampling period, is generated and analyzed in different regions of interest in either the time or frequency domain, producing signals with varying amplitudes, the signal amplitudes together with other motor parameter measurements being used to determine the degree of rotor winding failure and stator winding failure.

    摘要翻译: 与电机控制器一起使用的方法和装置,用于使用定子绕组电流的当前零交叉时间来确定转子绕组故障和定子绕组故障的程度。 在时域或频域中产生并分析不同感兴趣区域的误差信号序列,包括采样周期内的连续过零点之间的相位角误差,产生具有变化幅度的信号,信号幅度与其他电机参数 用于确定转子绕组故障和定子绕组故障的程度的测量。

    Apparatus and methods for controlling induction motors
    3.
    发明授权
    Apparatus and methods for controlling induction motors 失效
    用于控制感应电动机的装置和方法

    公开(公告)号:US4800326A

    公开(公告)日:1989-01-24

    申请号:US873454

    申请日:1986-06-06

    申请人: Peter J. Unsworth

    发明人: Peter J. Unsworth

    IPC分类号: H02P23/00 H02P5/40

    CPC分类号: H02P23/26 Y02P80/116

    摘要: When induction motors are lightly loaded their power factors and efficiency are poor but in the present invention power factor is controlled regardless of load. An induction motor is connected by way of a triac to a supply. The voltage across the triac is monitored by a comparator for voltage steps which correspond to current turn-off and a signal is developed at the output of an amplifier which represents error from required phase lag. A further comparator and a trigger pulse generator trigger the triac in accordance with the error. An override circuit overrides the control system during starting. A number of further induction motors may be connected in parallel with the motor. Additional circuits deal with problems arising when a three-phase induction motor is connected by three wires only.

    摘要翻译: 当感应电动机轻负载时,其功率因数和效率差,但是在本发明中,无论负载如何,功率因数都被控制。 感应电动机通过三端双向可控硅连接到电源。 三端双向可控硅开关元件上的电压由比较器监测,用于对应于当前关断的电压阶跃,并且在放大器的输出处产生信号,其表示所需相位滞后的误差。 进一步的比较器和触发脉冲发生器根据误差触发三端双向可控硅。 在启动期间,覆盖电路将覆盖控制系统。 多个感应电动机可以与电动机并联连接。 额外的电路处理三相感应电动机仅通过三线连接时出现的问题。

    Method and system of controlling asynchronous contactors for a multi-phase electric load
    4.
    发明授权
    Method and system of controlling asynchronous contactors for a multi-phase electric load 有权
    控制多相电力负载异步接触器的方法和系统

    公开(公告)号:US07224557B2

    公开(公告)日:2007-05-29

    申请号:US10859507

    申请日:2004-06-02

    IPC分类号: H02H3/08

    摘要: Control of an induction motor is carried out to limit damaging arcing stress and mechanical stresses placed on the control contactor assembly and the induction motor resulting from the simultaneous or synchronous breaking and making of contactors employed to connect the windings of the motor to a power supply. Asynchronously connecting the windings to the power supply via the asynchronous or non-simultaneous closing of the contactors of a modular contactor assembly reduces the potentially damaging transient current, the associated torque oscillations, and mechanical stresses. The present invention is particularly applicable to delta motors that are started with its windings in a star or wye configuration followed by the reconnection of the windings in a delta configuration when the motor is at normal running speed.

    摘要翻译: 执行感应电动机的控制以限制由于同时或同步地断开和制造用于将电动机的绕组连接到电源的接触器而导致的控制接触器组件和感应电动机上施加的损坏的电弧应力和机械应力。 通过异步或非同时关闭模块化接触器组件的接触器将绕组异步连接到电源减少潜在的破坏性瞬态电流,相关联的扭矩振荡和机械应力。 本发明特别适用于以马达处于正常运行速度时以三角形配置重新连接绕组的星形或者叶状配置的绕组开始的三角马达。

    Method and apparatus for detecting current delay angle from motor
terminal voltage
    5.
    发明授权
    Method and apparatus for detecting current delay angle from motor terminal voltage 失效
    从电机端子电压检测电流延迟角的方法和装置

    公开(公告)号:US5627447A

    公开(公告)日:1997-05-06

    申请号:US536728

    申请日:1995-09-29

    IPC分类号: H02P23/00 H02P5/40

    CPC分类号: H02P23/26

    摘要: A method and apparatus to be used with an inverter based motor controller for determining current phase angles for the current on a single phase of a three phase AC motor from an inverter generated high frequency phase voltage sequence. The invention detects turn on delay periods and compares phase voltages during consecutive turn on delay periods to determine phase current zero crossing times which can be used along with phase voltage zero crossing times to derive current phase angle information.

    摘要翻译: 一种用于基于逆变器的电动机控制器使用的方法和装置,用于从逆变器产生的高频相电压序列确定三相交流电动机的单相上的电流的电流相位角。 本发明检测接通延迟周期并比较连续导通延迟周期期间的相电压,以确定可以与相电压过零时间一起使用的相电流过零时间以导出当前相位角信息。

    Method for stopping an electric motor
    6.
    发明授权
    Method for stopping an electric motor 失效
    停止电动马达的方法

    公开(公告)号:US4862052A

    公开(公告)日:1989-08-29

    申请号:US165538

    申请日:1988-03-08

    IPC分类号: H02P3/24 H02P3/18

    CPC分类号: H02P3/18

    摘要: An electric motor is braked by sensing the polarity of voltage of the alternating electricity for powering the motor and sensing the polarity of the voltage induced in the motor by the back electromotive force. When these polarities are opposite the electricity is applied to the motor to generate a braking torque. The application of the electricity is stopped a given interval after it begins to be applied during consecutive voltage cycles. This interval is derived from the time period between when braking commenced to when the electricity was applied during consecutive cycle.

    Method and apparatus for motor fault diagnosis
    8.
    发明授权
    Method and apparatus for motor fault diagnosis 有权
    电机故障诊断方法及装置

    公开(公告)号:US06636823B1

    公开(公告)日:2003-10-21

    申请号:US09409452

    申请日:1999-09-30

    IPC分类号: G01R3100

    CPC分类号: G01R31/343

    摘要: A method and apparatus for detecting a stator winding fault in an induction motor includes sampling instantaneous signals from the motor and then deriving sequence components of at least some of the instantaneous signals using a power decomposition technique (PDT), one of the sequence components being a total negative sequence current component. In addition, the method includes calculating an expected negative sequence current based on at least some of the sequence components. Thereafter, the method subtracts the expected negative sequence current from the total negative sequence current to determine a fault negative sequence current, wherein the fault negative sequence current is indicative of the fault. More preferably, the method additionally includes calculating an intrinsic motor negative sequence current based on at least some of the sequence components, and subtracting the intrinsic motor negative sequence current from the fault negative sequence current generated as described above to determine a modified fault negative sequence current. Notably, the method and apparatus are capable of detecting faults that cause a modified fault negative sequence current as low as approximately 0.2% of the full load current.

    摘要翻译: 用于检测感应电动机中的定子绕组故障的方法和装置包括从电动机采集瞬时信号,然后使用功率分解技术(PDT)导出至少一些瞬时信号的序列分量,其中一个序列分量为 总负序电流分量。 另外,该方法包括基于至少一些序列分量来计算预期的负序电流。 此后,该方法从总负序电流中减去预期的负序电流,以确定故障负序电流,其中故障负序电流表示故障。 更优选地,该方法还包括基于至少一些序列分量来计算固有电动机负序电流,并且从如上所述产生的故障负序电流中减去固有电动机负序电流,以确定修正的故障负序电流 。 值得注意的是,该方法和装置能够检测导致修正的故障负序电流低至满负载电流的约0.2%的故障。

    Apparatus and method for braking an electric motor
    9.
    发明授权
    Apparatus and method for braking an electric motor 失效
    用于制动电动机的装置和方法

    公开(公告)号:US4833386A

    公开(公告)日:1989-05-23

    申请号:US103729

    申请日:1987-10-02

    申请人: Peter J. Unsworth

    发明人: Peter J. Unsworth

    IPC分类号: H02P3/20 H02P3/18 H02P3/24

    CPC分类号: H02P3/18

    摘要: An electric motor is coupled to the power lines by thyristors. The motor is braked by triggering the thyristors at the proper times to produce a electro-magnetic field within the motor which opposes the residual magnetic field of the rotor. The proper time to trigger the thyristors is determined by comparing the polarity of the voltage across the power lines to the back emf voltage from the motor. The thyristors are triggered when these two voltages have opposite polarities. The braking circuit also regulates the duty cycle of the thyristors to control the magnitude of the current applied to brake the motor.