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公开(公告)号：US4978897A
公开(公告)日：1990-12-18
申请号：US514896
申请日：1990-04-26
CPC分类号： H02P3/18 , H02P27/026
摘要： An electric motor has first, second and third stator windings supplied by a source of alternating voltage having three phases A, B and C, respectively. A separate thyristor switch assembly couples each stator winding to an alternating voltage phase when said switch means is rendered conductive by a trigger signal. When the speed of the motor is above a first predefined level, the thyristor switch assemblies are triggered, in response to the polarity of the voltage between phases A and B being opposed to the polarity of back emf voltage induced across the third winding, to apply current through said first and second stator windings. However, when the speed of the motor is below the first predefined level, the thyristor switch assemblies are triggered, in response to the polarity of the voltage betwen phases B and C being opposed to the polarity of back emf voltage induced across the third winding, to apply current through said second and third stator windings. Subsequently when the speed of the motor further decreases below a second predefined level, current is applied through said second and third stator windings during every cycle of the voltage between phases B and C.
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公开(公告)号：US07135833B2
公开(公告)日：2006-11-14
申请号：US11261352
申请日：2005-10-28
IPC分类号： H02P3/18
CPC分类号： G02B21/16 , G01J1/04 , G01J1/0411 , G01J1/0414 , G01J1/0429 , G01J1/044 , G01J1/0455 , G01J1/0462 , G01N21/956 , G02B17/06 , G02B17/061 , G02B21/04
摘要： A method and apparatus for braking an AC motor in the higher portion of its speed range includes substantially reducing flux before applying reverse torque commands to brake the motor. A DC link bus regulator is employed to prevent increases in bus voltage and frequency.
摘要翻译： 用于在其速度范围的较高部分中制动AC电动机的方法和装置包括在施加反向转矩命令以制动电动机之前大幅减少通量。 采用DC链路总线调节器来防止总线电压和频率的增加。
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公开(公告)号：US4916370A
公开(公告)日：1990-04-10
申请号：US343439
申请日：1989-04-26
CPC分类号： H02P3/18
摘要： An electric motor is braked by applying pulses of current to a winding of the motor creating a negative torque which slows the motor. In order to detect when the motor has stopped and as a consequence, when to discontinue applying the current pulses, a periodic determination is performed as to whether the back emf voltage induced in a winding of the motor is within a range of defined values, such as between a positive reference voltage level and a negative reference voltage level. The application of pulses of current is terminated a given interval from when a predetermined number of consecutive determinations all indicate that the back emf voltage is within the range. The length of the given interval is derived from the amount of time between when the electricity began to be applied to brake the motor and the occurrence of the predetermined number of consecutive determinations.
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4.发明授权公开(公告)号：US07268514B2
公开(公告)日：2007-09-11
申请号：US11002011
申请日：2004-11-30
CPC分类号： B66B5/0031 , B66B1/30
摘要： A method and apparatus for stopping an AC motor that is controlling a load while detecting mechanical brake slippage of a mechanical brake for holding the load against movement includes a controller for decreasing torque-producing current commands from the drive while a speed regulator is commanding zero speed, sensing movement of the load while the speed regulator is commanding zero speed, detecting movement of the load past a pre-determined distance limit, and increasing torque to support the load and prevent further movement of the load. The controller will again decrease torque-producing current commands from the drive, and again checking for movement of the load, and upon sensing no load movement upon reaching zero torque, then shutting off the motor.
摘要翻译： 一种用于在检测用于保持负载抵抗运动的机械制动器的机械制动器滑动的同时控制负载的AC电动机的停止方法和装置包括用于在速度调节器指令零速度时减少来自驱动器的转矩产生电流命令的控制器 在速度调节器指令零速度时检测负载的运动，检测负载的运动超过预定的距离极限，以及增加转矩以支持负载并防止负载的进一步移动。 控制器将再次降低来自驱动器的扭矩产生电流指令，并再次检查负载的运动，并且在达到零转矩时检测到无负载运动，然后关闭电机。
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公开(公告)号：US5187419A
公开(公告)日：1993-02-16
申请号：US695870
申请日：1991-05-06
申请人： Robert J. DeLange
发明人： Robert J. DeLange
摘要： An electric induction motor is connected by a switch means to a source of three-phase alternating electricity. The speed of the motor is determined by detecting when the source voltage a zero crossing and thereafter sensing the polarity of the back emf voltage induced in each winding of the motor when the switch means is non-conductive. After several zero crossings a set of polarity samples has been produced from each winding. The motor speed is determined by detected the occurrence of a predefined relationship among samples in each set. For example, the speed is in the range of fifty to about thirty-eight percent of full synchronous speed when three consecutive samples from one winding all have the same polarity. The occurrence of the predefined relationship among back emf polarity samples can be used to control the braking of the motor.
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6.发明授权
公开(公告)号：US5977741A
公开(公告)日：1999-11-02
申请号：US193773
申请日：1998-11-17
申请人： Robert J. DeLange , David J. Cisler
发明人： Robert J. DeLange , David J. Cisler
IPC分类号： H02P7/628
摘要： A method and apparatus for minimizing motor instability under no load conditions, the method including identifying instability by comparing consecutive current half cycle periods and, where the difference between half cycle periods is sufficiently large, determining that instability exists and modifying controller modulating waveforms by reducing waveform magnitude until stability is achieved. Preferably the apparatus for achieving stability includes only a single current zero crossing sensor to minimize hardware costs.
摘要翻译： 一种用于在无负载条件下最小化电机不稳定性的方法和装置，所述方法包括通过比较连续的当前半周期周期来识别不稳定性，并且其中半周期周期之间的差足够大以确定存在不稳定性并且通过减少波形来修改控制器调制波形 达到稳定。 优选地，用于实现稳定性的装置仅包括单个电流过零传感器以最小化硬件成本。
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公开(公告)号：US07960938B2
公开(公告)日：2011-06-14
申请号：US11018753
申请日：2004-12-21
申请人： Robert J. DeLange
发明人： Robert J. DeLange
IPC分类号： H02P27/04
摘要： A motor drive unit includes a voltage inverter, a controller, and reconnect logic. The voltage inverter provides motor drive signals to an associated motor. The controller is operable to generate demand signals for at least two control axes for controlling the voltage inverter. The reconnect logic is operable to direct the controller to inject a current into a first control axis. The reconnect logic is further operable to monitor a voltage of a second control axis to detect zero crossings and determine a speed of the associated motor based on the detected zero crossings.
摘要翻译： 电机驱动单元包括电压逆变器，控制器和重新连接逻辑。 电压变频器向相关电机提供电机驱动信号。 控制器可操作以产生用于控制电压逆变器的至少两个控制轴的需求信号。 重新连接逻辑可操作以引导控制器将电流注入第一控制轴。 重新连接逻辑还可操作以监测第二控制轴的电压以检测过零点，并且基于检测到的过零点确定相关电动机的速度。
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公开(公告)号：US4996469A
公开(公告)日：1991-02-26
申请号：US495018
申请日：1990-03-16
摘要： A three-phase motor controller includes a bidirectional thyristor switch to couple each phase of an electrical supply to a motor. The motor is started by rendering the thyristors conductive during successively greater portions of each cycle of AC electricity from the supply. In order to reduce the cooling requirements of the controller, a contactor is connected in parallel with the thyristors to provide apply electricity to the motor once it reaches full speed. When the controller receives a signal to stop the motor, the contactor is deactivated and the controller goes through a sequence to synchronize the thyristor triggering to the AC electricity. The synchronizing process provides a smooth transition from contractor control back to thyristor control of the application of electricity to the motor. Once thyristor control resumes, the controller executes a triggering routine which decreases the voltage applied to the motor and produces a braking effect.
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