-
1.发明授权Ground fault detection and protection method for a variable speed ac electric motor 失效变速交流电动机的接地故障检测和保护方法
公开(公告)号：US5945802A
公开(公告)日：1999-08-31
申请号：US966289
申请日：1997-11-07
IPC分类号： G01R31/02 , F04D15/00 , G01R31/327 , G01R31/333 , G01R31/34 , H02M7/529 , H02P23/00 , H02P23/08 , H02P27/06 , H02P27/08 , H02P5/40
CPC分类号： G01R31/025 , F04D15/0066 , G01R31/343 , H02P23/0077 , H02P23/08 , H02P27/08 , H02H11/005 , H02H7/0833
摘要： A method and apparatus for detecting the presence of a ground leakage path in an electric motor system including an alternating current (ac) electric motor coupled for receiving electric power from a switching inverter of the type having, for each phase of the motor, a pair of serially connected electronic switching devices connected between relatively positive and negative direct current (dc) voltage buses with the switching devices being alternately gated into and out of conduction for providing switched electric power to the motor. The inverter includes a current detector for detecting current in the relatively negative voltage bus. The method comprises initially applying a gating pulse each time the motor is energized to the switching device of each phase connected to the negative voltage bus and identifying a ground leakage path when such gating pulse produces current at the current detector. Preferably, the first gating pulse is of very short time duration and the process of applying gating pulses is repeated for each of a plurality of continuously increasing pulse widths until a selected maximum width is attained without generating current. Thereafter, the motor is started in a conventional manner.
摘要翻译： 一种用于检测电动机系统中存在接地泄漏路径的方法和装置，该电动机系统包括用于接收来自具有对于电动机的每相的一对的开关变换器的电力的交流（ac）电动机， 连接在相对正和负直流（dc）电压总线之间的串联电子开关装置，其中开关装置交替地选通和导通，以向电动机提供开关电力。 逆变器包括用于检测相对负电压总线中的电流的电流检测器。 该方法包括：每当电动机通电到连接到负电压总线的每相的开关装置时首先施加选通脉冲，并且当这种门控脉冲在电流检测器处产生电流时识别接地泄漏路径。 优选地，第一选通脉冲具有非常短的持续时间，并且对于多个连续增加的脉冲宽度中的每一个重复施加门控脉冲的处理，直到获得所选择的最大宽度而不产生电流。 此后，以常规的方式起动电动机。
-
公开(公告)号：US06254353B1
公开(公告)日：2001-07-03
申请号：US09395634
申请日：1999-09-14
IPC分类号： F04B4906
CPC分类号： F04D15/0245 , F04D15/0077 , F04D15/0281
摘要： A submersible pumping system which, in one embodiment, includes a motor, a pump and a control circuit, or unit, coupled to the motor for controlling the operation of the motor is described. Using motor and sensor signals, the control unit detects various conditions within the pumping system and alters motor operation. In an exemplary embodiment, the control unit initiates an oscillation sequence of applying a forward torque for a first preselected period of time, applying a reverse torque for a second preselected period of time, and then repeating the torque applying steps a selected number of times to eliminate an obstruction from the pump.
摘要翻译： 描述了一种在一个实施例中的潜水泵送系统，其包括马达，泵和控制电路或联接到马达上的控制马达运行控制单元。 使用电机和传感器信号，控制单元检测泵送系统内的各种条件，并改变电机运行。 在示例性实施例中，控制单元启动在第一预选时间段内施加正向转矩的振荡序列，在第二预选时间段施加反向转矩，然后将选定次数的转矩施加步骤重复到 消除泵的阻塞。
-
搜索结果
2 条记录 (耗时 0.017 秒)
