专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

1. 发明申请

US20130285671A1 METHOD AND APPARATUS FOR PROTECTING POWER TRANSFORMERS FROM LARGE ELECTRO-MAGNETIC DISTURBANCES 有权
标题翻译：用于保护大型电磁干扰电力变压器的方法和装置
公开(公告)号：US20130285671A1
公开(公告)日：2013-10-31
申请号：US13736927
申请日：2013-01-08
申请人： GARY R. HOFFMAN , EDWARD S. KWON , HONG CAI
发明人： GARY R. HOFFMAN , EDWARD S. KWON , HONG CAI
IPC分类号： G01R31/02
CPC分类号： G01R31/027 , G01R31/1227 , H02H3/093 , H02H3/52 , H02H5/005 , H02H7/04 , H02H7/0455
摘要： A protective system far a power transformer having a neutral line connected to ground where large currents can flow in the neutral line due to electro-magnetic disturbances. The system includes circuitry for: (a) sensing the current level in the neutral line and whether it exceeds a predetermined threshold for a predetermined period; and (b) sensing and processing the harmonic content of the load current and determining the existence of certain relationships of the “even” and “odd” harmonics. Signals, including alarms, indicative of excessive conditions are produced. The system may also include circuitry for sensing the load current level and generating a signal alarm if the load level is above a giver) value when the harmonics and the DC current have values in excess of certain predetermined values.
摘要翻译：远离电力变压器的保护系统，其中性线连接到地面，由于电磁干扰，大电流可能在中性线中流动。该系统包括用于以下步骤的电路：（a）感测中性线中的电流电平以及它是否在预定时间段内超过预定阈值; 和（b）感测和处理负载电流的谐波含量并确定“偶数”和“奇数”谐波的某些关系的存在。产生指示过度状况的信号，包括报警。当谐波和DC电流具有超过某些预定值的值时，该系统还可以包括用于感测负载电流水平并且如果负载水平高于发生器值则产生信号报警的电路。

2. 发明授权

US07417411B2 Apparatus and method for monitoring tap positions of load tap changer 有权
标题翻译：用于监测有载分接开关的分接头位置的装置和方法
公开(公告)号：US07417411B2
公开(公告)日：2008-08-26
申请号：US11520821
申请日：2006-09-13
申请人： Gary R. Hoffman , Thomas C. Tennille
发明人： Gary R. Hoffman , Thomas C. Tennille
IPC分类号： G05F1/147
CPC分类号： G05F1/147
摘要： A load tap changer (LTC) having a plurality of windings is coupled to one of the primary and secondary windings of a power transformer in order to regulate the output voltage of the power transformer. The LTC includes a plurality of taps physically and electrically connected to the LTC windings and the transformer's output voltage is increased/decreased by moving along the taps a contacting element whose movement is controlled by a rotating shaft driven by a motor. The tap being contacted is determined by sensing the direction and number of shaft rotations and by checking the number of shaft rotations specified to go from a tap to the next tap being contacted. The time for a full rotation of the shaft is also measured. Also, the temperature of the tanks containing the LTC taps and the power transformer is measured for each tap position.
摘要翻译：具有多个绕组的有载分接开关（LTC）被耦合到电力变压器的一个和次级绕组中的一个，以便调节电力变压器的输出电压。 LTC包括物理和电连接到LTC绕组的多个抽头，并且变压器的输出电压通过沿着抽头移动一个接触元件来增大/减小，接触元件的移动由电动机驱动的旋转轴控制。接触的水龙头通过感测轴旋转的方向和数量以及通过检查指定从一个水龙头到另一个水龙头被接触的轴旋转次数来确定。也测量轴完全旋转的时间。此外，对于每个分接位置，测量包含LTC抽头和电力变压器的箱体的温度。

3. 发明授权

US07323852B2 Sensing load tap changer (LTC) conditions 有权
标题翻译：感应式有载分接开关（LTC）条件
公开(公告)号：US07323852B2
公开(公告)日：2008-01-29
申请号：US11520542
申请日：2006-09-13
申请人： Gary R. Hoffman
发明人： Gary R. Hoffman
IPC分类号： G05F1/16 , G05B24/02
CPC分类号： G05F1/147
摘要： A load tap changer (LTC) having a plurality of windings is coupled to one of the primary and secondary of a power transformer in order to regulate the output voltage of the transformer. The LTC includes a plurality of taps physically and electrically connected to and along the windings and a contacting element is selectively moved along the taps to increase or decrease the output voltage of the transformer. The power transformer and the LTC windings are placed in a main tank and the taps are placed in an LTC tank. The temperature in the main tank and the temperature in the LTC tank are monitored by means of first and second temperature probes whose outputs are used to sense the temperature differential (TDIFF) between the main tank and the LTC tank and to determine if the LTC tank temperature exceeds the main tank temperature for a period of time exceeding a specified time period. Also included is circuitry for sensing the rate of change of TDIFF and determining if it exceeds a predetermined value.
摘要翻译：具有多个绕组的有载分接开关（LTC）被耦合到电力变压器的一次和次级中的一个，以便调节变压器的输出电压。 LTC包括物理和电连接到绕组并沿着绕组的多个抽头，并且接触元件选择性地沿着抽头移动以增加或减小变压器的输出电压。电源变压器和LTC绕组放置在主箱中，并将水龙头放置在LTC箱中。通过第一和第二温度探头来监测主罐中的温度和LTC罐中的温度，其第一和第二温度探头的输出用于感测主罐和LTC之间的温差（T D D D F F）并确定LTC油箱温度是否超过主油箱温度超过规定时间段的时间。还包括用于感测T DIFF 的变化率并确定其是否超过预定值的电路。

4. 发明授权

US06222714B1 Microprocessor based setting group controller for protective relay operations 有权
标题翻译：用于保护继电器操作的基于微处理器的设置组控制器
公开(公告)号：US06222714B1
公开(公告)日：2001-04-24
申请号：US09526218
申请日：2000-03-15
申请人： Gary R. Hoffman
发明人： Gary R. Hoffman
IPC分类号： H02H300
CPC分类号： H02H3/006 , H02H5/04
摘要： A substation for distributing electric power includes protective relays whose trip points are made to be a function of temperature, the protective relays being used to control the opening and closing of circuit breakers for protecting against fault conditions in at least one of the power input and power output portions of the power distribution system. In one embodiment, a temperature probe which is used to sense the temperature at a selected point of the substation supplies the temperature information to a microcontroller which is programmed to set the trip point of selected protective relays as a function of the sensed temperature.
摘要翻译：用于分配电力的变电站包括其跳闸点作为温度的保护继电器，用于控制断路器的断开和闭合的保护继电器用于防止至少一个功率输入和功率中的故障状况输出部分。在一个实施例中，用于感测变电站选定点处的温度的温度探测器将温度信息提供给微控制器，该微控制器被编程为根据检测到的温度来设置所选保护继电器的跳闸点。

5. 发明授权

US4660035A Remote monitoring system 失效
标题翻译：远程监控系统
公开(公告)号：US4660035A
公开(公告)日：1987-04-21
申请号：US737092
申请日：1985-05-23
申请人： Gary R. Hoffman
发明人： Gary R. Hoffman
IPC分类号： G01R11/16 , G01R21/133 , G06M1/274 , G08C19/16
CPC分类号： G01R11/16 , G01R21/133 , G06M1/274
摘要： A wheel is mounted on a rotating shaft and cooperates with at least one pair of inductors fixedly mounted in juxtaposition to the wheel. The wheel has at least one opening formed therein for generating a signal whenever the opening in the wheel is substantially aligned circumferentially with the pair of inductors. An electronic control circuit, responsive to the signal, actuates a remote meter for providing a remote indication of the shaft position. In a preferred embodiment, this improved sensing means is applied to the remote reading of a conventional household electric meter. Two pair of inductors are provided for cooperation with five equiangularly-spaced closed slots formed in the wheel, thereby providing ten signals (or counts) for each complete revolution of the wheel. The wheel is mounted on the shaft of the unit decade dial in the meter. The remote meter comprises a digital counter, responsive to the pulse generated by the electronic control circuit, for providing a remote digital read-out of the accumulated kilowatt hours on the meter.
摘要翻译：车轮安装在旋转轴上，并与至少一对固定安装在车轮上的电感器配合。车轮上至少有一个开口形成在其中，用于当车轮中的开口基本上与该对电感器对齐时产生信号。响应于该信号的电子控制电路致动远程仪表以提供轴位置的远程指示。在优选实施例中，这种改进的感测装置被应用于传统家用电表的远程读取。提供两对电感器用于与车轮中形成的五个等角度间隔的闭合槽配合，从而为车轮的每次完整转动提供十个信号（或计数）。车轮安装在仪表的单位十年表盘的轴上。远程仪表包括数字计数器，响应于由电子控制电路产生的脉冲，用于在仪表上提供累积千瓦小时的远程数字读出。

6. 发明授权

US4518958A Capacitively coupled machine tool safety having a self-test network 失效
标题翻译：具有自检网络的电容耦合机床安全
公开(公告)号：US4518958A
公开(公告)日：1985-05-21
申请号：US345191
申请日：1982-02-02
申请人： William A. Cook , Gary R. Hoffman , William M. Pulford
发明人： William A. Cook , Gary R. Hoffman , William M. Pulford
IPC分类号： B23Q11/00 , F16P3/14 , G05B19/4063 , G08B21/02 , G08B29/14 , H04B5/00 , G08B21/00
CPC分类号： B23Q11/0082 , F16P3/14 , F16P3/148 , G05B19/4063 , G08B21/0247 , G08B29/14 , H04B5/0012 , G05B2219/49157
摘要： A machine tool safety system includes an electric field generator capacitively coupled to a receptor antenna. A self-test network includes a self-test radiating antenna and a circuit arrangement operative to apply a test signal to the self-test antenna. The test signal may be of sufficient strength to induce in the receptor antenna a first excitation signal having a magnitude greater than a first predetermined threshold to verify that the safety system is operative to detect the entry of the field generator carried on an operator's person into a hazard zone proximal to the machine tool. The test signal may be of sufficient strength to induce a second excitation signal greater than a second threshold to verify that the safety system is operative to detect the entry of the field generator into an arming zone spaced from the hazard zone.
摘要翻译：一种机床安全系统包括电容耦合到接收天线的电场发生器。自测网络包括自测辐射天线和可将测试信号施加到自测天线的电路装置。测试信号可能具有足够的强度，以在接收器天线中诱导具有大于第一预定阈值的幅度的第一激励信号，以验证安全系统是可操作的，以检测运营商人携带的场发生器的进入到靠近机床的危险区域。测试信号可能具有足够的强度以引起大于第二阈值的第二激励信号，以验证安全系统是否可操作以检测场发生器进入与危险区间隔开的布防区域。

7. 发明授权

US3963993A Power amplifier using a plurality of parallel connected amplifier elements and having burn-out protection 失效
标题翻译：使用多个并联连接放大器元件并具有保护功能的功率放大器
公开(公告)号：US3963993A
公开(公告)日：1976-06-15
申请号：US546153
申请日：1975-01-31
申请人： Gary R. Hoffman , William P. Rinkers
发明人： Gary R. Hoffman , William P. Rinkers
IPC分类号： H03F1/00 , H03F1/42 , H03F1/52 , H03F3/195 , H03F3/20 , H03F3/213 , H03F3/60 , H03F3/68
CPC分类号： H03F3/211 , H03F1/52 , H03F3/602 , H03F3/68
摘要： A power amplifier includes a plurality of generally identical amplifier elements connected in parallel between input and output transmission lines for phase coherent addition of the signal outputs of each amplifier element. Resistive elements are connected across normally phase identical points on the transmission lines. If the amplifier becomes electrically unbalanced, power is absorbed in the resistive elements, thus protecting the amplifier elements.

8. 发明授权

US08274769B2 Apparatus and method for cooling power transformers 有权
标题翻译：电力变压器冷却装置及方法
公开(公告)号：US08274769B2
公开(公告)日：2012-09-25
申请号：US12802412
申请日：2010-06-07
申请人： Gary R. Hoffman , Jeffrey Anderson
发明人： Gary R. Hoffman , Jeffrey Anderson
IPC分类号： H02H7/04 , H02H5/06 , H01F27/10 , H01F27/12
CPC分类号： H01F27/402 , H01F2027/406
摘要： The cooling system for a power transformer is activated by sensing and processing the frequency characteristic including the harmonic contents, of the inrush current into the transformer, when the transformer is first energized. The cooling system may include motors operating devices such as oil circulating pumps and fans causing a coolant to flow about the power transformer. The cooling system is deactivated by sensing when the transformer is de-energized and when its temperature is below a predetermined level.
摘要翻译：当变压器第一次通电时，通过检测和处理包括谐波含量的入侵变压器的浪涌电流的频率特性来激活电力变压器的冷却系统。冷却系统可以包括马达操作装置，例如油循环泵和风扇，使得冷却剂在电力变压器周围流动。当变压器断电并且当其温度低于预定水平时，冷却系统被去激活。

9. 发明授权

US4532501A Capacitively coupled machine tool safety system 失效
标题翻译：电容耦合机床安全系统
公开(公告)号：US4532501A
公开(公告)日：1985-07-30
申请号：US345193
申请日：1982-02-02
申请人： Gary R. Hoffman
发明人： Gary R. Hoffman
IPC分类号： F16P3/14 , G01V3/08 , G08B21/00
CPC分类号： G01V3/088 , F16P3/14 , F16P3/148
摘要： A safety system for a machine tool is characterized by a capacitively coupled electric field generator (transmitter) and a capacitive receptor antenna. An electrical signal is induced in the capacitive receptor antenna by the action of the electric field. The magnitude of the induced signal is monotonically related to the distance between the electric field generator and the capacitive receptor antenna. When the magnitude of the electrical signal exceeds a predetermined threshold, a machine tool safety indicator is developed.
摘要翻译：用于机床的安全系统的特征在于电容耦合电场发生器（发射器）和电容式接收器天线。通过电场的作用在电容式接收天线中感应出电信号。感应信号的幅度与电场发生器和电容式接收天线之间的距离单调相关。当电信号的大小超过预定阈值时，开发出机床安全指示器。

10. 发明授权

US08260472B2 Cooling system for power transformer 有权
标题翻译：电力变压器冷却系统
公开(公告)号：US08260472B2
公开(公告)日：2012-09-04
申请号：US12381184
申请日：2009-03-09
申请人： Gary R. Hoffman , Jeffrey Anderson
发明人： Gary R. Hoffman , Jeffrey Anderson
IPC分类号： G06F19/00
CPC分类号： H01F27/085 , H01F2027/404
摘要： A system for cooling a power transformer which generates heat, when driving a load, includes cooling devices, such as fans and pumps, located about the transformer, which are powered for circulating a coolant about the transformer. Each cooling device has a motor which is energized in response to given temperature (heat) conditions. In systems embodying the invention, the currents flowing through the motors of cooling devices are sensed and monitored to determine whether the cooling devices are functioning correctly and to substitute functional cooling devices for those which are malfunctioning. Sensing the currents in the motors enables the early detection of fault conditions in the cooling system. It also enables the monitoring of operating conditions and running time of the cooling devices to aid in the maintenance and operation of the cooling system.
摘要翻译：用于冷却在驱动负载时产生热量的电力变压器的系统包括围绕变压器的冷却装置，例如风扇和泵，其用于使变冷器周围的冷却剂循环。每个冷却装置具有响应于给定温度（热）条件而通电的马达。在体现本发明的系统中，感测和监测流过冷却装置的电动机的电流，以确定冷却装置是否正常工作，并将功能冷却装置替换为故障的冷却装置。感测电机中的电流可以早期检测冷却系统中的故障状况。它还能够监测冷却装置的运行状况和运行时间，以帮助冷却系统的维护和运行。

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式