Abstract:
The techniques described herein allow a wind turbine generator system to automatically capture voltage waveform data corresponding to a voltage disturbance event. Data corresponding to a period preceding the voltage disturbance event, during the event and a period of time after the event are captured and stored for further analysis. The sampling rate is relatively high compared to the frequency of the power provided by the generators.
Abstract:
A household appliance including at least one current sensor for measuring a fault current occurring in the appliance. A safety device which triggers a safety measure in the appliance in response to a predetermined detected fault current value.
Abstract:
An earth leakage breaker includes a main contact, a switch mechanism, an operating handle, a leakage tripping device and an over-current tripping device having an earth-leakage-detection circuit disposed in a main-body case. A power-supply line connects the earth-leakage-detection circuit to the main circuit for supplying voltage between phases of the main circuit as a power source of the earth-leakage-detection circuit. Further, a test switch is provided for turning on and off a power-supply circuit of the power-supply line connected to the earth-leakage-detection circuit, and an operation of the test switch is linked to an ON/OFF operation of the switch mechanism.
Abstract:
A load drive circuit includes a plurality of control sections for drive controlling of a drive switching element while protecting the drive switching element from a predetermined abnormality status, and a current blocking switching element being provided in at least any of a path between the control sections and a power source and a path between the control sections and a ground. When an input to an input circuit is OFF, a current flowing to a gate drive circuit for on/off driving of the drive switching element becomes an OFF state, the driving switching element becomes an OFF state, and the input circuit causes each current blocking switching element to be an OFF state to block dark current.
Abstract:
A driver circuit for a transistor provides a soft start feature where pulses provided to the transistor are varied in duration during startup. The driver also provides an overcurrent protection feature for disabling a driver output for a safe period of time when an overcurrent condition is detected. The driver circuit includes an oscillator that produces a saw tooth wave and a narrow width pulse train for determining pulse width and dead time, respectively. The driver circuit may be used in half-bridge or full-bridge drivers.
Abstract:
A GFCI device which has reverse wiring protection is provided where no power is present at the face terminals even when the device is reverse wired. The device has a pair of movable bridges connected to its terminals. The terminal bridge pair makes contact with the load and face terminals providing power to these terminals when the device is reset. The device also has a reset lockout feature that prevents it from being reset after having been tripped if the circuit interrupting portion of the device is non-operational.
Abstract:
A system and method is provided for monitoring the operating condition of a pump by evaluating fault data encoded in the instantaneous current of the motor driving the pump. The data is converted to a frequency spectrum which is analyzed to create a fault signature having fault attributes relating to various fault conditions associated with the pump. The fault signature is then input to a neural network that operates in conjunction with a preprocessing and post processing module to perform decisions and output those decisions to a user interface. A stand alone module is also provided that includes an adaptive preprocessing module, a one-shot unsupervised neural network and a fuzzy based expert system to provide a decision making module that operates with limited human supervision.
Abstract:
An electrical distribution board that stores terminals of a signal cable connected to a communication network and an electrical power cable connected to an electrical distribution cable, the electrical distribution board comprising: an in-building electrical distribution breaker inserted between the electrical power cable and the in-building distribution cable; a gateway that interfaces the communication network with the in-building network; and a plurality of optical repeaters, each having a bi-directional conversion function between an electrical signal and an optical signal between an electrical signal input/output terminal and an optical signal input/output terminal, and having an electrical signal input/output terminal that is connected to an electrical signal input/output terminal for in-building network connection of the gateway, wherein the optical signal input/output terminal is connected to an optical fiber cable of the in-building network. In addition, junction boxes, outlet boxes, plugs with electrical codes, outlet box terminal boards, table taps and the like are prepared to form an in-building network. In-building equipment can be connected to the outlet boxes and the table taps.
Abstract:
In a load for testing an energy production device, such as a fuel cell, a technique is provided for sensing one or more operational parameters for each of a plurality field effect transistors. Analog and digital feedback are provided to adjust the control signal to the FETs to ensure that each remains within its individual safe operating area. The technique preferably takes all of the various operational parameters into account to determine if any individual FET is approaching the SOA boundary, and prevent that single FET from leaving the SOA while continuing to manage the operation of the entire load.
Abstract:
A relay arcing protection arrangement for a relay of a type including an electromagnetic coil adapted to be connected to a control circuit and effect an opening or closing of at least two electrically conducting contactors in response to a transition signal from the control circuit, including electronic circuit means to detect arcing across the contactors, and to effect activation of a solid state current connection means providing a parallel current pathway to the electrical connectors when arcing is detected during such a selected period of time after activation.