Abstract: An overvoltage suppression device which suppresses overvoltage that occurs when breakers which turn on/off the connection between a power source bus and a power transmission line, are turned on after the breakers are turned off. The overvoltage suppression device measures the waveform of voltage on the side of the power source and the voltage on the side of the power transmission line, and extracts the waveform of a component in a predetermined frequency band on the basis of the waveform obtained by multiplying the wave shape of the voltage on the side of the power source by the waveform of the voltage on the side of the power transmission line. The breakers are turned on on the basis of a cycle wherein the waveform is peaked.

Abstract: According to one embodiment, there is provided an inrush current suppression apparatus that suppresses an inrush current generated when shunt capacitors are connected to a power system. The apparatus includes a power supply voltage measurement unit measuring a power supply voltage, a circuit breaker current measurement unit measuring a circuit breaker current, a residual voltage polarity determination unit determining the polarities of three phases of a residual voltage, a specific phase determination unit determining a specific phase, a closing phase detector detecting a closing phase, and a circuit breaker closing unit closing the circuit breaker in the closing phase.

Abstract: According to one embodiment, there is provided an inrush current suppression apparatus that suppresses an inrush current generated when shunt capacitors are connected to a power system, the apparatus including a voltage measurement unit measuring power source voltages, a current measurement unit measuring circuit breaker currents, a polarity determination unit determining the polarities of residual voltages, a phase section detector detecting a phase section in which the polarities of the residual voltages match the polarities of the power source voltages, and a circuit breaker closing unit closing the circuit breaker within the phase section.

Abstract: A residual magnetic flux estimation device 1 includes a DC power-source control device 11 which controls a DC power source 300 to apply a DC voltage across two terminals of a ? connection that is a secondary winding or a tertiary winding, a voltage measuring device 12 which measures a terminal voltage at the primary side of a three-phase transformer 200, a computing device 13 that determines a phase having a high voltage between the two phases other than the phase to which the voltage is applied, and a residual magnetic flux measuring device 14 that measures a phase-to-phase residual magnetic flux between the two phases other than the high-voltage phase, and estimates a measured value of the phase-to-phase residual magnetic flux as a maximum residual magnetic flux in the measurement-target three-phase transformer.

Abstract: To suppress the magnetizing inrush current occurring when supplying power of three phases of the transformer are performed simultaneously using three single-phase circuit breakers or a non-phase segregated operation-type circuit breaker, without providing a circuit breaker with a resistor or other equipment. A magnetizing inrush current suppression method for transformer suppresses a magnetizing inrush current occurring at the start of energizing of a three-phase transformer 300, when a three-phase power supply 100 is input to a terminal of each phase by means of a three-phase circuit breaker 200.

Abstract: A first calculation part calculates the phase-to-phase steady-state magnetic flux of the three phases of the power supply. A second calculation part calculates the phase-to-phase residual magnetic flux of the three phases in the primary windings side of the transformer when the circuit breakers interrupt the transformer. A phase detection part detects a voltage phase at which polarity and magnitude of the calculated steady-state magnetic flux and residual magnetic flux coincide. Closing control part firstly causes only the circuit breakers of the two phases to close at the detected voltage phase, and then causes the circuit breaker of the remaining one phase to close.

Abstract: A switching controller for circuit breaker in which a switching control arithmetic operation unit performs arithmetic operations to determine for each circuit breaker a synchronous delay count value which is sent to each switching command control unit of the corresponding circuit breaker, which upon receiving a switching command signal from a superordinate device, counts the synchronous delay count value D, to turn on a semiconductor switch of the switching command output unit after counting completes. The switching command signal (circuit breaker drive current) is output after the synchronous switching control to the circuit breaker drive coil of the circuit breaker. The switching controller can implement cost saving and space saving, even if switching of a circuit breaker in a lower branch system, such as a power distribution system, is controlled.

Abstract: In some embodiments, a method is disclosed that includes measuring a waveform of a power source side voltage of a circuit breaker; measuring a waveform of a transmission line side voltage of the circuit breaker; calculating a waveform of a voltage between contacts of the circuit breaker that is a difference between the waveform of the power source side voltage and the waveform of the transmission line side voltage; calculating a waveform of an absolute value of the waveform of the voltage between contacts; extracting a waveform of a component in a frequency band which is lower than a frequency of the power source and higher than a frequency of a DC component from the waveform of the absolute value; detecting a cycle of the extracted waveform; and closing the circuit breaker based on the cycle.

Abstract: An overvoltage suppression device which suppresses overvoltage that occurs when breakers which turn on/off the connection between a power source bus and a power transmission line, are turned on after the breakers are turned off. The overvoltage suppression device measures the waveform of voltage on the side of the power source and the voltage on the side of the power transmission line, and extracts the waveform of a component in a predetermined frequency band on the basis of the waveform obtained by multiplying the wave shape of the voltage on the side of the power source by the waveform of the voltage on the side of the power transmission line. The breakers are turned on on the basis of a cycle wherein the waveform is peaked.

Abstract: To suppress the magnetizing inrush current occurring when supplying power of three phases of the transformer are performed simultaneously using three single-phase circuit breakers or a non-phase segregated operation-type circuit breaker, without providing a circuit breaker with a resistor or other equipment. A magnetizing inrush current suppression method for transformer suppresses a magnetizing inrush current occurring at the start of energizing of a three-phase transformer 300, when a three-phase power supply 100 is input to a terminal of each phase by means of a three-phase circuit breaker 200.

Abstract: The MPU for switching control arithmetic operation 210 in the switching control arithmetic operation unit 200 performs arithmetic operations to determine a predetermined delay time (synchronous delay count value D) for each circuit breaker 1100. The synchronous delay count value is sent to each switching command control unit 400 of the corresponding circuit breaker. The hardware counter 20 of the switching command output control unit 450, for the switching command signal received from the superordinate device 2000, counts the synchronous delay count value D, which is the delay time. When the semiconductor switch of the switching command output unit 10 turns ON after counting completes, the switching command signal (circuit breaker drive current) after the synchronous switching control is output to the circuit breaker drive coil 1110 of the circuit breaker 1100.

Abstract: To provide a magnetizing inrush current suppression device for transformer and control method of same, which accurately calculates the residual magnetic flux when a transformer installed in a non-solidly earthed system, is interrupted by circuit breakers, and which enables suppression of the magnetizing inrush current occurring when three single-phase circuit breakers or single-phase circuit breakers are used for simultaneously supplying power to three phases of the transformer, without providing a circuit breaker with a resistor or other equipment to enlarge the circuit breaker.

Abstract: In a wiper arm, a retainer has a longitudinal base wall and side walls extending from opposite side edges of the longitudinal base wall, so that the retainer has substantially a U-shaped cross section that opens toward a wiping surface. A first washer nozzle is mounted at a substantially intermediate portion of the retainer and a second washer nozzle is mounted at an end of the retainer. The first and second washer nozzles have a first engagement portion formed with either a projection or a recessed portion. The side walls have a second engagement portion formed with the opposite of the first engagement portion. The first and second engagement portions interlock with each other, so the nozzles are secured between the side walls.

Abstract: A water-in-oil emulsion explosive characterized by containing an ethylene vinyl acetate copolymer. It has excellent long-term stability. Even when stored under a load for as long as about one year, the explosive is less apt to suffer a decrease in explosive performance and coagulates only slightly in such a degree that it comes to have weakly coherent partial coagulates which can be easily disaggregated. Even after long-term storage, charging with the explosive can be easily conducted with a charger. Since the explosive has excellent water resistance, it is suitable also for blasting in a water hole.

Abstract: The wiper pivot unit for smoothly absorbing a load applied from the outside of a vehicle. The wiper pivot (1) has a pivot shaft (3), a pivot holder (4) and a toothed washer (5). The pivot shaft has a small-diameter section (31) and a large-diameter section (32). The toothed washer is fitted on the large-diameter section to constrict it with a predetermined force. The toothed washer slips off the large-diameter section when a load of a predetermined value or more acts upon the pivot shaft. When the toothed washer is shifted to the small-diameter section, the pivot shaft descends smoothly along the pivot holder.

Abstract: In a wiper arm, a retainer has a longitudinal base wall and side walls extending from opposite side edges of the longitudinal base wall, so that the retainer has substantially a U-shaped cross section that opens toward a wiping surface. A first washer nozzle is mounted at a substantially intermediate portion of the retainer and a second washer nozzle is mounted at an end of the retainer. The first and second washer nozzles have a first engagement portion formed with either a projection or a recessed portion. The side walls have a second engagement portion formed with the opposite of the first engagement portion. The first and second engagement portions interlock with each other, so the nozzles are secured between the side walls.

Abstract: A wiper device is located between a vehicle rear door and a rear window, which is opened independently from the door. An actuator having an output shaft is fixed to the rear door. A pivot disk is fixed to the output shaft. The pivot disk has a coupler hole. The actuator pivots the coupler hole in a predetermined angle range. A pivot shaft having a wiper arm is supported by the rear window glass. A crank lever having a coupler pin is fixed to the pivot shaft. When the rear window glass is closed with the coupler pin outside of the movement range of the coupler hole, engagement between the coupler pin and the coupler hole moves the coupler pin to the angle range of the coupler hole. Accordingly, the crank lever is positively coupled to the pivot disk by a simple structure.

Abstract: Test pattern data is recorded on a track of the optical disc, and the other pattern data is recorded on the neighboring track. A focus bias value providing the minimum jitter amount when the test pattern data is reproduced with varying the focus bias, is obtained. Just focusing condition is attained by the focus servo using the focus bias. When the test pattern data is reproduced, the data of these neighboring track is also reproduced simultaneously because the pattern data of the type different from the test pattern data is also recorded on the neighboring track. Particularly, under the defocusing condition, crosstalk amount becomes larger because the beam shape is distorted. With reference to jitter amount, such a mistake that the defocusing condition is erroneously determined as the just focusing condition can be eliminated. That is, the focus servo signal providing the accurate just focusing condition can be obtained.

Abstract: A vehicle control apparatus prevents an unnecessary operation of an electric radiator fan motor 16 when a key switch 17 is turned on. The apparatus includes a main controller in the form of a microcomputer 6 for controlling the motor. A reset element 5 operates to reset the main controller for a predetermined time after the key switch is turned on. An auxiliary controller 9 controls the motor in place of the main controller when the main controller is abnormal. A switch 8 is provided for performing switching between a first condition in which the motor is controlled by the main controller and a second condition in which the motor is controlled by the auxiliary controller. An abnormality detector 7 detects an abnormality of the main controller and switches over the switch into the second condition when there is an abnormality of the main controller. An AND gate 10 is provided for disabling the output of the auxiliary controller during the time when the main controller is reset by the reset element.

Abstract: Herein disclosed are both waste gas circulation method and system for effectively recovering waste heat from an on-strand type sintering apparatus which has its sintering and cooling zones extending continuously along a horizontal strand. The hottest waste gases coming from the final stage of the sintering zone and the front stage of the cooling zone, in which the sintering reaction of a charge mixture is completed, are subjected to heat recovery, and sulfur oxides in the hottest gases are prevented from condensing on the water pipe or pipes of a waste-heat boiler by preheating the water, which is supplied for the heat recovery, with the still hot waste gases coming from the downstream half of the cooling zone. The heat of the still hot waste gases are exchanged with cold water so that this water may be heated into hot water. On the other hand, the heat of the hottest gases is exchanged with steam so that this steam may be heated into superheated steam.