摘要:
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.
摘要:
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. The device has steady-state magnetic flux calculation means for calculating the line-to-line steady-state magnetic flux of three-phase power supplies, residual magnetic flux calculation means for calculating the primary line-to-line residual magnetic flux of the transformer when the circuit breakers interrupt the transformer, phase detection means for detecting a phase at which the polarity and magnitude of the calculated steady-state magnetic flux and residual magnetic flux coincide for each line-to-line. Closing control means firstly causes only two-phase of the circuit breakers, which are connected with the line-to-line, to close at the detected phase, and then causes the remaining one-phase circuit breaker to close.
摘要:
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.
摘要:
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. A switching controller for circuit breaker and a switching control system for circuit breaker are provided, which 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.
摘要:
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.
摘要:
A roller chain, having an elastic annular member being fitted adjacent each end of a pin and between a pin link plate and a roller link plate for sealing lubricating oil present in the space between the pin and the bushing, comprises a bushing extended on each end thereof so as to form an extended portion projecting outwards from the roller link plate by a length slightly smaller than the thickness of said annular member, said extended portion being provided with a tapered face on the outer periphery thereof, and said annular member being fitted on said outer periphery so as to be in contact with said tapered face and maintained in lightly pressurized contact with the pin link plate and the roller link plate.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.