Interrupter Module Research Articles

Study on voltage distribution characteristic of a 363 kV fast multi‐break vacuum circuit breaker

Vacuum circuit breaker (VCB) has a longer life and shorter opening time than SF6 circuit breaker, but current single-break VCB cannot be applied in high-voltage power system directly. Here, a fast 363 kV multi-break VCB design is presented and its voltage distribution characteristic and stray capacitors are analysed. A three-dimensional finite-element model of modularised hexa-break VCB composed of 12 vacuum interrupter modules installed on three series connected platforms is developed to calculate the voltage distribution and distributed capacitances. The result shows that the voltage distribution is uneven, and the first break shares the 67.974% of the whole applied voltage. On account of distributed capacitances parameters, an equivalent capacitance model with PSCAD is built to discuss the voltage distribution characteristic at different grading capacitance values, and the optimal grading capacitance value is determined to 10 nF.

DC Interrupting With Self-Excited Oscillation Based on the Superconducting Current-Limiting Technology

A dc circuit breaker (DCCB), which combines a superconducting current-limiting technology and a self-excited oscillation interrupting technology, was proposed. The proposed DCCB includes a superconducting current-limiting module and an interrupter module. The objective of this paper is to investigate the effects of a transverse magnetic field (TMF) on dc interruption based on the self-excited oscillation principle. The dc interruption characteristics of CO2 and SF6 were investigated by applying a TMF of 0 and 200 mT with a puffer-type structure as a benchmark. The experimental results show that applying a TMF of 200 mT can significantly reduce the arcing time compared with a TMF of 0 mT and puffer-type structure. The dc interruption capacity for the SF6 insulation is higher than that for the CO2 insulation in the interrupter module under the same experimental condition. The simulation results of rated voltage of 10 kV show that the superconducting current-limit module limited the short current of 20 kA to less than 1 kA, and the arcing time was 4.5 ms. The results of rated voltage of 200 kV, short current of 30 kA, show that the DCCB only needed to interrupt the limited current of 3.5 kA and the overvoltage was less than 200 kV.

Quenched Resistance Effects on a Superconducting Current-Limiting-Type DC Breaker

Application of a dc circuit breaker (DCCB) using superconducting current-limiting technology can strongly reduce the short-circuit currents that occur in high-voltage dc systems. The superconducting current-limiting-type DCCB includes a superconducting current-limiting module and an interrupter module (IM). The objective of this paper is to determine the effects of the quenched resistance characteristics of the superconductor on dc interruption based on the self-excited oscillation principle. We test the quenched resistance characteristics and the recovery times of two different types of YBCO-coated conductor tapes (with critical currents of 102 and 225 A). The quenched resistance of the 102-A YBCO tape was quenched more rapidly than the 225-A tape, and the quenched resistance of the 102-A tape was higher than that of the 225-A tape. Therefore, the 102-A tape can limit the fault current to a lower level, which results in the reduction in the difficulty of interruption for the IM. The arcing time, the absorbed energy, and the peak current in the ZnO arrester of the IM can also be reduced considerably because the interrupting current is much lower.

Arcing Time of a DC Circuit Breaker Based on a Superconducting Current-Limiting Technology

A dc circuit breaker (DCCB) based on a superconducting current-limiting technology was proposed for the interruption of short-circuit fault currents in high-voltage dc (HVDC) systems. The proposed DCCB includes a superconducting current-limiting module (SCLM), which is used to limit fault currents, and an interrupter module (IM), which uses a self-excited oscillation method to interrupt the limited current. The objective of this paper is to determine methods that reduce the arcing time of the proposed self-excited oscillation-type DCCB. The self-excited oscillation-type circuit breaker alone is generally unable to interrupt the fault current when it exceeds 8 kA. However, the proposed DCCB can interrupt a fault current of 30 kA when using the SCLM, which can limit a 30-kA fault current to approximately 3.5 kA within 2.5 ms. The arcing time of the IM was also significantly reduced as a result of the greatly reduced interrupting current. The effects of the IM parameters, including the commutation capacitance C 2 , the commutation inductance L 2 , the arc power loss coefficient N, and the arc time constant θ on the arcing time were analyzed. The arcing time can be reduced by increasing C 2 and N and reducing L 2 and θ.

Study of On-Line Detection of Voltage Transient Disturbance Based on DSP and Wavelet

In this paper, a set of voltage disturbance detection device based on DSP2812 was designed and a method of transient voltage disturbance detection based on DSP and Wavelet Transform was studied. The device collects electrical signal through a Hall sensor and the parallel A/D converter and regards TMS320F2812, a kind of high-performance digital signal processor (DSP), as a core data processing unit. Discrete Wavelet Transform (DWT) algorithm on DSP board was carried out to detect transient voltage disturbance. Software modules including the main program module, A/D module, interrupt module, communication module and so on was designed. The DWT algorithm on DSP board which could detect transient voltage disturbance on line was carried out based on the strong operation ability of DSP and the high effectiveness of DWT algorithm. This device can simultaneously realize power acquisition and voltage disturbance analysis in real-time. Contrast tests show that the device is of high-precision, of high-data-processing-speed and has a capability of voltage disturbance detecting in real-time.

Move-it: a paperclip-shaped sensing and actuating system for sticky notes

We developed a paperclip-shaped motion-actuating system, named “Move-it”. With this system, users can add motions to sticky notes just by clipping it. This system is constructed by using clip-shaped devices that have sensors and actuators. The recognition system uses photo interrupter module as sensor. Each clip device can recognize which note it has been attached to by calculating how much infrared light is being reflected by the grayscale image printed on the flip side of each note. The actuation system is made of a coil-shaped shape memory alloy combined with a polyolefin sheet that is embedded to the clip device, and can provide a sufficient motion for actuating the note. By writing for example, “meeting 16:00” on the sticky note using a digital pen and our device, the user can get physical reminder without any complex setting. This paper presents the design and evaluation of the recognition and actuation system of our clip-shaped device.

Properties of Occlusional Devices in Extended Time–Frequency Analysis of Post-Interrupter Respiratory Signals

The usefulness of popular occlusional heads to extended, time-frequency analysis of post-interrupter respiratory data was tested in this study. A portable mobile interrupter module, designed to acquire (also in telemedical system) raw signals of mouth pressure ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Q</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ao</sub> ) and airflow ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ao</sub> ), enabled flexible valve operation during normal breathing and flow induced by the airflow generator. The potential for algorithmic development of data processing procedures and hardware limitations of the shutter-type valve by Jaeger and Micro Medical is depicted here. The power spectrum density of <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">P</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">ao</sub> and input interrupter impedance ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Z</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">int</sub> ), calculated by the Micro Medical interrupter, were sensitive indices of respiratory mechanics measurement, but problematic natural oscillations and leakage during valve closing reduced the clinical relevance of the assessments. These hardware specifications represent prerequisites for prospective research in a sensing technology domain on an optimal valve-transducer unit design.

Wearable Interrupter Module for Home-Based Applications in a Telemedical System Dedicated to Respiratory Mechanics Measurements

The mobile interrupter module, dedicated to the enhanced interrupter (EIT) measurement of respiratory mechanics in a home environment and capable of cooperation with a telemedical system, is presented. Characterized by noninvasiveness and minimal requirements regarding patient cooperation, the EIT algorithm is especially suitable for newborns, preschool children, and patients suffering from respiratory muscle impairment. Furthermore, this device enables access to raw data--without initial preprocessing--in a fully flexible measurement protocol (which is not available in any commercial apparatus), and the EIT procedure improves insight (the number and precision of assessed parameters) into the physiological system with respect to the classical occlusive methods.

Use of one‐dimensional photodiode arrays to detect string vibratiom

A device has been developed to measure the x‐y amplitudes of vibration of a string and to facilitate waveform and frequency analysis of vibrations below about 500 Hz. This device can be used to detect amplitudes approximately ten times as great as is possible with photon‐coupled interrupter modules [C. E. Gough, J. Acoust. Soc. Am. 75, 1770–1776 (1984); R. J. Hanson, Phys. Teacher 25, 165–166 (1987)]. The device uses a pair of synchronized self‐scanning diode arrays mounted perpendicularly to each other such that each array responds to a shadow of the vibrating string. The output of each scan is two series of pulses. The pulses are converted to zeros and ones that are used to produce a pair of numbers which correspond to the absolute location in each coordinate component. The numbers are stored in the memory of the Apple II microcomputer in which the device is resident and are also routed to a pair of DAC's to regenerate the waveforms.

Voltage distribution characteristics of series connected SF/sub 6/ gas and vacuum interrupters immediately after a large AC current interruption

Transient voltage distribution characteristics of a hybrid interrupter module have been examined using an experimental model of a hybrid breaker. Tests were conducted to study the voltage distribution between the SF/sub 6/ gas and the vacuum interrupters immediately after a long current interruption. It is found that the voltage distribution is determined by the resistive impedances of respective interrupters during the post arc current flow and by the capacitive impedances of the interrupter's contact gaps after the post arc current diminishes. >

Simple low-cost optical position transducer

A low-cost, easily implemented optical position transducer with a range of about 10 mm and a precision of about 0.15 mm is described. The transducer uses a commercial photon-coupled interrupt module and a photographic film filter with a transmission which varies linearly with position. Simple and novel means of fabricating such filters and others of arbitrary characteristics by computer generation are described. The transducer has been successfully employed in an undergraduate mechanical resonance experiment.

High voltage vacuum circuit breakers

A new line of high voltage vacuum power circuit breakers is being developed for 121 kV and above and will use the new vacuum interrupter module presented in a companion paper <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . The first ratings in production will be 242 kV with interrupting capabilities of 40,000 amperes, followed by breakers rated 50,000 amperes; both of these will have continuous current ratings of 2000 and 3000 amperes. This paper departs from normal practice by submitting the new vacuum circuit breaker design concepts prior to manufacture. A future paper on the breaker testing program and test results will be submitted to the Institute. The breakers will be dead tank design and use SF <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</inf> gas only for insulation purposes. The interrupter contacts are to be mechanically driven by charged-spring type operating mechanisms. The breakers will be supplied for conventional outdoor switchyards and for high voltage gas-insulated station equipments.

An inexpensive mechanical stimulator incorporating a new optoelectronic device.

A displacement monitor for use with mechanical stimulators with range of 2.5 mm, ±5-percent linearity, l-μm resolution, and less than 25-μs rise time can be built inexpensively using a solid-state interrupter module. Operational amplifier circuits are given for loudspeaker driver and monitor electronics.

Versatile PDP-11 CAMAC Crate Controller for Nuclear Data Acquisition and Processing

A crate system controller has been designed with the aim to offer an economical and simple interface between CAMAC Dataway and Unibus of the PDP-11. This unit has the capability of transferring commands as well as 16 or 24 bit data words between the computer and a single module in programmed, increment to memory, add to memory and block transfer mode. An interrupt vector-generator module provides fast LAM handling. In line with the purpose to provide a versatile system the software for controlling the interface was kept simple and powerful.