Showing papers on "Impulse generator published in 2002"

Impulse generator and method for perforating a cased wellbore

Abstract: An impulse generator ( 76 ) and method for using an impulse generator ( 76 ) to initiate a detonation in a shaped charge perforating apparatus ( 60 ) is disclosed. The shaped charge perforating apparatus ( 60 ) is adapted for use in a wellbore ( 62 ) and includes a plurality of shaped charges ( 86 ). A detonation cord ( 98 ) is operably coupled to each of the shaped charges ( 86 ). An initiator ( 78 ) is operable to detonate the detonation cord ( 98 ) upon receiving a triggering impulse. A Marx generator within the impulse generator ( 76 ) provides the triggering impulse to the initiator ( 78 ).

Impulse generator for profiling system

Abstract: An energy impulse generator for transferring an energy pulse to a surface. The generator exchanges messages with a computing means through a communication interface. The generator comprises a housing. The generator further comprises an impact assembly movably mounted within the housing between at least a resting position, a latched position and an impact position. In the impact position, the impact assembly transfers the energy pulse to the surface. The generator also includes an energy storage means attached to the impact assembly. In the latched position, the energy storage means is capable of releasing a specified amount of energy to the impact assembly such that upon release of the specified amount of energy the impact assembly moves from the latched position to the impact position then returns to the resting position. The computing means controls the release of the specified amount of energy to the impact assembly.

Radio transmitting apparatus, radio receiving apparatus, radio transmitting method, and radio receiving method

Abstract: A spread code sequence generator generates a spread code sequence with the frequency of a synthesizer, and then outputs the spread code sequence to a multiplier. The multiplier outputs a spread signal obtained by multiplying a data sequence by the spread code sequence to an impulse generator. The impulse generator generates an impulse signal of very fine impulses that corresponds to 0s/1s of the spread signal. The impulse signal is outputted to a band pass filter, where a predetermined range of the impulse signal is extracted. The output of the band pass filter is fed to a subtracter and a delay circuit. The delay circuit delays the delayed signal by a predetermined period. The delayed signal is outputted to the subtracter. The subtracter subtracts the delayed signal from the output of the band pass filter. A signal obtained by such subtraction processing is transmitted as a transmission signal via an antenna.

The generation of high electric field strength RF energy using Marx generators

Abstract: The Wave Erection Marx Generator is proving to be an excellent high voltage source for the direct generation of RF energy. Unfortunately, effectively radiating the impulse energy is challenging, both in efficiency and high voltage-holdoff capability. Successful efforts have been made to generate RF energy in both the Narrow Band and Ultra Wideband realm, with field strengths in excess of I kV/m at 100 m achieved. This paper briefly describes the impulse generator and explores its use for generating Narrow Band RF energy as well as Ultra Wideband energy. Experimental results will be presented.

Apparatus for generating electrical signals with ultra-wide band arbitrary waveforms

Abstract: Apparatus (22) for generating electrical signals with ultra-wide band arbitrary waveforms, which apparatus (22) comprises an optical impulse generator (24) for generating pulsed optical signals, splitter means (26) for splitting the optical signals into a plurality of optical signals in parallel signal paths, and combiner and optical detector means (30) for combining and detecting the signals in the parallel signal paths to generate the electrical signals with ultra-wide band arbitrary waveforms.

Calculable impulse voltage calibrator for calibration of impulse digitizers

Abstract: Design and construction of a calibrator for lightning and switching impulse voltage measuring instruments is presented. The operating voltage range is from 50 mV to 300 V. The estimated uncertainty for the peak value is 0.03% and for front time and time to half value less than 1%.

Unconditionally sequential approach to calculate the impulse strength of air for nonstandard impulse voltages

Abstract: The reliability of the power apparatus depends on the reliability of its insulation, which is tested with the standard lightning impulse voltages of wave shape 1.2/50 /spl mu/s. Often it is very difficult to adjust the impulse generator to get the standard wave shape within tolerance limits. While testing higher rating transformers, part of windings can get stressed with nonstandard voltages of both unidirectional and bidirectional oscillating waves. Hence it would be appropriate to test the power apparatus for the standard 1.2/50 /spl mu/s impulse voltages, and also to estimate the insulation strength for nonstandard impulse voltages. Disruptive effect method, which is a generalized method to estimate the breakdown voltage of insulation structures exposed to nonstandard lightning impulse voltages is an appropriate method to estimate the impulse strength for unidirectional nonstandard impulses. In this paper air as a basic insulating medium has been analyzed extensively for gap distances ranging from 1 mm to 5 mm for different electrode configuration from uniform to highly nonuniform field configuration. Unconditionally sequential approach, which caters to the bi-directionally oscillating voltages, has also been explained in this paper.

Investigation on lightning attachment manner by use of an experimental distribution line and a tree

Abstract: The authors have examined over a period the basic characteristics of discharge when an open wire fitted as an overhead ground wire is located near a tree, to clarify the attachment manner in which direct lightning hits power distribution lines which are in close proximity to trees. Previously, a focus was made on how lightning attachment emerges to the open wire or the tree. In this latest experiment, made at a testing yard using an experimental distribution line and a tall tree, a lightning impulse waveform and a switching impulse waveform were applied individually to a rod electrode. The different manners of attachment of sparkover to the distribution line and the tree were observed, along with manners of prebreakdown phenomena. This result coincided with the lightning attachment status previously achieved. This experiment revealed that the discharge characteristics shown in the previous study are valid.

An impulse generator simulation circuit

Abstract: This thesis describes the creation of a simulation circuit to match the output of a Marx type Impulse Generator. The goal was to estimate the stray capacitance and insert that capacitance into the simulation circuit to effectively produce an output similar to that of the generator. An actual three-stage impulse generator was used as the base. Several different levels of impulse voltage were tested, and the output waveforms were captured. Research was conducted to formulate the stray capacitance and identify the locations of these capacitances in the generator itself. The simulation circuit was then subjected to several iterations, adjusting the capacitance values to attain an output as close as possible to that of the actual generator. Conclusions of the research indicate that an effective simulation circuit can be created to give an output that is close to, but not exactly that of, the actual generator. In the research, several areas of error were identified in the actual generator that were not present in the simulation circuit. These areas are discussed in the thesis.

Magnetostrictive position measuring method and system with a start and stop impulse

Abstract: A magnetostrictive position measuring system is provided with a waveguide and which is allocated with a magnet movable along the waveguide. An impulse generator for generating an excitation pulse and a conductive wire for guiding the excitation pulse through the waveguide to the magnet are provided, whereby a torsion wave arises in the waveguide when the excitation pulse reaches the magnet. A reel for generating a reply pulse as a function of the torsion wave and a position calculation unit for ascertaining the position of the magnet as a function of the excitation pulse and the reply pulse are provided. A processor is provided in which a table is present in which a large number of positions and excitation pulse correction values are allocated to one another. The duration of the next excitation pulse is altered as a function of the position of the magnet ascertained and the associated excitation pulse correction value from the table.

Design and development of a high-voltage coaxial-hydrogen switch

Abstract: The high power microwave program at the Air Force Research Lab (AFRL) includes high power source development in narrow band and wideband technologies. The H-2 source is an existing wideband source that was developed at the AFRL. A recent AFRL requirement for a wideband impulse generator for use in materials testing has provided the need to update the old H-2 source. The source is composed of a dual resonant transformer that charges a short length of coaxial transmission line. This is then discharged into a following coaxial transmission line with a self-breaking hydrogen switch. The dual-resonant transformer is driven by a low-inductance, primary capacitor bank that operates through a self-break gas switch. The primary focus of this paper is the upgrade of the coaxial hydrogen output switch. The final design of this switch was developed through the use of extensive electrical and mechanical simulations.

Atrial cardiac pacemaker

Abstract: The invention concerns a pacemaker ( 52 ) designed for emitting stimulation impulses to an atrium ( 20 ) of a heart ( 22 ), with a connection for an atrial electrode wire ( 14 ) for emitting electrical impulses to the atrium ( 20 ), with an atrial stimulation impulse generator ( 24 ) that can be connected to the electrode wire ( 14 ) and is designed to generate atrial stimulation impulses that are to be emitted over an electrode wire, with a control unit ( 38 ) that is connected to the atrial stimulation impulse generator ( 24 ) and designed to trigger the stimulation impulse generator ( 24 ) in order to generate and emit atrial stimulation impulses, wherein the control unit ( 38 ) is designed in an AF-prevention mode that triggers the stimulation impulse generator ( 24 ) in order to generate a stimulation impulse sequence that is suitable for preventing atrial fibrillation (AF). It is characterized by an interval timer ( 34 ) that is connected to the control unit ( 32 ) and designed to turn the AF-prevention mode on and off according to the time of day and thereby activate or deactivate, in a time-controlled manner, the generation and emission of the stimulation impulse sequences preventing atrial fibrillation.

Method and device for diagnosing vision function disorders and repairing vision functions

Abstract: medicine; medical engineering. SUBSTANCE: method involves placing light protection glasses rim carrying photodiodes built in into the frontal panel. The photodiodes emit optical impulses of green, blue and red color. Diagnostic examination of vision functions is carried out by changing light impulse emission frequency from lower to higher values. Critical fusion frequency is determined in turn in each eye changing the fundamental three light impulse colors in succession. Functional state of the central zone of retina and optic nerve pathological changes are diagnosed by proving the following conditions. If critical fusion frequency in acting with red light falls to greater extent than in the cases of green light exposure and to greater extent when comparing to reference normal value, central retinal zone function disorder is to be diagnosed. If critical fusion frequency in acting with green light falls to greater extent than in the cases of red light exposure, optical nerve and vision tract disorders are to be diagnosed. Vision functions are repaired by applying pulsating color photostimulation method. Device has casing having impulse generator connected to two photodiodes fixed in light protection screen and to power supply source. Timer is mounted between the power supply source and impulse generator. EFFECT: high accuracy of diagnosis; enhanced effectiveness of treatment. 10 cl, 2 dwg

Unconditionally sequential approach to calculate the impulse

Abstract: The reliability of the power apparatus depends on the reliability of its insulation, which is tested with the standard lightning impulse voltages of wave shape 1.2/50~. Often it is very diffcult to adjust the impulse generator to get the standard wave shape within tolerance limits. While testing higher rating transformers, part of windings can get stressed with non-standard voltages of both unidirectional and bi- directional oscillating waves. Hence it would be appropriate to test the power apparatus for the standard 1.2/50 ps impulse voltages, and also to estimate the insulation strength for non- standard impulse voltages. Disruptive etTect method, which is a generalized method to estimate the breakdown voltage of insulation structures exposed to non-standard lightning impulse voltages is an appropriate method to estimate the impulse strength for uni-directional non-standard impulses. In this paper air as a basic insulating medium has been analyzed extensively for gap distances ranging from 1 mm to 5 mm for different electrode configuration from uniform to highly non-

High power subnanosecond genera tor for uwb radar

Abstract: Subn:mosecond pulse generator is one of the most importan t elements of ultrawideband (UWB) radar. Parameters of impulse generator influem;e to mdar perfonnance since it depends on radiation power and receiver sensi tivity. There are some ways to get high perfonnance factor of the UWB radar. It can be achieved as increasing of radiation power and multiply sampling data accumulation. In this paper we shall describe solid state. high power subnanosecond generator for portable UWB radar design.

Modeling of low voltage power network channel

Abstract: There is continued and growing interest in using low voltage power networks to realize "the last mile". We know that it is necessary and important for any communication system to study the channel model. The subject of this paper is the development of time-varying impulse response for a low voltage power network channel. Based on the theory of linear system, the authors analyze the propagation mode of electromagnetic waves in the power network and use the characteristics of signal multi-path propagation to deduce the time-varying impulse response of the low voltage power network channel. The impulse response is then discretized with the limitation resolution of the physical system. Finally, an example of physical system impulse response is given.

High-resolution rotation angle sensor for detecting the impulses of an impulse generator, fixed to a rotor, has a number of fixed sensor elements, with the total number of sensor elements equal to four or a multiple of four

Abstract: High-resolution rotation angle sensor for a rotor (20) that has an impulse generator fixed to it. The impulses of the generator are detected by a number of fixed sensors (S1-S16) that detect the generator signal pulse. Each impulse of the impulse generator has a defined length, (36) so that each impulse is detected by a number of sensors. The total number of sensors is four or a multiple of four.

Intelligent seismic profiling system

Abstract: An all-inclusive system for the non-intrusive physical analysis of a medium under a surface, and a display of the results thereof is described. The system detects the velocity of shear waves, analyses them and displays the results. The system comprises three units: a sensing assembly, an energy impulse generator and a user-computing interface.