SU942063A1 - Device for determining probabilities of maximum amplitudes of lightening discharges - Google Patents

Description

(5) A DEVICE FOR DETERMINING THE PROBABILITY DISTRIBUTION OF MAXIMUM AMPLITUDES The invention relates to specialized computer aids designed to measure the statistical characteristics of random processes. A device for mixing the amplitude distribution of pulse signals, comprising serially connected sensor signals, a differentiator, a pulse shaper, a pulse amplitude modulator and a multichannel amplitude analyzer, the pulse amplitude modulator input is connected to the output of the sensor 1, this device does not allow to determine the distribution of only the maximum amplitudes of the pulse signals. The closest in technical essence to the present invention is a device for determining the probability distribution of maximum amplitude pulse signals, which can be used to study disturbances of the electromagnetic field of the Earth due to lightning discharges (signals generated by lightning). The device contains serially connected signal sensor, trigger unit, delay unit, pulse shaper, pulse amplitude modulator and multichannel amplitude analyzer, as well as a main peak detector connected between the signal sensor and pulse amplitude modulator information input and a peak detector circuit connected between the output of the trigger unit and the input of the main peak detector S Such a device allows measuring the amplitude distribution of the first components of the signals, generating Mykh zipper E, wherein each component is composed of pulses predrazr impuls.a and the main discharge.

The predischarge pulses are bipolar pulses with little-varying amplitude, the magnitude of which is about an order of magnitude less than the amplitude of the corresponding main discharge pulse 2.

The main discharge pulses in the immediate vicinity of the lightning, as a rule, are unipolar, and in the case of bipolar pulses, the amplitudes of the quasi-half-periods differ significantly. The duration of one component, as a rule, does not exceed 5 ms. However, there are lightning discharges, in which the pre-discharge pulses significantly prevent the main discharge pulse. In this case, the component duration may exceed 5 ms, which, in turn, may lead to the loss of the maximum amplitude of the main-bit pulse, which is the greatest in the component. At the same time, the time interval during which the maximum amplitude occurs (the pulse duration at the output of the delay unit) cannot be increased, since this can lead to the selection of the maximum amplitude of the subsequent components. Thus, when using a known device, the probability distribution of the maximum amplitudes generated by lightning can be distorted.

The purpose of the invention is to improve the measurement accuracy.

The goal is achieved in that the device containing the first one-shot, the input of which is connected to the device's input, and the output is connected to the inputs of the second one-shot and the discharge unit of the peak detector, the output of which is connected to the control input of the peak detector the input amplitude impulse modulator, the control input of which is connected to the output of the first driver of the pulses, and the output connected to the input of the amplitude analyzer, entered the element And the element Ban, the second f rmirovatel pulses, the additional peak detector, an adder, and two restrictor, wherein the inputs of the first and second limiters are connected to the input device, and outputs coupled to the data inputs of the main

And additional peak detectors, respectively, whose outputs are connected to the corresponding inputs of the adder, the output of the adder is connected to the control input of the Ban element and the first, the input of the H element, the second input of which and the information input of the Ban element are connected to the output of the second one-oscillator, the output of the And element is connected to the input the first pulse shaper, and the output of the Inhibit element is connected to the input of the second pulse shaper, the output of which is connected to the control input of the first one-oscillator, the control input A supplementary peak detector is connected to the output circuit of the peak detector.

The drawing shows a block diagram of the proposed device.

A device for determining the probability distribution of the maximum amplitudes of the pulse signals includes an input 1 of the device, the first 2 and the second 3 one-vibrators, the element I, the first driver 5 pulses, the amplitude-pulse modulator 6, the amplitude analyzer 7 the second driver 8 pulses, the prohibition element 9, the adder 10, the first limiter 11, the peak detector 12, the second limiter 13, the additional peak detector 1, the 15th bit pattern of the peak detector, the output of the 8th bit of the first bit is connected to one of the inputs of the first single vibrator 2 first one-shot, the input of which is connected to the output of the prohibition element 9, one of the inputs of which is connected to the output of the second one-shot 3. And the second is combined with one of the inputs of the element And and connected to the output of the adder 10. Between the input 1 of the device and one of the inputs of the adder 10 are included serially connected first limiter 1 1 and peak detector 12. whose output is also connected to the information input of the amplitude-pulse modulator 6. Between the input 1 of the device and the other input of the adder 10 are connected serially connected a second stopper 13 and the additional peak detector 1A. In addition, the device contains a 15-bit peak detector circuit, the input of which is connected to the output of the first one-vibration 5 rator 2, and the output — to the control inputs of the peak detectors 12 and 14. Increasing the accuracy of measuring the probability distribution is maximum for the amplitudes of the first signal components, generated by lightning, is provided by eliminating the registration of the maximum amplitude of the pulses of the pre-discharge, which are bipolar pulses with low-variation amplitude instead of the maximum amplitude of the main pulse CBA yes. To do this, the peak detector 12 is supplied with a portion of the signal $ which corresponds to a positive polarity, and to an additional peak detector to a negative polarity. If by the end of the life of the first component (the end of the pulse at the output of the second one-oscillator 2) the magnitudes of the positive and negative voltages at the outputs of the peak detectors 12 and 1 differ slightly from each other in modulus, which corresponds to the pulses of the pre-discharge, then this signal is not recorded and the device returns to its original state without waiting for the end of the maximum time for the signal to exist (the end of the pulse and the output of the first one-oscillator 2. In the case of the selection process, The magnitude of the main discharge pulse, the magnitudes of the voltages at the outputs of the peak detectors 1 and 1 if by modulus are significantly different from, which results in the registration of such a signal. A pulse signal consisting of several components, each of which includes predischarge pulses and the main discharge pulse, from the input 1 of the device, arrives simultaneously to the inputs of the first oscillator 2 of the first limiter 11 and the second limiter 13. The output of the first limiter 11 passes only positive-polarity pulses, as well as Tel'nykh quasi zipoluperiody bipolar pulses that are input to peak detector 12. At the output of the second restrictor 13 oi- pass only pulses of negative polarity, and negative kvazipoluperiody bipolar pulses that are input to the additional peak detector. 63 When the signal exceeds the pre-selected threshold level, a single-square pulse appears at the output of the one-shot 2, the duration of which is set to the maximum duration of the multicomponent signal. In particular, when examining signals generated by lightning, this duration can be taken to be 1.5 s. The leading edge of a pulse from the output of the first one-shot 2 triggers the second one-shot three. At its output is a square pulse, the duration of which is equal to the first component of the studied multicomponent signal. When examining signals generated by lightning, this duration is chosen to be 5 ms. If by the end of this pulse the voltage at the output of the adder 10 (equal to the difference of the modules of the maximum amplitudes of the positive and negative polarity of the signal under study) exceeds the preselected threshold value, which indicates that the main component of the pulse of the first component is included in the analysis, the prohibition element 9 turns out to be closed, and the AND element is open. In this case, the back pulse from the output of the second one-shot 3 triggers the pulse shaper 5, which produces a normalizing pulse to the control input of the pulse-amplitude modulator 6. At the same time, the information input of the modulator 6 from the output of the peak detector 12 is supplied with a quasi-constant voltage the value of which is equal to the maximum amplitude of the signal at the input of the main peak detector. Thus, a pulse with normalized parameters appears at the output of modulator 6, the amplitude of which is equal to the maximum amplitude of the first component of the studied multicomponent signal. This pulse is recorded in the corresponding channel of the multichannel amplitude analyzer 7, depending on the amplitude. The back edge of the pulse from the output of the first single-shot 2 starts the node of the peak detector 15, which returns

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peak detectors 12 and C are in the initial state.

If by the end of the pulse at the output of the second one-shot 3, the voltage at the output of the adder 10 does not exceed the selected threshold value, which indicates that only the pre-discharge pulses are included in the analysis process, Element I 4 is closed, and prohibition element 9 is open. In this case, the signal at the output of the element And k is absent, the pulse shaper 5 is not started and, therefore, such a signal will not be recorded by the analyzer 7.

In addition, the back edge of the pulse from the output of the second one-shot 3, which passes through the prohibition element 9, triggers the form of the pulse 8 that returns the first one-shot to its initial state (the pulse at the output of this block ends. This in turn causes the node to start 15 bits of the peak detector, which returns to the initial state, peak detectors 12 and 1 4. Thus, the entire device is reset.

The device makes it possible to increase the measurement accuracy of the distribution of the maximum amplitudes of the first components of the signals generated by lightning, by eliminating the registration of the maximum amplitude of the predischarge pulses instead of the maximum amplitude of the main discharge pulse. The signals generated by lightning, in an implicit form, contain information about the distribution of charges and their spatial and temporal changes during the development of lightning. As a result, the probability distribution of the maximum amplitudes of the first components of these signals reflects the corresponding distribution for lightning currents, which is of considerable interest from the point of view of lightning protection.

Claims (2)

Invention Formula The device for determining the probability distribution is maximum The amplitudes of the lightning bits contain the first one-shot, the input of which is connected to the input of the device, and the output is connected to the inputs of the second one-shot and the node of the discharge of the peak detector, the output of which is connected to the control input of the peak detector, the output of which is connected to the information input of the amplitude-pulse the modulator, the control input of which is connected to the output of the first pulse driver, and the output is connected to the input of the amplitude analyzer, characterized in that, for the purpose of improving the accuracy, it contains Ment And, Prohibit, second pulse driver, additional peak detector, adder and two limiters, the inputs of the first and second terminators are connected to the device input, and the outputs are connected to the information inputs of the main and additional peak detectors, respectively, the outputs of which are connected to the corresponding inputs of the adder , the output to the adder is connected to the control input of the Ban element and the first input of the And element, the second input of which and the information input of the Ban element are connected to the output v cerned monostable, the output member and coupled to the first input of the pulse shaper, and prohibition element output is connected to the input of the second pulse shaper whose output is connected to the control input of the first monostable, the additional control input of the peak detector circuit connected to an output discharging pikoaogo detector. Sources of information taken into account in the examination 1, USSR Author's Certificate No. 356657, cl. G 06 G 7/32, 1972. 2. USSR author's certificate for application number 2901563 / 18-24, cl. G About G 7/52, 1979 (prototype).