SU905879A1 - Device for determining signal reading-out steps in time in stroboscopic measuring converters - Google Patents

Description

Start-up of a digital voltage generator, the output of an adjustable voltage generator connected to the input, the control input of which is connected to the third output of the control and processing unit, and the output to the adjustment input of the temporal loading of the test strobe converter associated with the signal input of the key element , the output and the first control input of which are connected to the trigger input of the analog-to-digital converter, and the second control input - to the fourth output of the control unit and processing.

The drawing shows a structural electrical circuit of the device.

The device consists of a sample sinusoidal voltage generator 1, a delay line 2, a test stroboscopic measuring converter 3, an analog-digital converter (ADC) 4, a key element 5, a control and processing unit b, an adjustable voltage amplifier 7, a digital voltage generator 8 of step voltage switch 9 and divider 10 number of signals.

The device works as follows.

The maximum value of the step voltage transmitted through the adjustable divider 7 voltage to the input of the time delay adjustment of the converter 3 is set so that the time shift (reading step) of the last of the strobe pulses relative to the initial zero level of the exemplary sinusoidal voltage slightly exceeds half the period of this voltage . Thus, the time scale of converter 3 is aligned with the half-period of sinusoidal voltage.

The device operates in the asynchronous mode of exchange of the converter 3 with the control block b and processing, in which the formation of the next voltage level by the generator 8 and the transition to the next readable point of the measured signal is performed after the block b is transmitted and processed in it Retinal value of the measured magnitude. This order of 6th exchange is provided by the key element 5c. the starting circuit of the A / D converter 4. A common strobe pulse transmitted through the key element 5 simultaneously with the start of the A / D converter 4 blocks this element before the release of the unlock signal from the control and processing unit 6. In the initial state of the device, the switch 9 provides for the transmission of the conversion end signals of the A / D converter 4 directly to the input of the generator 8. As the strobe pulses are generated, the A / D converter 4 is started, the current discrete value code is transmitted to the B block for analysis, and the next voltage level is generated by the end signal of the A / D converter 4 generator 8 and the corresponding strobe pulse, which after the release of the key element 5 repeats the read cycle of the next discrete value of the measured sinusoidal voltage stress. As the sinusoidal voltage is read, the discrete values approach the maximum level at the analog output of converter 3. With the receipt of the first discrete value after maximum, block b blocks the transfer of the ADC 4 signal through switch 9 and, at a fixed output voltage level of the generator 8, begins to change the transmission coefficient divider 7 voltage The divider's transmission coefficient is measured in such a way that, when the voltage of the generator 8 is fixed at a fixed number of steps, the corresponding pulse will shift in time relative to the initial sinusoidal voltage level to its quarter period, i.e. to its amplitude value. The control process is monitored in block b by readable discrete values of sinusoidal voltage as the strobes shift. The pitch and limits of the regulation of the divider transfer ratio are chosen in accordance with the voltage level of the generator 8. To obtain the maximum discrete value, the block b stops regulating the voltage divider 7 and thereby fixing its transmission coefficient and, therefore, the maximum value of the step voltage supplied to an input for adjusting the time delay of the transducer 3. In block B, the maximum value of U, the converted sinusoidal voltage, is memorized. Further, when the voltage divider 7 is set during the adjustment process, the reading cycle of the entire half-period of the sinusoidal voltage is repeated. From the obtained discrete values Ui, and in accordance with the inverse trigonometric function 1, describing the change in the sinusoidal voltage, block b calculates the time step tV for each U by the formula

ti arccos / 2 / rf,

where f is the frequency of an exemplary sius 5 of the normal voltage. In order to reduce

Claims (1)

Claim A device for determining the time steps for reading in stroboscopic measuring transducers, containing an exemplary sinusoidal voltage generator, connected to the input of the delay line by the output and the start input of the tested stroboscopic converter, the measuring input of which is connected to the output of the delay line, and the analog output to the signal input of an analog-to-digital converter, the first and second outputs of which are connected with the first and second inputs of the control and processing unit, the first output of connected to the reset input of a digital step voltage generator, characterized in that, in order to increase accuracy, it is equipped with a key element, an adjustable voltage divider, a switch and a signal number divider, the trigger input of which is connected to the first output of the analog-to-digital converter and the first input of the switch , the reset input is to the first output of the control and processing unit, and the output is to the third input of the switch, the second input of which is connected to the second output of the control and processing unit, and the output is connected to the input start-up of a digital generator of step voltage, the output connected: to the input of the adjustable voltage divider, the control input of which is connected to the third output of the control and processing unit, and the output to the input of the time delay adjustment of the tested stroboscopic converter, the output of the strobe pulses associated with the signal input of the key element, the output and the first control input of which is connected to the input of the start of an analog-digital converter, and the second control input is connected to the fourth output of the control unit and Processing.