SU970244A2 - Device for digital measuring of ac voltage amplitude - Google Patents

Description

 The invention relates to a measurement technique and can be used in the development of devices for measuring the amplitude of an alternating voltage.

According to the main auth. 789814, a device containing a KCWparator is known, the first input of which is connected to the input of the extremity position detecting unit and the input signal bus, the second input of the comparator is connected to the digit-analogue output of the converter, the input of which is connected to the first output of the measuring torque code generator, the second output of which is connected From the first INPUT4 of the registration unit, the third output is connected to the first inputs of the measurement time deviation block, the start time detection block and the result block, the first input of the link code generator The second input is connected to the output of the cochaptor jf by the second input of the measurement time deviation block, and the second input is connected to the output of the start-up determination block, the second input of which is connected to the output of the measurement time deviation block and the second input of the result block whose output is connected to the second input of the block.

registration, the third input of the determination of the moment of launch is connected to; the trigger signal bus, and the fourth input - to the first output of the extremity position detecting unit, the second output of which is connected to the third input of the measurement time deviation block}.

The disadvantage of this device 1 is its low speed.

The purpose of the invention is to increase speed.

The goal is achieved by the fact that in a device for digital

15 measuring the amplitude of the alternating voltage, a block for determining the instant of switching off the sweep is entered, its first input is connected to the comparator output, the second input is connected to

20 by the third output of the measurement code generator, the third input is connected to the first output of the extremum block determining unit, the fourth input is connected to the device trigger signal bus, and the output is connected to the third input of the measurement timing code indicator.

Figure 1 shows a block diagram of a device for digital

30, the measurement of the amplitude of the alternating voltage in FIG. 2 is a timing diagram of the operation of the device. The device for digital measurement of the amplitude of the alternating voltage contains a comparator 1, the first input of which is connected to the input of the extreme position position detecting unit 2 and the input signal bus 3, the second input of the comparator 1 is connected to the output of the digital-analog converter 4, the input of which is connected to the first output of the imager 5, the moment code is measured, the second output of which is connected to the first input of the register-6 unit 6, the third output is connected to the first input of the measurement-off time unit 7, the start-up moment determination unit 8 and the ka 9 of the result, and unit 10 for determining the moment of deflection sweep, the first input of the imaging unit 5 is connected to the output of the comparator 1 and BTopbBv by the input of block 7, and the second input is connected to the output of block 8, the second input of which is connected to the output of block 7 and the second input of block 9, the output of which is connected to the second input of block 6,; the third input of block 8 is connected to the bus 11 of the trigger signal, and the fourth input to the first output of block 2, the second output of which is connected to the third input of block 7, the first input of block 10 is connected to the input of comparator 1 , second, the input is soin dinene with the third Exit shaper 5, a third input connected to the output peryomu unit 2, the fourth input is connected to the bus 11 and the output of block 10 is connected to the third input of the 5. An apparatus for measuring the digital amplitude of the alternating voltage works as follows. . On the 3 nocTSnaeT bus, the input signal being investigated, shown in FIG. 2C | positive half periods. A sawtooth voltage is applied to the second input of comparator 1 from the output of converter 4 of the digital analogue, which is generated from the trigger signal coming from block 8 (Fig. 2 (5) and shown in Fig. 2C1 by saw pieces. The value of sawtooth voltage at the output of converter 4 to any one the moment of time corresponds to the code from the output of the former 5, in block 2 for determining the position 31 of the strelm, pulses are formed (fig.2) at the moments of the input signal maxiMjpioB by comparing the points of intersection of the level of the input signal with the zero line Block 7 compares the position of these pulses with pulses from the output of comparator 1. The code from the output of block 7 f corresponds to the minimum difference in time between the pulses from the output of block 2 and the falling edges of the pulse from the output of comparator 5, arrives at the inputs of the blocks 8 and 9. In block B, a pulse is generated in FIG. 2cG) of the beginning of the formation of a measurement moment code produced in shaper 5 by a signal from block 8. Moreover, the position of the first pulse at the output of block 8 is determined by the arrival of a trigger pulse from bus 11. The formation of the second pulse is delayed by a signal (Fig. 27;) from the generator 5 until the code of the measurement moment; the driver 5 will not pass all possible values and the voltage at the output of converter 4 will not change from zero to maximum, which takes place at the maximum value of the input signal on bus 3 or until the output of block 10 does not come to signal. turning off the generation of the compensating signal, since the amplitude of the signal from the output of converter 4 exceeded the amplitude of the signal on bus 3. The second pulse will be generated after the end of the inhibitory signal (Fig. 21) and will be shifted from the beginning of the first pulse by an integer number of periods of the input signal and by corresponding to the minimum time difference between the pulses from the input of block 2 and the falling edge of the pulses from the output of the comparator 1. The second pulse from block 8 causes the code at the output of the former 5 to pass through a series of its own From the beginning to a certain value, the amplitude value of the input signal is superior to a negligible value. At the output of the transducer 4, in Vits, a sawtooth voltage, and at the output of the shaper 5, it prohibits a signal (Fig. 21). In block 7, the minimized time difference between the signals from block 2 and comparator 1 is again determined. In block 9, the result is determined if this minimum difference of acceptable value has reached. If not, then in block 8 the next additional shifted pulse is formed and the process repeats. If the minimum difference has reached a value, this indicates that the falling edge of the signal from the output of comparator 1 is at the maximum point of the input signal under study. At this moment, the signal of measurement moment is recorded by the signal from block 9 to block 6. This code corresponds to the amplitude value of the input signal under study. Thus, the introduction of block 10 provides for the cessation of the formation of a sawtooth voltage, as soon as it exceeds the value of the input signal, and, therefore, allows to significantly increase the speed of the device,

Claims (1)

Invention Formula A device for digital measurement of the amplitude of the alternating voltage according to the auth.St. 789814, characterized in that, in order to improve speed, a torque deactivation unit has been inserted into it, the first input is connected to the output of the xparator, the second input is connected to the third output of the measurement code generator, the third input is connected to the first output of the extremum position detection unit The fourth input is connected to the start-up signal bus of the device, and the output is connected to the third input of the measurement code generator. Sources of information taken into account in examination 1 ,. USSR Author's Certificate 789814, cl., G 01 R 19/04, 23.02.79. J .. F 9 at with f)