SU917107A1 - Method and device for measuring signal instantaneous value - Google Patents

Description

A device for implementing a known method comprises a differentiating unit, the input of which is connected to the input of the device and one of the inputs of the adder, a key device and a pulse amplitude meter.

A disadvantage of the known method and device for its implementation is low measurement accuracy due to the fact that when summing the input signal and the pulse with a linearly rising front, the resulting signal gates during the time, since the rate of change of the instantaneous value of the signal is not constant, but also due to the fact that the voltage on the memory capacitor is kept for a "limited time," which requires fast-acting voltage meters.

The purpose of the invention is to improve the accuracy of measuring instantaneous values of the signal.

The goal is achieved by the fact that in the well-known method of measuring the instantaneous value of a signal by determining the magnitude of the converted signal obtained as a result of summing the measured and auxiliary signals, to form an additional signal, the measured signal is shifted by the level by such a constant The point is at zero level, and then the inverted signal is inverted.

A device for carrying out the method, comprising a differentiating unit, the input of which is connected to the input of the device and the first input of the adder, a key, a DC voltage meter and a synchronization unit, is additionally inserted in series with an integrator and an inverter, the signal input of the integrators the unit and the inverter output to the second input of the adder whose output is connected to a DC voltage meter, with a control key input and a reset input for the integrato and connected to the synchronization unit.

Figure 1 shows the functional diagram of the device; figure 2 - diagrams of the device

The essence of the method is as follows.

The measured signal is sshitshot on the vertical axis so that the point at which it is necessary to measure the instantaneous value of the signal coincides with the zero level. The received signal is inverted, after which it is summed up with the measured signal. As a result, a steady voltage is obtained, the level of which corresponds to the instantaneous value of the signal at the measuring point.

A device for carrying out the method comprises a differentiating unit 1, an adder 2, the inputs of which are connected to the input of the device, a serially connected switch 3, an integrator 4, an inverter 5 whose output is connected to the second input of the adder, a constant voltage meter 6 connected to the output of the adder and block 7 synchronization.

The device works as follows.

In the absence of a sync pulse (Fig. 2a, until t), the integrator is turned to the zero state, with key 3 open, and at the output of the inverter 5, the output signal is zero (Fig. 2c, until b). At the output of adder 2, up to the point in time td (Fig. 2d), the input signal (Fig. 26) repeats. At the time td, at which the signal value is to be measured, a sync pulse arrives (Fig. 2a, after ti) the closing key 3. The differentiated input signal from differentiating unit 1 is fed to the input of the integrator 4. From the time t, a signal is generated at the integrator output matching the input, but starting from the zero level, since the integrator is in the zero state before the arrival of the clock from the synchronization unit 7. This signal, after inversion by inverter 5, is shown in FIG. 2c. At the same time, the output signal of the adder 2 (from the time of B) is a constant value equal to the instantaneous value of the input signal at the time tA (Fig. 2d).

Thus, the proposed method allows one to accurately convert the instantaneous value of the signal to a constant voltage, the measurement of which does not require fast devices, since the resulting constant voltage can be kept at the output time required for the measurement.

Claims (3)

1. A method of measuring the instantaneous value of a signal by determining the magnitude of the converted signal obtained by summing the measured and auxiliary signals, characterized in that, in order to improve the measurement accuracy, to form an additional signal, the measured signal The signal is smtsayut on such a constant value so that the measured point coincides with the zero level, and then the mixed signal is inverted. . 2. A device containing a differentiating unit, the input of which is connected to the input of the device and the first input of the adder, a key, a constant voltage meter and a synchronization unit, that is, in order to improve accuracy measurements of the instantaneous values of the signal, the integrator and the inverter are additionally connected in series, with the signal input ing, the tegrator being connected via a key to the output of the differentiating unit, and the output of the inverter to the second input of the adder, the output of which is connected to a DC voltage meter, while the control input of the key and the reset input of the integrator are connected to the synchronization unit. Sources of information taken into account in the examination 1. Patent SZPA. 3611783, 0 cl. 328-151,1972. 2. Authors certificate of the USSR 458770, cl. G 01 R 19/04, 1975. 3. USSR author's certificate number 721757, cl. G 01 R 19/04, 1980. five Sroff fe / 8.1