SU220357A1 - METHOD FOR INCREASING THE CONSTANT TIME OF THE COMPENSATION DEVICE - Google Patents

Description

Methods are known for increasing the time constant of a compensation device by introducing into the measuring circuit of an integrating RC-chain, an integrating amplifier or an electrode of Schan integrators.

However, obtaining long time constants of the order of hundreds of seconds is limited by the leakage of capacitors, which, as a rule, are very unstable. The use of electromechanical integrators eliminates the use of standard automatic potentiometers as compensators, in which the signal processing time does not exceed 10 seconds.

In order to increase the dynamic accuracy of measurements, a method has been proposed for increasing the time constant of a compensating device, which consists in reducing the effective speed of movement of the reichord slider by periodically reversing the direction of rotation of the compensator motor.

FIG. I presents a block diagram of a device that allows reversing the direction of rotation of the engines.

A switch / with a frequency of 1 / T connects the circuits of the measured and reference signals to the converter 2, in which opposite-phase sawtooth pulses Ui are generated and whose amplitudes are proportional to the measured and reference signals, respectively. Such converters may be, for example, RC integrators. The frequency of the switch 1 is chosen significantly less than the frequency of the vibration transducer of the phase-sensitive amplifier 3.

The difference between the voltages taken from the constant resistance 4 and from the slider 5 of the DC compensator is applied to the input of the phase-sensitive amplifier 3.

The voltages occurring at points 6 and 7 relative to the ground are for the case (7 and em ar shown in Fig. 2. As can be seen from the diagrams, the compensator motor 8 will reverse with a period T due to a change in the phase of the voltage acting at the amplifier input. over time, the motor will rotate in the direction of decreasing the difference MJ between the amplitude values of the voltages operating at points 6 and 7, and during the time to - in the opposite direction.

The sum of the time intervals f and to is constant and equal to the reversal period T.

Depending on the difference in the amplitudes L / 7 of the sawtooth directions at points 6 and 7, the ratio between t and / g varies. With large values of the unbalance At / time t takes most of the period. As

a temporary increase of 4- At 1 4 g / 2. .

Thus, over a period, the effective time of moving the reichord engine in the direction of decreasing the unbalance will be equal to the difference, which means an increase in the instrument time constant. Here, the effective speed decreases as the imbalance decreases.

The modulation period T is chosen such that the width of the recording track of the automatic potentiometer does not exceed the specified measurement error.

Subject invention

A method for increasing the time constant of a compensating device based on the use of automatic compensators, in which it is compressed, and the value is worked out using an engine, characterized in that, in order to increase the dynamic accuracy of measurements, the compensator motor is periodically reversed, and the time of rotation of the engine in the direction of reducing the imbalance as the signal is processed, the signal is reduced, and the rotation time in the opposite direction is increased.

This signal

Measured Uu3M