SU1255758A2 - Apparatus for controlling a group of compressors - Google Patents

Description

The invention relates to the field of compressor control and is complementary to the author. St. No. 994809.

The purpose of the invention is to increase efficiency by increasing the accuracy of pressure level control.

FIG. 1 is a block diagram of the device; in fig. 2 - pressure derivative sign sensor.

The proposed device (Fig. 1) contains the first electrocontact manometer 1, the first 2, the second 3 and the third 4 schemes NOT: the first 5 and the second 6 schemes OR-NOT, the first 7, the second 8 and the third 9 schemes AND-NOT, the second 10, the third 11 and fourth 12 electrical contact gauges, trigger 13, counter 14, first 15 and second 16 delay circuits, pulse generator 17, reversible counter 18, generator triggers 19 and 20, counter inputs 21–21, and input 21 being counting, output 24 counters, inputs 25 and 26 of a reversible counter and its outputs 27- 32, as well as a sensor 33 of the sign of the derivative of pressure, four This scheme is NOT 34, the fourth scheme is NOT-35.

The sensor for the sign of the derivative of pressure (Fig. 2) contains an index arrow 36 of an electric contact pressure gauge (not shown), to the contact group 37 of which limiters 38 and 39 of the second arrow 40 are connected.

The device works as follows.

The flip-flop 13 is set to the zero state, and at the inputs 25 and 26 of the reversing counter 18, the single and zero signals appear, respectively.

Zero signals for switching on the compressor sets appear at the input 25 of the reversing counter 18 only when the monitored pressure parameters are reduced in comparison with the set values in the collector and at the end points of one or more main lines.

A zero signal appears at the output of the first IS 7 circuit, which, arriving at input 23, starts counter 14 (with one zero signal at input 23 or 22, counter 14 starts, and with single signals at input 23 and 22, the counter 14 is set to the zero position). In addition, the zero signal switches the trigger to one state. A single signal appears at the input 26 of the reversible counter, and at input 25, after a delay, a zero signal arrives at the reversible counter 18 to turn on the first compressor unit. Subsequently, with the arrival at the input 21 of the counter 14, the tenth pulse from the generator 17 a zero signal appears at the output 24 of the counter 14, which is fed through the fourth HE 34 to the second input of the fourth AND-NOT 35. Depending on the trend of the level change

The pressure in the system from the sensor 33 of the sign of the derivative of the pressure enters a single or zero signal.

If the pressure level decreases, the pointer arrow 36 (Fig. 2), moving down, moves the second arrow 40, whose position is fixed by the friction force on the axis, and is changed by the influence of the limiter 38, which is covered by electrical insulation preventing connection

 the second arrow 40 and the contact group 37 when moving the index arrow down. A single signal is generated, which from the output of the sensor 33 (Fig. 1) is fed to the first input of the fourth circuit

5 AND-NOT 35 and generates a single signal at the input 25. Then, at output 24 of counter 14, a single signal appears again, so at input 25 of the reversible counter, a second zero signal is generated, which is supplied to turn on the second signal

0 compressor installation. Similarly, other compressor plants are included.

When monitored system pressure parameters do not deviate from

5 values, the inputs 23 and 22 of the counter 14 receive single signals from the first circuits AND-NOT 7 and OR-NOT 5 and set it to the zero position.

Zero signals to shut down compressor installations appear at the input.

0 26 reversible counter only when monitored pressure parameters are increased compared with predetermined values at the collector or at the end points of all main lines. At the same time, at the output of the first scheme OR NOT 5 yo in

There is a zero signal which

to the input 22, it starts the counter 14. In addition, the zero signal switches the trigger 13 to the zero state.

With increasing pressure, the index

0, the arrow 36 (Fig. 2) moves upwards and moves the second arrow 40 to a new position by the action of the limiter 39 connected to the contact group 37. The second arrow 40 is connected to zero of the power supply, resulting in a sensor 33 output (Fig. 1) a zero signal is generated prohibiting the passage of pulses through the fourth AND-NO circuit 35.

A single signal appears at the input 25 of the reversing counter, and at input 26

d after the delay - zero signal, which is supplied to turn off one compressor unit. Subsequently, with the arrival at the 21st of the tenth pulse from the generator 17, a zero signal appears at the output 24 of the counter 14, which is fed to

5, the input of the third AND-NO circuit 9. In this case, a single signal is formed at the input 26. Then, at output 24 of counter 14, a single signal appears again, thus on

An input 26 of the reversing counter generates a second zero signal, which is supplied to turn off the next compressor unit. Similarly, other compressor installations are shut down.

Since the trend in the pressure level in the system is monitored, it is possible to increase the pulse frequency, which reduces the amplitude of self-oscillations during transients and improves the control accuracy.

39

36

FIG. Z

Claims (1)

DEVICE FOR MANAGING A GROUP OF COMPRESSORS by ed. St. No. 994809, characterized in that, in order to increase profitability by increasing the accuracy of regulating the pressure level, it further comprises a sign of the derivative of the pressure sign, as well as a fourth NOT circuit and an NAND circuit connected in series between the counter output and the second NAND circuit, moreover, the second input of the fourth circuit is NOT connected to the sign sensor of the derivative pressure. > SU „., 1255758