SU1359493A1 - Method of controlling compressor capacity - Google Patents

Abstract

The invention allows for improved economics by reducing power consumption. The performance control is carried out by changing the / CONDITION of the frequency of rotation of the electric drive. If it is necessary to reduce the performance, signals from pressure sensors 13 and 14 and gas flow at the outlet of the compressor go to multiplication unit 15, the output of which generates a signal proportional to the compressor hydraulic power. At the outputs of the functional converters 17 and 19, signals proportional to the powers P, and P, respectively, consumed by the electric drive 2 with throttling control depending on the rotational speed. The signals, proportional to: annee and Pn, are fed to the comparator 20, d -, i -J where they are compared. Based on the comparison results, an adjustment mode with a lower power consumption is selected. 1 il. G “Ezshee Targets food pit con tactor

Description

ten

1. 1359493

This invention relates to compressor control.

The aim of the invention is to increase efficiency by reducing power consumption.

The drawing shows the block diagram of the device that implements the proposed method.

The device for controlling the performance of compressor 1 with electric drive 2, equipped with frequency converter 3, contains contactors 4, 5 and 6, synchronization unit 7, converter current sensor 8, nonlinear unit 9 with dead zone and limiting, throttle control unit 10, model 11 amperes -second characteristic of the converter, logic unit 12, as well as the sensor 13 of the gas pressure at the compressor outlet, the sensor 14 of the gas flow at the compressor outlet, block 15 multiplication, - rotation frequency

compressor rotor. The signals from the outputs of block 15 and the first functional converter 16 are fed to the second functional converter, at the output of which a signal is generated that is proportional to the power P consumed

motorized 2 throttling:

one

under regulation

I i

P

0.97

15

20

From the output of the third functional converter 18, the signal goes to the rotational frequency fixing unit 25 and the rectifier and inverter control units 26 and 27 of the frequency converter 3, providing the required rotational speed of the compressor rotor.

In addition, the signal from the output of the third functional converter goes to the fourth functional, second, third and fourth functional converter 19, to the output converters 16-19, comparator 20, relay 21 with contacts 22, 23 and 24 V the power supply circuits of the contactors, as well as the rotational frequency fixing unit 25, the rectifier control unit 26 and the investor control unit 27. In addition, the drawing shows the coils 28, 29 and 30. contactors 4, 5 and 6.o.

The method is implemented as follows.

When the electric drive 2 of compressor 1 is operated from the mains and the need to reduce performance, the signals of the pressure sensors 13 and 14 and the gas flow rate at the compressor output go to the multiplier 15, the output of which produces a signal proportional to the hydraulic power of the compressor N. At the same time, the signal 14 of the sensor 14 gas flow is fed to the inputs of the first and third functional converters 16 and 18, the outputs of which form signals proportional to n aQ + + bQ + c.

40

de which a signal is formed that is proportional to P - power,

L emoi from the network depending on the frequency of rotation

30P K l),

where K is a coefficient.

Signals proportional to the powers P and P are fed to comparator 20, where they are compared. At Р Р

35, the relay 21 is activated, closes the contacts 22, 23 in the power supply circuits of the coils 28, 29 of the contactors 4, 5, and opens the contact 24 in the power supply circuit of the coil 30 of the contactor 6, resulting in a further decrease in performance by changing the frequency of rotation of the electric drive by acting on the converter 3 frequencies with current and time control

45 work carried out using a current sensor 8, a non-linear unit 9, a model, 11 amp-second characteristics of the converter and a logic unit 12,

50 If it is necessary to increase productivity, the regulation is carried out in the reverse order of what has been stated, i.e., with small values of productivity, regulation of the axis

d -Q 2H

dZQ2 4H

f Q + h N

Q

a, b, c, d, h5H

n

gas consumption at the outlet of the compressor;

coefficients - compressor efficiency;

j - rotation frequency

compressor rotor. The signals from the outputs of block 15 and the first functional converter 16 are fed to the second functional converter, at the output of which a signal is generated that is proportional to the power P consumed

motorized 2 throttling:

one

under regulation

I i

P

0.97

From the output of the third functional converter 18, the signal goes to the rotational frequency fixing unit 25 and the rectifier and inverter control units 26 and 27 of the frequency converter 3, providing the required rotational speed of the compressor rotor.

In addition, from the output of the third function converter sig0

de which a signal is formed that is proportional to P - power,

L emoi from the network depending on the frequency of rotation

0P K l), i

where K is a coefficient.

Signals proportional to the powers P and P are fed to comparator 20, where they are compared. At Р Р

5, relay 21 is activated, closes contacts 22, 23 in the power supply circuits of coils 28, 29 of contactors 4, 5, and opens contact 24 in the power supply circuit of coil 30 of contactor 6, resulting in a further decrease in performance by changing the frequency of rotation of the electric drive by acting on the converter 3 frequencies with current and time control

5 of the work carried out by the current sensor 8, the nonlinear block 9, model, 11 amp-second characteristics of the converter and the logic block 12,

0 If it is necessary to increase productivity, regulation is carried out in the reverse order of what was stated, i.e., at small values of productivity, regulation is actually implemented by varying the rotation frequency, since P, - P, and then, as performance increases, when Pj 7 / P, the signal at the output of the comparator 20 is reduced, the relay is 21 times.

closes contacts 22 and 23, closes by changing the position of the throttle contact 24 and turns off the electrical input of the valve installed at the inlet to the mains, mines the inverter compressor, which differs in frequency, with the aim of a higher economical Lenin throttle valve comes in by means of reducing the flow rate, the control signal, realizing that electric power, additionally measured by the performance control, the flow rate and pressure of the gas at the output by changing the position of the throttle valve, The power consumed by the electric drive when regulating the invention formula by change and the power consumed by the electric drive when adjusting the method of controlling the production by changing the position of the throttle of the compressor with an electric 15 gate valve is compared half way equipped with a transducer of power and re-frequency, by changing the frequency, by comparison, choose the pcjKiiM of the rotation of the drive to control frequency converter or consumption.

Claims (1)

Claim A method for controlling the performance of a compressor with an electric drive equipped with a frequency converter, by changing the frequency of rotation of the electric drive by acting on the frequency converter or by changing the position of the throttle valve installed at the compressor inlet, characterized in that, in order to increase economic efficiency by reducing energy consumption, the gas flow rate and pressure at the compressor outlet are additionally measured, the power consumed by the electric drive when controlling a change, and the power consumed by the electric drive when controlling a change in the position of the throttle damper, are additionally measured, compare the obtained values of the capacities and according to the results of the comparison, choose a control mode with a lower power consumption.