SU1687897A1 - Method of automatic control of compressor unit - Google Patents

Abstract

This invention relates to the automatic control of centrifugal pumps and compressors and allows for increased reliability of the compressor unit. The voltage of the power supply network of the sensor 5, the total stator current of the synchronous motor 13, the sensor 6 consumed by the synchronous electric motor with the help of the sensor 7 is measured, the allowable value of the reactive power produced by the electric motor 13 is converted into the driving current signal and the level of this the signal is limited to the current value of the excitation current of the motor 13. 2 Il.

Description

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This invention relates to the automatic control of centrifugal pumps and compressors driven by a synchronous motor.

The purpose of the invention is increased reliability of control of a compressor unit.

Figure 1 shows a diagram of a device for implementing the proposed method; figure 2 - the algorithm of the computing device.

A device for implementing the method contains a throttle valve 1 in the bypass (, - line, sensor 2, pressure in the suction line, sensor 3) pressure in the discharge line, computing device L, sensor 5 of the power supply voltage, sensor 6 of the full current statort, sensor 7 active power, computing device 8, program block 9, adder 10, field current controller 11, sensor 12 of the current of the synchronous motor 13, sensor 14 of the reactive power of the supply network, throttle valve 15 in the suction line sensor 16 and of the occurrence of the subsequent aggregate, the turbocharger 17, the sampler 18 of the reactive power of the supply network, the sensor 19 of the reactive power of the supply network,

Throttle valves 1 and 15 dz are standard devices (ki 2, 3 h 16 pressure, voltage sensor 5, stator current datac 6, actuating power sensor 7, excitation current sensor 12, synchronous motor 13, reactive power sensor 14 and turbocharger 17

Microcomputers can be used as computing devices 4 and 8, Block 9 can be made in the form of a diode piecewise linear functional converter, and adder 10 can be based on an operational amplifier with an inverting input.

The proposed method is implemented as follows.

Sensors 2 and 3 measure the pressure in the suction line and the discharge line, respectively, and transmit their signals to the computing device 4. to the descents of the co-. The signal from CPG-IKR 12, 14, 19 and 16 also arrives. Install device-4 and, through sensor 12, deliver to inverting-A, the input of adder 10, the current of the electric motor 13 is energized so as to obtain the leading power factor to compensate for power, consuming asynchronous electric motors, switching on. /. eG /, ge mains, as well as poader + icier two-line in the suction line of the turbocharger 17 such that the gas supply is equal to the specified process regulations when the throttle valve 1 is closed in the bypass linky.

The device 8 according to the algorithm (see Fig. 2) carries out information input from the DETCHIKOR and the setting device 18. Then, the permissible reactive power Rp generated by the synchronous electric motor is computed.

RP V (Uic Iic) 2-Nf,

where Rp is the calculated reactive power;

bic is the power supply voltage;

lie gok the stator of a synchronous motor;

NI - power consumed by a synchronous electric motor.

A comparison is then made of the calculated Rp value with the maximum permissible value of Vosmax generated reactive power, determined by a specific type of synchronous motor 13 If Rp is Maxmax, the value Rp RCOM.-KC IF Rp - RcDMarc is assigned to the favorable value. TO

RW Rp. From devices 8 PBy comes to

the input of block 9, where it is converted into a signal proportional to the excitation current, the real dependence of the reactive power on the excitation current, and then transmitted to the non-inverting input of the adder 10, where

compared with the current value of the excitation current set by the device 4. At the output of the adder 10, a discrepancy signal is generated, which is fed to the input of the reamer 11, Regulator 11 depending on the sign of the discrepancy signal coming from the adder 10, reduces or increases the excitation current of the electric motor 13, maintaining its value at the level of the output signal of block 9.

Gas flow through the turbocharger 17 is stabilized by device 4, as shown in meters of sensors 3 and 16. If the gas pressure at the outlet of the compressor 17 is less than specified, device 4 issues a command

on the opening flap 1b. If the gas pressure at the outboard turbocharger 17 exceeds the set value, then device 4 will issue a command to open the valve 1 in the bypass line.

If given reactive power is RS

the mains supply is equal to zero, the device establishes HB 0 and the controller 11 sets the excitation current.

necessary for the operation of the electric motor 13 with cos p 1.

Claims (1)

Thus, the use of the method makes it possible to regulate the reactive power taking into account the load change of the compressor unit, and with the mismatch between the measured and set values of the reactive power of the supply network, more reactive power that the synchronous electric motor can generate in the power grid, taking into account its compensating capacity. In this case, the danger of the occurrence of pompage due to fluctuations in the stator current of the synchronous motor, as well as the emergency stop of the compressor unit due to overheating of the synchronous motor, i.e. The operational reliability of the control of the compressor unit is increased. The invention The method of automatic control of a compressor unit with an electric drive connected to the mains, by bypgsm gas flow from pumping to suction by pressure in the discharge line, measuring reactive power in the supply mains, removing it from the set point and adjusting the drive excitation of the drive according to the error signal, which is different. in order to increase reliability by preventing unstable operating modes of the compressor unit with a synchronous motor drive, in addition, when adjusting the excitation current, the voltage of the supply mains, the total stator current of the synchronous motor and the actuar power consumed by the synchronous electromotor are measured. determine the permissible sign of the reactive power produced by the synchronous motor, It is converted into a drive current drive signal, the level of which limits the current value of the drive current of a synchronous motor. (Start 3 Chgo wSod data Uic ,, 14