SU1560810A1 - Method of controlling a pumping station - Google Patents

Abstract

The invention makes it possible to increase control efficiency by increasing the accuracy of pressure control by optimally selecting a control cross section. During the operation of the station, a control parameter, such as a static pressure, is determined at the beginning of the common section of the station’s discharge pipe. Based on the result of comparing this parameter with its set point, the need to change the number of operating pumps is predicted. In case of a positive forecast result, depending on the combination of operating pumps, a control section is determined either in the pressure lines of the pumps or in the general pressure pipe, characterized by a lower static pressure, and, consequently, a greater steep pressure characteristic. The pressure in this section is measured and used to determine the control parameter. In addition, the difference between the pressure values in the control section and at the pump inlet can be used as a control parameter. Also, the control accuracy can be improved by keeping the pumped liquid level constant.

Description

The invention relates to pump construction and can be used in automated control systems for pumping stations.

The purpose of the invention is to increase control efficiency by increasing the accuracy of pressure control through the optimal selection of a control cross section.

The drawing shows a diagram of an apparatus for carrying out the proposed method.

The control unit of the pumping station, which includes the pumps 1, contains a block of 2 pressure sensors installed in pre-selected

pressure pipe sections (both the common section and the pump pressure lines), pressure control unit 3 in the initial section of the common pressure pipeline, pump state control unit 4 (on-off), transient operation forecast unit 5, block 6 selection of the control section, block 7 for generating signals for switching on and off pumps 1, block 8 for controlling pumps (for this block, typical ones can be used; control cabinets for pump units based on relay or logic elements).

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The control method of the pump station is carried out as follows.

The output of block 2 displays information about the pressure at all test points, the output of block 3 shows the pressure at the initial section of the (common) pressure pipe of the pumping station, and the output of block 4 shows the status of pumps 1. The last signal can be represented in the type of information about the presence of a certain pressure at the outlet of the pump 1 or its absence, the current or power consumption of the pump 1 of a given value, etc. Unit 5 analyzes information1 about the connection of the CGs, determines the combination of operating nays and compares the control parameter corresponding to the pressure at the output of block 3 with the set value determined during nominal mode and stored in its memory. If the parameter is less than nominal, then the output of block 5 is a signal of transient mode 1 2, where 1 is the number of pumps currently running 1, 2 is the possible change in the number of pumps running 1. If the control parameter is larger than the nominal, then the output of block 5 is in summer transient prediction signal 1 - 0. unit 6 depending on the predicted transient section and selects an appropriate unit 7 transmits selection information to the control section and the corresponding reference parameter setting. Block 7 compares the control parameter with the setpoint for the selected section and if it has reached the setpoint level, a signal is generated to turn on the second order pump or turn off the operating pump.

The implementation of other transient modes of the pumping station is carried out in a similar way.

At the same time, blocks 5 and 7 are preliminarily laid down with the setpoint of the control parameter at the initial part of the common pressure pipe of the pumping station under nominal operating modes for each combination of pumps 1 and the setpoint for implementing transient operating modes of the pumping station determined by calculation or experiment. For various combinations of pa

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for boiling pumps 1, the position of the pressure pipe section in which greater pressure control accuracy will be achieved will be different and will be characterized by sections with lower static pressure values or higher flow rates,

In the case when the level of the latter is kept constant in the source of the pumped liquid, the amplitude values of possible non-technological pressure changes are reduced, which helps to reduce the required range of pressure changes in the control sections under transient operating conditions of the pump station. Consequently, a larger number of control sections can satisfy the required pressure range. This will reduce the number of control sections, and, consequently, the number of sensors.

The effect of the implementation of additional pressure control in the suction lines of operating pumps 1 directly at their inputs and using as a control parameter the pressure difference measured in the control section selected for the implementation of a given transient operating mode of the pump station and in the suction lines of the working pumps is similar to the effect obtained from maintaining the last constant level in the source of the pumped liquid, the decrease in the amplitude values etehnologicheskih changes in pressure is accomplished by eliminating the influence of the liquid level fluctuations. In addition, when this feature is implemented, the ranges of variation of the monitored parameter are increased by taking into account the pressure losses in the suction communications of pumps 1. This reduces the number of control sections required.

Claims (1)

Invention Formula G. A method of controlling a pump station, including the measurement of static pressure in a pressure line, determining a control parameter from it, comparing it with a set value, and changing the number of operating pumps depending on the deviation of the control parameter from the set value, in order to increase control efficiency by increasing the accuracy of pressure control due to the optimal choice of the control cross section, depending on the combination of operating pumps The control section in the pressure line, characterized by a lower static pressure value, is used to re-measure the pressure in the prescribed section, determine the subsequent values of the control parameter, and then repeat the measurement 810 rhenium until the permissible value of the mismatch between the control parameter and its specified value is reached. 2, Method pop, 1, characterized in that the static pressure value at the pump inlet is measured, it is subtracted from the static pressure value in the test section, and the difference obtained is used as a control parameter. 3, the Method according to PP. 1 or 2, about t l i-cha pumped liquid is kept constant. Editor Y. Sereda Compiled by K.Staloverov Tehred M.DidykKorrektor T.Malets Order 964 Circulation 494 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Production and publishing plant Patent, Uzhgorod, st. Gagarin, 101 Subscription