SU977565A1 - Method for controlling water supply at canal portion - Google Patents

Description

The invention relates to agriculture and can be used in irrigation systems to control the level or flow of water in a section of a canal.

The known method of water distribution, or on the irrigation canal site, includes simultaneous measurement of water levels at the beginning and end of the plot, determining their resulting value compared with the level at a given point of the plot, and applying these resulting readings to change the flow of water flow to the beginning of the plot in order to maintain a constant (given) level at a given point 1.

The disadvantage of this method is the low accuracy of maintaining a given level or flow of water at the end of a section when changing the level or flow of water at the beginning of a section, which leads to a large reserve of water at the end of the section for the duration of the reconstruction of the section

and to increase the cost of the channel.

Also known is the level control system in the channel section, in

Which level control is carried out by measuring the levels at the beginning

and the end of the section and the comparison of the levels with the specified ones, the regulation of the levels is carried out by the control system by means of the regulators (blocking structures) at the beginning and end of the section 2.

The disadvantage of such a water supply control is the difficulty of level control and the insufficient reduction of the reserve capacity of the channel.

The purpose of the invention is to simplify the control and reduce the reserve volume of the channel by increasing the level control accuracy at the end of the section.

The goal is achieved by adjusting the lateral water supply for differences in sensor readings that limit the current, then measuring the level at the end of the section, then compensating for the sensor error signal at the beginning of the section, and further adjusting the lateral water supply at the end of the plot, where the start of regulation of the lateral water supply is made taking into account the time of deceleration from the beginning of the site and from the lateral water supply controller to the end of the site. The drawing shows the implementation of the method for adjusting the level in the channel section. The scheme includes a plot of irrigation system 1 with barrier with weapon 2, for example, at the end of the plot (in general, there may be no blocking at the site) and adjustable lateral water supply 3 located above structure 2. At the beginning of section 1, above the zone Neither the water flow of the station and the lateral regulated water supply 3 has a level 4 sensor, and in front of the partition 2 - a level 5 sensor (it is assumed that there is a backwater curve at the end of the section). For a section with a blocking structure and a downstream adjustable lateral water supply along the flow of water, the level or discharge at the end of the section is measured by not extending the area of the water flow of the section with regulated lateral water flow, and when the controlled lateral flow is located along the flow of water, the measurement The flow rate or level at the beginning of the section is not produced below the zone where the flow of the section is reduced to the flow rate of the regulated side water supply. An electric regulator 7 controls the gate with an electric drive of the burnout of a nonstop structure with adjustable side water supply 3. The circuit also contains one-shot 8, element 9, threshold element 1 delay element 11, element OR 12 compensation block 13, comparison elements 14 and 15, the keys 16 and 17, and the sum of the torus 18 Method are implemented as follows. When the level (flow) of water at the beginning of section 1 changes, the signal of sensor 4 changes relative to the value of the output signal of the compensation unit 13 that is set at the beginning, and when the deadline of the comparison element 14 of the comparison element 14 is exceeded, the signal of the direction More or Less appears. . If the travel time from sensor 4 to sensor 5 is equal to (or less) the travel time from blocking structure to sensor 5, the delay element il is set to a delay time equal to zero, and then key 16 is opened through the element OR 12. If the travel time from sensor 4 to sensor 5 is longer than the indicated time, the delay element 11 is adjusted to the delay time required for these running times to be compared, after which the key 16 is opened through the OR 12 element. The signal is larger or smaller through the public keys 16 and 17 t to one of the inputs of the adder 18, to the other input of which a signal is output from the element 15 of the comparison. If the change in the value of the signal from the output of sensor 5 relative to the set value of the level at the end of the section exceeds the dead zone of the reference element 15, then the output of the latter appears to be More or Less, and if it does not exceed the dead zone, then the output signal of the comparison element is zero. Suppose the output of a reference element is zero. Then the direction signal More or Less from the comparison element 15 from the output of the adder 18 is fed to the input of the automatic controller 7. From the output, the latter receives a command to raise or lower the electric valve of the partition 6 to compensate for the change in the flow rate of the regulated lateral water supply 3 at the beginning of section 1 in order to maintain a predetermined level at the end of section 1 (at the installation point of sensor 5). At the end of the control signal from the output of the automatic controller 7 at the output of the one-shot 8, the output signal appears for the time required for the block 13 to compensate for the zero output signal of the comparison element 14. This happens as follows. The generated signal More or Less from the output of element 1-4 through the key 16 enters the input of the threshold element 10, which allows the output signal to one of the inputs of the element And 9. When a signal from the output of the one-vibrator 8 appears at the other input of the element And 9 the output of the latter is reset to the initial state by the delay element 11, the key 16 is maintained through the OR element 12, the key 17 is closed, and the zero output signal of the comparison element 14 is allowed by the compensation block 13. At the end of the output signal of the one-shot 8, the output signal disappears from the output of the AND 9 element, which leads to the opening of the key 17, the disconnection of the resolving signal to the installation, the zero output signal of the comparison element 14 by the compensation block 13 and the end of the reset of the delay element 11. . Until the end of the output signal of the one-shot 9, the above-mentioned conversions from the output of the AND 9 element are possible, if the resolving output signal of the threshold elec-

Claims (1)

Claim A method of regulating water supply in a channel section, including measuring levels by sensors at the beginning and end of the section, comparing levels with predetermined levels and controlling the levels with a control system using partition walls, characterized in that, in order to simplify regulation and reduce the reserve volume of the channel by increasing the accuracy of level control at the end of the site, regulation is carried out by lateral water supply according to the differences in the readings of sensors that limit the site, after which the level is measured at portion, then compensate sensor signal mismatch in the beginning portion, and further regulate the water supply side sensor readings produced by the end portion, wherein the top side regulating water supply produce given the time lag from the beginning portion of the regulator and the water supply side to the end portion.