SU843868A1 - Sprinkling irrigation system - Google Patents

Description

(54) DROP IRRIGATION SYSTEM

one

This invention relates to agriculture.

A drip irrigation system 1 is known, comprising a pump connected in series with an electric drive, a control throttle, a filter, a main pipeline with distribution pipes with droppers connected to it.

The disadvantages of the system are the lack of automation of the irrigation process and significant energy losses when creating the required pressure in the line by throttling the water flow.

Also known is an automated sprinkler irrigation system comprising a pumping station, a discharge line with a pressure sensor connected to a software device, a compressor and irrigation pipes with sprinklers connected via control units containing a time relay, an actuator whose output is the first output of the control unit , and a three-membrane relay, the output of which is the second output of the control unit, while the time relay input, the power channel of the three-membrane relay and control avl 2

The input of the executive is the input of the control unit {2.

The disadvantages of the system are the impossibility of ensuring uniform supply

water at low flow rates and pressures, which degrades the quality of irrigation and energy loss during throttling of the main flow area by the executive body.

The aim of the invention is to improve the quality of irrigation by compensating for both abrupt and gradual changes in pressure in the pressure pipe and save irrigation water by powering the pump drive motor.

This is achieved by the fact that in a drip irrigation system containing a pump unit driven by an electric motor powered from an alternating current source, a pressure pipe with filter, sprinklers with droppers installed on them and a software device including a pressure sensor in the pressure pipe and successively connected units

assignment and comparison, the AC source is frequency adjustable and connected to the output of the software device, which additionally contains a frequency changing command generation unit and an integrator connected to the comparison unit, the integrator output connected to the second input of the frequency variation command generating unit.

FIG. 1 is a block diagram of a drip irrigation system; in fig. 2 shows the graphs of the drip irrigation system.

The drip irrigation system contains a motor 1 with a constant current, a pump unit 2, a filter 3, a pressure pipe 4, irrigation pipes 5 with droppers 6, a pressure sensor 7 mounted on the pressure pipe, the device 8, a comparison unit 9, an integrator U, a block And forming frequency measurement commands, an alternating current source 12, the frequency of which is varied so that the pressure in the pressure pipe is as specified.

FIG. 2a is a graph of changes in water flow; b - graph of changes in the resistance of the hydraulic network; B is a plot of the comparison block output signal; g is a plot of pressure developed by the pump unit; e is a graph of pressure in the pressure pipe; e is the time coordinate.

The system works as follows.

After connecting to the engine 1 a pump unit 2 and an AC power source 12 with a given initial frequency, corresponding to creating the required speed of the pump unit, and sequentially setting the pressure in the pressure pipe 4, the calculated number of irrigation pipelines 5 with droppers 6 is put into operation .

If at the time point i, as a result of connecting additional irrigation pipelines with droppers to the pressure pipeline, the flow rate increases (graph a), then due to the appearance of a small pressure change (graph e), the magnitude of the signal at the output of comparator 9 (graph c) changes. The frequency change command generation unit processes the signal change at the output of the comparison unit, issuing a command signal to change the frequency to the variable frequency source, as a result of which the rotation frequency of the pump 2 increases and the pressure reaches filter 3 (graph d), which compensates for the increased pressure drop across it. As a result of the perturbation testing, the pressure in the pressure pipe is set within the specified limits.

With a gradual increase in the hydraulic resistance of the network, for example filter 3, since tz, the integrator 10 accumulates small values of the pressure deviation

from a given value (graph c), and the signal at its output increases, as a result of which the rotation frequency of the pump increases accordingly, the pressure in front of the filter (graph d) increases. This compensates for the increasing pressure drop across the filter at nominal water flow. The pressure after the filter (schedule e) remains within the prescribed limits. Use pressure control

in the drip irrigation system, by varying the rotational speed of the pump, the desired output pressure range is obtained with a smooth control, ensuring equal flow through the drippers

and uniform irrigation of the area.

The use of the proposed device will improve the automation of the drip irrigation process, as well as provide the specified consumption of droppers without unproductive energy losses, which will save about 300 thousand kWh of electricity per year on a 500-hectare garden.

Claims (2)

1. USSR author's certificate No. 412345, cl. A 01G 25/02, 1970. 2. USSR author's certificate No. 612662, cl. And OIG 25/16, 1979 (prototype). U2.i tf tz