Efficient irrigation with ABB's AC drive improves farm productivity
Farmers irrigate their fields during periods of dry weather to ensure normal growth. As the irrigators are driven by the water flow, constant pressure is essential for even water distribution over the fields.
The irrigation system contains a frequency converter and eight parallel submersible pumps. The submersible pumps feed water to the irrigators, which are mounted on lightweight carriages. The carriages are first pulled across a field, then slowly dragged back by the water supply hoses rewinding onto large reels. As the reels are powered by flowing water, the pressure has to be constant to ensure an even water distribution.
Irrigation system
The speed of one pump motor is controlled by an AC drive, which also switches on the fixed-speed pumps as required. Another fixed-speed pump is started and the speed of the frequency converter driven pump is correspondingly reduced when the pressure in the pipeline falls below a preset limit. Conversely, the pumps are stopped sequentally when the pressure exceeds an upper limit.
Problems Solved
Pressure surges that stress the equipment mechanically
High labour cost
Uneven water distribution
Solution
Motors: 7x55 kW, 75 kW, 2500 to 3200 rpm, 380 V
Frequency Converter: 133 kVA, 380 V
Pressure regulation
Automatic pump control
Benefits
Even water distribution due to accurate flow control
Reduced energy consumption through optimum flow control
Lower maintenance costs as pressure schocks are eliminated