Frequency control of asynchronous motor for an irrigation pump of machine irrigation systems
Abstract
The working state of freguency-operated asinchronous motor of irrigation pump in the closed system with feedback by velocity are considered. The system issue coefficient, provided a constancy of given value, loading coefficient of motor for voltage control pro rata control freguency are determined. Let us consider the static mode of operation of a frequency-controlled AM in a closed system with speed feedback. A decrease in the rotation speed in irrigation pumps to regulate their productivity is possible up to a certain minimum value, at which the pump head (H) becomes equal to the static head (H st ). The pump output (Q) then drops to zero. The value “k” has been determined, which ensures the constancy of the AM overload factor over the entire range of control frequency change in a closed-loop frequency control system with feedback on the engine speed.