The issues of developing a methodology for calculating the specific rates of electrical energy consumption during frequency regulation of electric drives of pumping stations are considered. When calculating specific consumption rates, experimental studies were carried out at the Chirchik pumping station. When developing the methodology, technological, design parameters, water consumption, as well as the total capacity of pumping units based on frequency-controlled electric drives are taken into account. At the same time, the characteristics of the main parameters that must be taken into account when choosing variable frequency drives for pumping units are determined.

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 (Hst). 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.

The article analyzes the control of pumping aggregates by means of frequency converters. Information is provided on the structure of the operating principles of the frequency converter, the conditions of connection to the pumping aggregates. Experimental research has shown that the cost-effectiveness of resource savings is achieved through the smooth operation and smoothing of the dynamic modes of the system “frequency converter - asynchronous motor - centrifugal pump - pressure transmission line”.