Calculation methodology for determining the number of simultaneous self-starting pumping units

Abstract

The paper considers the methodology of calculating the number of self-starting pump units depending on the network voltage landing and the basic calculation dependencies of the process of selfstarting of electric motors supplied from three-phase three-winding transformer; the substitution scheme for one phase of the circuit is made. Technical solutions for upgrading pump units, which allow applying the selfstart mode at ameliorative pumping stations, are proposed.

Transformations of equations with approximation of characteristics of nonlinear elements by power polynomial

“…1, 2, 3), which are parts of certain electrical circuits. The material of ferromagnetic cores is assumed to be isotropic and the same for all three magnetic circuits, and the dependence of the induction on the magnetic field strength (magnetization curve) is unambiguous and symmetrical relative to the origin of coordinates [6][7][8]. As is known, such a magnetization curve can be approximated by a polynomial:…”

Application of numerical and graphical methods of analysis in nonlinear resistive circuits of electronic devices

“…Here the minus sign, taken before the radical, takes into account that under stress u=0 the current will also be zero [15][16][17][18]. On the basis of equation ( 3) with the use of a computer, a graph of the change in current as a function of time is calculated and built.…”

Efficient protection and control of electric drives using solid state circuits

“…Theoretical studies of the components of the proposed device, the following circuits were considered, shown in Figures 1 and 2. [15][16][17][18][19][20] Figure 1.a) shows a diode thyristor circuit, where a relay effect is revealed, with the help of which it is proposed to start and protect against under voltage in the control circuits of asynchronous motors. The explanation of the phenomenon of the relay effect can be carried out using the example of a diode-thyristor circuit, when the thyristor VТ is connected in series to the network through R н active resistance, and the control circuit is supplied with current from the network through the active resistance R and the diode VD (Fig.…”