FIELD: electrical engineering.
SUBSTANCE: invention relates to the electrical equipment, in particular to the electric power systems, and can be used to switch on, off and control the power transformer voltage at the rated level of the supply mains voltage and (or) current of the active-inductive load, as well as in case of supply mains voltage deviation in negative side and (or) active-inductive load current in positive direction. As a result of solving the set task, the level (limit) of voltage control is widened, as a result of which, in addition to the intermediate and minimum level of voltage control, a nominal level of voltage control will be introduced. In addition, the voltage control range between the supply mains voltage levels and (or) the active-inductive load current is also expanded, which will be divided into the upper and lower intermediate voltage control ranges, and also expands the possibility of performing the power transformer connection and disconnection operations, despite the supply mains voltage instability and (or) active-inductive load current. In the proposed method voltage control on the high side of the power transformer is provided at three voltage levels of the supply mains and/or active-inductive load currents: rated, intermediate and minimum. Proposed method also provides for division of intermediate level of voltage control into two ranges: upper and lower ones. During the electric power consumers voltage stabilization at supply mains (1) different voltages levels and (or) of active-inductive load (5) currents between the voltage control levels and ranges dead zone is introduced to change in conducting state of main (6), intermediate (10) and additional (9) thyristor switches, at which the voltage deviation on active-inductive loads (5) does not exceed 0.11% of the normally allowable voltage values both up and down from the voltage control degree of one or another level and voltage control range.
EFFECT: enlarging functional capabilities of the proposed device in order to preserve service life of electric equipment, improving quality of electric power and technical and economic parameters of power supply systems.
1 cl, 4 dwg
