FIELD: power engineering.
SUBSTANCE: proposed medium-voltage (3-10 kV) power mains having non-efficiently grounded neutral incorporates provision for reducing overvoltages by disconnecting motors with aid of vacuum switches. To this end it has three-phase voltage supply, vacuum switch, power cable, and overvoltage protective gear in the form of series-connected RC circuits inserted between phase leads at start of power cable (forming interphase delta connection).
EFFECT: enhanced reliability of motor overvoltage protective gear, enlarged functional capabilities, reduced mass and size.
1 cl, 5 dwg, 1 tbl
