METHOD FOR AUTOMATIC START-UP AND BRAKING OF ELECTRIC DRIVES OF INDEPENDENT ELECTRIC POWER SOURCE OF COMPARABLE POWER Russian patent published in 2016 - IPC H02P1/26 H02P3/24 

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and can be used for dynamic braking of three-phase asynchronous motor and for starting from an autonomous source of electric energy of comparable power. Method for automatic start-up and braking of electric drives from an autonomous electric power source of comparable power comprises, when a signal reaches a radio communication device, applying voltage to autonomous power source of comparable power and programmable logic controller executes series connection of magnetic starters and connects the unit B to a capacitor installation and depending on information coming from a wireless current and voltage sensor, load sensor on pumping unit rod, programmable logic controller performs control of control unit of capacitor installation, in its turn includes required number of controlled capacitors in power supply circuit. At moment when values of starting current of motor stator become equal to 1.4-1.6 of nominal value, programmable logic controller executes smooth switching off of parallel units of controlled capacitors, and then magnetic starter. At considerable loads, overloads, which is fixed by load sensor on pumping unit rod, or reducing supply voltage, programmable logic controller recognises operating modes of pumping unit and based on parameters and obtained data performs corresponding series connection of magnetic starter and parallel units of controlled capacitors of unit B by feeding control action to control unit of capacitor installation and provides charge of units of controlled capacitors with via braking energy conversion, during downward movement of pumping unit rod, into electrical energy. Method for automatic start-up and braking of electric drives of autonomous electric power source of comparable power ensures operation in alternative energy and renewable energy sources, which power production remote wells, which reduces cost, since there is no need to build additional power supply infrastructure for remote facilities, such as well as machine-rockers, submersible electric motors, screw pumps and chain drives and other gas production facilities.

EFFECT: technical result is decrease of power ratio of autonomous source of three-phase alternating current with power of launched therefrom by direct start-up three-phase induction squirrel-cage motor up to 1,5 -2,0, which provides: reduction of power of drive motor and generator; reduced weight and dimensions of power source; possibility of using three-phase short-circuited; possibility of excluding starting rheostat.

2 cl, 2 dwg