METHOD FOR ADJUSTING ELECTRIC DRIVE OF BIT FEED REGULATOR Russian patent published in 1998 - IPC

FIELD: drilling machinery and equipment. SUBSTANCE: this can be used in drilling oil and gas well: according to method, after presetting thrust load on drill bit, it is converted into digital form in analog-digital converter of microprocessor unit. Bit feed speed is preset in microprocessor unit. After releasing of drilling pipe string and measuring of motor current, actual value of motor current is converted into digital form in analog-digital converter. Static motor current is determined in microprocessor unit according to algorithm given in description of invention. Recorded is static motor current in microprocessor unit, thus memorizing weight of drilling string before bit touches bottom-hole. Aforesaid operations are repeated at each drilling step in well through length of each pipe connected to drilling string. Then, electric drive of bit feed regulator is tested. After drill bit touches bottom-hole, motor current as measured by current sensor is converted into digital form in analog-digital converter. Determined in microprocessor unit is static motor current according to algorithm given in description of invention. Determined in microprocessor unit is thrust load on bit and detected is error in thrust load on bit. Error is processed according to algorithm given in description of invention, thus determining control signal for motor rotation speed. After measuring motor speed, its actual value is converted into digital form. Error of motor rotation speed is determined in microprocessor unit, its value is processed, thus finding assignment signal for current. Determined in microprocessor unit is error in motor current, it is processed, thus finding control signal for converter. Signal is directed to input-output port of microprocessor unit, it is converted into analog form in analog-digital converter and converted control signal is directed to converter which feeds motor. Electric drive is subjected to testing according to algorithm given in description of invention. EFFECT: higher efficiency. 1 cl, 8 dwg