Patent ID: 8747074

Claim:
An oil pump control apparatus of a hybrid vehicle, comprising: an engine operated as a first power source, wherein the engine is configured to be turned on and off depending on a driving mode and condition; a motor that is operated as a second power source by a 3-phase AC current supplied from an inverter to transfer output torque to a transmission and function as a generator to retrieve a regeneration energy during deceleration; an engine clutch that connects and disconnects the engine with the motor; a first oil pump disposed in the transmission to be connected to the motor, the first oil pump operated by the motor when the engine is turned off in an electric vehicle (EV) or hybrid stop and go (HSG) mode, and is operated by the engine power transferred from the engine clutch in an hybrid electric vehicle (HEV) mode to form a line pressure; an electric oil pump configured to be operated when the engine is turned off in an EV or HSG mode to form a hydraulic pressure in the transmission and the engine clutch; and a hybrid controller that controls the electric oil pump according to a line pressure based on a required power to variably control a rotation speed of the electric oil pump, wherein the hybrid controller uses a vehicle speed, an input torque, a gear speed, an inhibiter switch position, a line pressure learned value, a real rotation speed, an input current, an input voltage, an on/off operating time of the electric oil pump, and a line pressure to calculate a viscosity of the oil.