Electric Oil Pump Device

Abstract

An electric oil pump device includes an electric oil pump and a microcomputer that acquires a static friction torque of a pump and a motor of the electric oil pump, and performs control of activating the electric oil pump based on the acquired static friction torque.

1 . An electric oil pump device comprising:
 an electric oil pump including a motor without a position detection sensor and driven by the motor; and   a controller that acquires a static friction torque of a pump and the motor of the electric oil pump based on a relationship between at least one of a torque, a motor current value, or a hydraulic pressure of the electric oil pump detected at a time of activating the electric oil pump and at least one of a rotation speed or an oil discharge amount of the electric oil pump, and performs control of activating the electric oil pump based on the acquired static friction torque.   
     
     
         2 . The electric oil pump device according to  claim 1 , wherein the controller acquires the static friction torque of the pump and the motor of the electric oil pump based on the relationship between at least one of the torque, the motor current value, or the hydraulic pressure of the electric oil pump detected at the time of activating the electric oil pump and at least one of the rotation speed or the oil discharge amount of the electric oil pump, and corrects a starting voltage and a forced commutation frequency of the motor at the time of activating the electric oil pump based on the acquired static friction torque. 
     
     
         3 . The electric oil pump device according to  claim 1 , wherein the controller acquires the static friction torque of the pump and the motor of the electric oil pump based on a torque of the electric oil pump when the electric oil pump starts to rotate. 
     
     
         4 . The electric oil pump device according to  claim 1 , further comprising a table in which the static friction torque of the pump and the motor in the electric oil pump and a starting voltage and a forced commutation frequency of the motor are associated with each other, wherein
 the controller activates the electric oil pump based on the table.   
     
     
         5 . The electric oil pump device according to  claim 1 , wherein the controller activates the electric oil pump based on a correlation expression in which a correlation between the static friction torque of the pump and the motor in the electric oil pump and a starting voltage and a forced commutation frequency of the motor is defined. 
     
     
         6 . The electric oil pump device according to  claim 2 , wherein the controller repeatedly corrects the starting voltage and the forced commutation frequency of the motor at a time of factory shipment of the electric oil pump or at the time of activating the electric oil pump. 
     
     
         7 . The electric oil pump device according to  claim 1 , wherein the controller acquires the static friction torque based on a relationship between the motor current value of the electric oil pump detected at the time of activating the electric oil pump and the rotation speed of the electric oil pump, and performs control of activating the electric oil pump based on the acquired static friction torque. 
     
     
         8 . The electric oil pump device according to  claim 2 , wherein the controller corrects the starting voltage of the motor at the time of activating the electric oil pump by changing a set value of a duty ratio.