SENSORLESS BRUSHLESS MOTOR CONTROL DEVICE AND ELECTRIC FLUID PUMP USING THE SAME

PROBLEM TO BE SOLVED: To provide a sensorless brushless motor control device that is configured at low cost and can stably control a sensorless brushless motor by smoothly switching from motor startup to current control and an electric fluid pump using the motor. SOLUTION: The sensorless brushless motor control device includes an inverter, an inverter drive circuit that drives the inverter, and a current control means that controls the inverter drive circuit according to a current command from a superior control means and includes a first-order lag compensating means. The device further includes a control mode changeover decision means that determines changeover of a control gain of the current control means after startup of the sensorless brushless motor in response to a motor revolution sensing signal from the inverter drive circuit and a control mode changeover means that changes over the control gain of the current control means in response to an output of the control mode changeover decision means. COPYRIGHT: (C)2011,JPO&INPIT