摘要:
An apparatus for estimating rotor position for brushless motors capable of accurately estimating rotor position is provided. The apparatus may be used as a start-up system for brushless motors. The apparatus performs accurate estimation even though power source voltage fluctuates, and is able to provide compact configuration. The apparatus supplies voltage to the coils respectively. In each supplying period, the apparatus counts voltage supply period of time until current value reaches to a current threshold value. Since a coil indicative of rotor stop position is prone to be magnetically saturated. The apparatus estimates the rotor stop position based on the voltage supply periods. Then, the apparatus starts a switching sequence based on the rotor stop position.
摘要:
An apparatus for estimating rotor position for brushless motors capable of accurately estimating rotor position is provided. The apparatus may be used as a start-up system for brushless motors. The apparatus performs accurate estimation even though power source voltage fluctuates, and is able to provide compact configuration. The apparatus supplies voltage to the coils respectively. In each supplying period, the apparatus counts voltage supply period of time until current value reaches to a current threshold value. Since a coil indicative of rotor stop position is prone to be magnetically saturated. The apparatus estimates the rotor stop position based on the voltage supply periods. Then, the apparatus starts a switching sequence based on the rotor stop position.
摘要:
An apparatus for estimating rotor position for brushless motors capable of accurately estimating rotor position even though power source voltage fluctuates is provided. First, the power source voltage is detected, and voltage is supplied only for a certain period of time and a current response is detected. The current detection value is multiplied by the ratio of a reference voltage to the power source voltage detected to correct the current detection value. Specifically, the peak current detection value is corrected upwardly or downwardly in each direction. A voltage supplying direction in which the current detection value is maximized is searched for to estimate the rotor position and a brushless motor is started.
摘要:
An electric fuel pump is disclosed which includes a pump portion, a motor portion, a housing, and a fuel passage. The pump portion pressurizes fuel. The motor portion drives the pump portion. The motor portion includes a rotor with a rotating shaft and a stator that surrounds an outer periphery of the rotor. The housing surrounds, at least, an outer periphery of the stator of the motor portion. The fuel passage, through which the fuel pressurized by the pump portion passes the motor portion, is made up of a clearance between the outer periphery of the stator of the motor portion and an inner periphery of the housing. The clearance extends, at least, in the axial direction of the rotating shaft of the rotor of the motor portion.
摘要:
A motor driving apparatus has a loss-of-synchronism monitoring circuit that monitors the rotation of a rotary machine such as a brushless DC motor to detect a sign of transition to a state of loss of synchronism. When the sign is detected, an energization control circuit temporarily stops driving of the rotary machine to bring it into a free running state, and thereafter carries out control so as to resume driving of the rotary machine. Further, the motor driving apparatus has an inverter and a drive control circuit that controls switching operation of the inverter based on rotation of the rotary machine.
摘要:
An electric fuel pump is disclosed which includes a pump portion, a motor portion, a housing, and a fuel passage. The pump portion pressurizes fuel. The motor portion drives the pump portion. The motor portion includes a rotor with a rotating shaft and a stator that surrounds an outer periphery of the rotor. The housing surrounds, at least, an outer periphery of the stator of the motor portion. The fuel passage, through which the fuel pressurized by the pump portion passes the motor portion, is made up of a clearance between the outer periphery of the stator of the motor portion and an inner periphery of the housing. The clearance extends, at least, in the axial direction of the rotating shaft of the rotor of the motor portion.
摘要:
A control system controls a multiphase rotating machine by a 120° energization process and a PWM process. In the 120° energization process, respective ones of switching elements of a high side arm and switching elements of a low side arm of a power conversion circuit are turned on. In the PWM process, the switching elements of the power conversion circuit turn on/off so that two phases that are connected to the switching elements that are in the on-state are alternately rendered conductive to the high potential side input terminal and the low potential side input terminal of the power conversion circuit.
摘要:
A motor driving apparatus has a loss-of-synchronism monitoring circuit that monitors the rotation of a rotary machine such as a brushless DC motor to detect a sign of transition to a state of loss of synchronism. When the sign is detected, an energization control circuit temporarily stops driving of the rotary machine to bring it into a free running state, and thereafter carries out control so as to resume driving of the rotary machine. Further, the motor driving apparatus has an inverter and a drive control circuit that controls switching operation of the inverter based on rotation of the rotary machine.
摘要:
A motor driving apparatus has a loss-of-synchronism monitoring circuit that monitors the rotation of a rotary machine such as a brushless DC motor to detect a sign of transition to a state of loss of synchronism. When the sign is detected, an energization control circuit temporarily stops driving of the rotary machine to bring it into a free running state, and thereafter carries out control so as to resume driving of the rotary machine. Further, the motor driving apparatus has an inverter and a drive control circuit that controls switching operation of the inverter based on rotation of the rotary machine.
摘要:
A motor driving apparatus has a loss-of-synchronism monitoring circuit that monitors the rotation of a rotary machine such as a brushless DC motor to detect a sign of transition to a state of loss of synchronism. When the sign is detected, an energization control circuit temporarily stops driving of the rotary machine to bring it into a free running state, and thereafter carries out control so as to resume driving of the rotary machine. Further, the motor driving apparatus has an inverter and a drive control circuit that controls switching operation of the inverter based on rotation of the rotary machine.