The invention includes a first power supply connector, which connects a first inverter unit that supplies a drive current to a first three-phase winding of a rotary electric machine to a first vehicle power supply, and a second power supply connector, which connects a first second inverter unit that supplies a drive current to a second three-phase winding of the rotary electric machine to a second vehicle power supply, wherein a voltage of the first vehicle power supply is higher than a voltage of the second vehicle power supply, and a current capacity of the first power supply connector is smaller than a current capacity of the second power supply connector.

The invention includes a first power supply connector, which connects a first inverter unit that supplies a drive current to a first three-phase winding of a rotary electric machine to a first vehicle power supply, and a second power supply connector, which connects a first second inverter unit that supplies a drive current to a second three-phase winding of the rotary electric machine to a second vehicle power supply, wherein a voltage of the first vehicle power supply is higher than a voltage of the second vehicle power supply, and a current capacity of the first power supply connector is smaller than a current capacity of the second power supply connector.

To provide a motor controller and an electric power steering apparatus which can suppress torque fluctuation resulting from low detection resolution of angle, with simple calculation, even in condition where the rotational speed of motor is low. A motor controller estimates an angle error correlation value correlated with the angle detection error based on the current command value when a change frequency of the angle detection value is lower than a cutoff frequency of feedback control system which controls a rotation state; corrects the current command value or the angle detection value based on the estimation value of angle error correlation value; and changes the estimation value of angle error correlation value so that the absolute value of angle detection error increases with respect to increase in the current command value, and the absolute value of angle detection error decreases with respect to decrease in the current command value.

A control unit determines a presence or absence of a short-circuit failure with respect to a target switch which is a phase-opening switch to be determined. At this time, after opening all the phase opening switches, the control unit drives an inverter to connect a power supply line provided with the target switch among the phase opening switches to ground. The control unit determines that the target switch has a short-circuit failure when a voltage of the power supply line in which the target switch is not provided is smaller than a predetermined voltage.

A control unit determines a presence or absence of a short-circuit failure with respect to a target switch which is a phase-opening switch to be determined. At this time, after opening all the phase opening switches, the control unit drives an inverter to connect a power supply line provided with the target switch among the phase opening switches to ground. The control unit determines that the target switch has a short-circuit failure when a voltage of the power supply line in which the target switch is not provided is smaller than a predetermined voltage.

Examples described herein provide a method for overspeed protection of a motor of a gate crossing mechanism. The method includes monitoring, by an overspeed protection circuit, a voltage across a first Zener diode and a second Zener diode. An anode of the first Zener diode is connected to an anode of the second Zener diode. The method further includes, responsive to determining that a Zener voltage threshold is exceeded, allowing a current to flow into a gate pin of a triac. The triac controls the motor of the gate crossing mechanism.

An electric motor system implements a redundant wye-wounded motor that includes first phase leads, second phase leads, first neutral leads, and second neutral leads. The first and second phase leads receive alternating current (AC) power from a power supply. A first phase-lead switch selectively connects the first phase leads to the power supply, and a second phase-lead switch selectively connects the second phase leads to the power supply. A first neutral-lead switch selectively connects the first neutral leads to the redundant wye-wounded motor, and a second neutral-lead switch selectively connects the second neutral leads to the redundant wye-wounded motor. A controller detects a circuit fault among a plurality of different types of circuit faults, and controls the operation of one or both of the primary neutral-lead switch and the second neutral-lead switch based on the circuit fault.

An electric motor system implements a redundant wye-wounded motor that includes first phase leads, second phase leads, first neutral leads, and second neutral leads. The first and second phase leads receive alternating current (AC) power from a power supply. A first phase-lead switch selectively connects the first phase leads to the power supply, and a second phase-lead switch selectively connects the second phase leads to the power supply. A first neutral-lead switch selectively connects the first neutral leads to the redundant wye-wounded motor, and a second neutral-lead switch selectively connects the second neutral leads to the redundant wye-wounded motor. A controller detects a circuit fault among a plurality of different types of circuit faults, and controls the operation of one or both of the primary neutral-lead switch and the second neutral-lead switch based on the circuit fault.

An apparatus includes a servo motor being configured to drive a traveling part for transferring an object along a traveling rail, a servo driver being configured to control an operation of the servo motor with adjusting a torque of the servo motor according to a load level, an overload determination unit being configured to check a degree of overload of the servo driver and a motion controller being configured to generate a speed signal and a speed profile according to a transfer command which a control unit of controlling an operation of the traveling part transmits thereto, the motion controller generating either a normal speed profile when the servo driver is not at an overload state or a corrected speed profile when the servo driver is at the overload state, and transmitting the speed signal and the speed profile to the servo driver.

An apparatus includes a servo motor being configured to drive a traveling part for transferring an object along a traveling rail, a servo driver being configured to control an operation of the servo motor with adjusting a torque of the servo motor according to a load level, an overload determination unit being configured to check a degree of overload of the servo driver and a motion controller being configured to generate a speed signal and a speed profile according to a transfer command which a control unit of controlling an operation of the traveling part transmits thereto, the motion controller generating either a normal speed profile when the servo driver is not at an overload state or a corrected speed profile when the servo driver is at the overload state, and transmitting the speed signal and the speed profile to the servo driver.