A power converting apparatus includes: a rectifying unit configured to rectify an input AC power, a buck converter that is configured to step down a voltage of the rectified power and that is configured to output DC power having the step down voltage, a first inverter that is connected to an output terminal of the buck converter and that is configured to convert the DC power into AC power to drive a first motor, a second inverter that is connected to the output terminal of the buck converter, that is disposed in parallel to the first inverter, and that is configured to convert the DC power into AC power to drive a second motor, and a converter controller configured to control an output voltage of the DC power of the buck converter.

To provide a system of low cost and low loss capable of the supply of electric power according to characteristics of each of a plurality of motors from a single battery. A power supply system for a vehicle of the present invention includes: a high-voltage battery; a first inverter which connects with the high-voltage battery; a motor described later which connects with the first inverter; a high-voltage DCDC converter which is connected to the high-voltage battery and steps down the voltage of the high-voltage battery; a second inverter which connects with the high-voltage battery; and a motor described later which connects with the second inverter.

Apparatus and methods are provided for operating an electric motor, comprising selectively energising the coils of a stator having a plurality of stator teeth, each stator tooth having a said coil mounted thereon. The stator coils of a subset of the stator teeth are energised during a given time period to attract a corresponding rotor tooth into alignment with each of the stator teeth in the subset over the given time period. The stator coil of at least one stator tooth in the subset is energised during a portion of the given time period before the at least one stator tooth overlaps the corresponding rotor tooth.

A motor control system for operating an electric motor is described. The motor control system includes a power supply module disposed external to the electric motor and configured to convert an alternating current (AC) voltage at a first level to a direct current (DC) voltage at a second level lower than a DC-equivalent voltage of the AC voltage at the first level, and a motor control assembly coupled to the electric motor. The motor control assembly includes an input power connector configured to receive the DC voltage at the second level from the power supply module. The motor control assembly also includes an inverter module coupled to the input power connector. The inverter module is configured to convert the DC voltage at the second level to an AC motor voltage to operate the electric motor.

A loss in each of a converter, an inverter, and a motor changes according to operation based on the rotation speed of the motor or the like. Thus, in order to efficiently perform operation, appropriate control needs to be performed according to the voltage of a DC power supply and operation of the motor. The present disclosure is characterized by including a controller which controls a switching element of a converter according to the torque and the rotation speed of a motor on the basis of a loss in at least one of the motor, an inverter, and the converter.

A motor control system for operating an electric motor is described. The motor control system includes a power supply module disposed external to the electric motor and configured to convert an alternating current (AC) voltage at a first level to a direct current (DC) voltage at a second level lower than a DC-equivalent voltage of the AC voltage at the first level, and a motor control assembly coupled to the electric motor. The motor control assembly includes an input power connector configured to receive the DC voltage at the second level from the power supply module. The motor control assembly also includes an inverter module coupled to the input power connector. The inverter module is configured to convert the DC voltage at the second level to an AC motor voltage to operate the electric motor.

An electric power conversion system includes: an inverter; a voltage converter including a high-voltage end connected to a direct-current power source and a low-voltage end connected to the inverter; and a controller. The controller is configured to control switching elements such that a voltage of the low-voltage end becomes lower than a voltage of the high-voltage end in a first state. The controller is configured to control the switching elements such that the voltage of the low-voltage end becomes equal to the voltage of the high-voltage end in a second state.

A motor control device includes a temperature input unit that inputs a temperature of a motor and a control unit that performs control such that the control unit drives the motor by constant current/variable voltage control by lowering a power source voltage in a case in which the input temperature of the motor is equal to or less than a first threshold value and drives the motor by constant voltage/variable current control at a predetermined power source voltage in a case in which the temperature of the motor exceeds the first threshold value.

A control unit calculates necessary power necessary to drive a motor in accordance with a torque designation value and a rotational speed of a motor, sets a voltage value to a predetermined voltage value, changes a current value in accordance with the necessary power, and drive the motor in a case in which the calculated necessary power is less than a predetermined threshold value, and sets the current value to a predetermined current value, changes the voltage value in accordance with the necessary power, and drives the motor in a case in which the calculated necessary power is equal to or greater than the predetermined threshold value.

Apparatus and methods are provided for operating an electric motor, comprising selectively energizing the coils of a stator having a plurality of stator teeth, each stator tooth having a said coil mounted thereon. The stator coils of a subset of the stator teeth are energized during a given time period to attract a corresponding rotor tooth into alignment with each of the stator teeth in the subset over the given time period. The stator coil of at least one stator tooth in the subset is energized during a portion of the given time period before the at least one stator tooth overlaps the corresponding rotor tooth.