An electric drive system for mechanical machinery. The electric drive system includes a first electrical bus and a second electrical bus each configured to operate at different voltages. A first generator is configured to provide electric current to the first electrical bus at a first voltage. A second generator is configured to provide electric current to the second electrical bus at a second voltage that is different from the first voltage. A first electric motor is coupled to the first electrical bus and configured to operate on electrical power from the first electrical bus at the first voltage. A second electric motor is coupled to the second electrical bus and configured to operate on electrical power from the second electrical bus at the second voltage. Mechanical power used to drive the mechanical machinery is generated by both the first electric motor and the second electric motor.

An electric power conversion system includes: an AC-DC conversion circuit converting AC charging power into DC power; a motor including a plurality of coils, one end of each being connected to a neutral point; a first switching device selectively allowing or blocking supply of output power from the AC-DC conversion circuit to the neutral point; an inverter including a plurality of motor connection terminals connected to the other ends of the coils of the motor, respectively, DC connection terminals including a positive terminal and a negative terminal, and a plurality of switching elements forming electrical connections between the DC connection terminals and the plurality of motor connection terminals; a battery connected to the DC connection terminals of the inverter; and a controller controlling operations of the AC-DC conversion circuit, the first switching device, and the inverter in accordance with whether or not the battery is charged.

An electric power conversion system includes: an AC-DC conversion circuit converting AC charging power into DC power; a motor including a plurality of coils, one end of each being connected to a neutral point; a first switching device selectively allowing or blocking supply of output power from the AC-DC conversion circuit to the neutral point; an inverter including a plurality of motor connection terminals connected to the other ends of the coils of the motor, respectively, DC connection terminals including a positive terminal and a negative terminal, and a plurality of switching elements forming electrical connections between the DC connection terminals and the plurality of motor connection terminals; a battery connected to the DC connection terminals of the inverter; and a controller controlling operations of the AC-DC conversion circuit, the first switching device, and the inverter in accordance with whether or not the battery is charged.

An electric vehicle allows a user to experience changes in acceleration g-force, as with a conventional power plant, including: a transmission that sets a gearshift position based on a gearshift position command value to be supplied, and reduces a rotation speed of a motor with the gear ratio based on the gearshift position to rotationally drive wheels; a user operation unit that outputs the gearshift position command value and a speed control amount, based on user operation; and a controller that sets a DC voltage command value or an AC voltage command value to an operation-based value corresponding to the gearshift position and the speed control amount, and, on the condition that operation on the user operation unit satisfies a predetermined condition, sets the DC voltage command value or the AC voltage command value to a value higher than the operation-based value for causing a change in acceleration.

An electric vehicle allows a user to experience changes in acceleration g-force, as with a conventional power plant, including: a transmission that sets a gearshift position based on a gearshift position command value to be supplied, and reduces a rotation speed of a motor with the gear ratio based on the gearshift position to rotationally drive wheels; a user operation unit that outputs the gearshift position command value and a speed control amount, based on user operation; and a controller that sets a DC voltage command value or an AC voltage command value to an operation-based value corresponding to the gearshift position and the speed control amount, and, on the condition that operation on the user operation unit satisfies a predetermined condition, sets the DC voltage command value or the AC voltage command value to a value higher than the operation-based value for causing a change in acceleration.

An electric vehicle control device includes a plurality of drive control systems that controls travelling of an electric vehicle. Each of the drive control systems includes an induction motor, an inverter that drives the induction motor, and a controller that controls the inverter. Each of the controllers of the plurality of drive control systems includes a miswiring detector that calculates a torque estimation value on a basis of motor currents and voltage command values and detects miswiring between the induction motor and the inverter on a basis of the calculated torque estimation value and the torque command value.

An electric vehicle control device includes a plurality of drive control systems that controls travelling of an electric vehicle. Each of the drive control systems includes an induction motor, an inverter that drives the induction motor, and a controller that controls the inverter. Each of the controllers of the plurality of drive control systems includes a miswiring detector that calculates a torque estimation value on a basis of motor currents and voltage command values and detects miswiring between the induction motor and the inverter on a basis of the calculated torque estimation value and the torque command value.

A vehicle operates an internal combustion engine according to an automatic start-stop function to reduce fuel consumption. A first DC bus is adapted to connect to a plurality of DC loads. A primary battery is coupled between the first DC bus and a ground. A first alternator is driven by the internal combustion engine to supply electrical power to the first DC bus. A second DC bus is connected to a positive terminal of an auxiliary battery. A negative terminal of the auxiliary battery is connected to the first DC bus. A second alternator is driven by the internal combustion engine to supply electrical power to the second bus at a voltage corresponding to a sum of voltages of the primary and auxiliary batteries. An inverter receives electrical power from the second DC bus to generate an AC output adapted to connect to accessory AC loads.

A vehicle operates an internal combustion engine according to an automatic start-stop function to reduce fuel consumption. A first DC bus is adapted to connect to a plurality of DC loads. A primary battery is coupled between the first DC bus and a ground. A first alternator is driven by the internal combustion engine to supply electrical power to the first DC bus. A second DC bus is connected to a positive terminal of an auxiliary battery. A negative terminal of the auxiliary battery is connected to the first DC bus. A second alternator is driven by the internal combustion engine to supply electrical power to the second bus at a voltage corresponding to a sum of voltages of the primary and auxiliary batteries. An inverter receives electrical power from the second DC bus to generate an AC output adapted to connect to accessory AC loads.

A power conversion device control system includes a power conversion device configured to supply electric power to a rotary electric machine, and a control device configured to control the power conversion device, wherein the control device controls the power conversion device through synchronous control in which a carrier frequency of the power conversion device is proportional to a rotational speed of the rotary electric machine when a temperature of a permanent magnet provided in the rotary electric machine is higher than a predetermined threshold value, and controls the power conversion device through non-synchronous control in which a carrier frequency of the power conversion device is not proportional to a rotational speed of the rotary electric machine when a temperature of the permanent magnet is the predetermined threshold value or less.