An electric motor control device includes an electronic control unit configured to perform switching control of a switching element of an inverter in PWM control mode when a modulation degree is less than a first predetermined value, perform switching control of the switching element in square wave control mode when the modulation degree is greater than or equal to a second predetermined value, and perform switching control of the switching element in intermediate control mode when the modulation degree is greater than or equal to the first predetermined value and less than the second predetermined value. The intermediate control mode uses a switching pattern in which, in a pulse pattern in the square wave control mode, a slit or a short pulse having the same width as the slit is formed according to whether a pulse is present at the time when a phase current crosses zero.

In a method and system for operating a system having an energy storage device and a resistor, and in order to discharge the energy storage device, an electric power that is constant over time is continuously supplied to the resistor, e.g., during a time period, e.g., until the resistor has practically been fully discharged, the time period, e.g., being greater than the time constant of the temperature rise of the resistor induced by a continuous electric power that is constant over time and supplied to the resistor.

An electric device is provided which can reduce risk of malfunction. This electric device is provided with a motor (31), an inverter circuit (30) which has switching elements (S1-S6) and which drives the motor (31), and a charge pump circuit (22) which generates the drive voltage of the switching elements (S1-S6). A discharge circuit (a discharge resistor R and a capacitor C1) is provided between a power line to which a drive voltage (VM) of the motor (31) is supplied and an output terminal (a VGT terminal) of the charge pump circuit (22). Energy of the surge voltage (Vs) generated in a parasitic inductance (Ls) when the switching elements (S4-S6) are turned off is absorbed by the discharge circuit (the discharge resistor R and the capacitor C1).

A converter device includes: a power conversion circuit including a reactor and a switching element, rectifying a voltage of alternating-current power supplied from an alternating-current power supply to a direct-current voltage, and boosting and outputting the direct-current voltage; a current detector detecting a current flowing in the reactor; a filter circuit filtering a first signal detected by the current detector; and a control unit generating a control signal on the basis of a carrier and a second signal generated by the filter circuit and controlling, on the basis of the control signal and with a first period, the switching element, the first period being a period of the carrier. The filter circuit cuts off a repetition frequency component in the first period and passes a repetition frequency component in a second period, the second period being longer than the first period.

A circuit that increases input voltage to higher output voltage connected to a drive. The circuit can include a power input that receives the input voltage from a power source and at least one capacitor bank connected with the power input. A current-limiting surge suppressor is positioned between the power input and the at least one capacitor bank. The current-limiting surge suppressor includes a first current-limiting path and a second bypass path. A drain, when operable, dissipates the charge of the at least one capacitor bank. The drive is operable in response to the higher voltage output from the at least one capacitor bank.

An example electrical system is disclosed. The electrical system can include a rechargeable energy storage system (RESS) and a power inverter connected to the RESS. The power inverter can be configured to provide electrical power to a traction motor. The electrical system can include a plurality of machine windings connected between the power inverter and a switch. The switch can be configured to transition between a closed state to allow current flow from an off-board power source through the plurality of machine windings to the RESS and an open state to prevent current flow between the off-board power source and the plurality of machine windings.

Provided is an electric linear motion actuator that enables size reduction and cost reduction while increasing the instantaneous output of an electric motor. A control device (2) of the electric linear motion actuator includes: a motor driver (24) configured to control power supplied to a coil (4b) of an electric motor (4); a power storage unit (21) connected to a power supply device (3) and the motor driver (24); a current flow direction restriction unit (20) disposed between the power supply device (3) and the power storage unit (21), which causes current to pass only in a direction in which power is supplied from the power supply device (3); and a step-up unit (19) configured to step up voltage of the power supply device (3) and provide the stepped-up voltage to the power storage unit (21).

In a method and system for operating a system having an energy storage device and a resistor, and in order to discharge the energy storage device, an electric power that is constant over time is continuously supplied to the resistor, e.g., during a time period, e.g., until the resistor has practically been fully discharged, the time period, e.g., being greater than the time constant of the temperature rise of the resistor induced by a continuous electric power that is constant over time and supplied to the resistor.

A power device includes: a DC voltage output circuit that generates a DC internal power voltage from external supply power; a capacitor that is connected to the internal power voltage; and a voltage supply control circuit that monitors a voltage level of the internal power voltage and that, when detecting a drop in the internal power voltage, cuts off supply of the internal power voltage. The power device supplies internal power to a load. The power device supplies, to a first load that is a part of the load, the internal power voltage, and supplies, to a second load that is a load other than the first load, the internal power voltage via the voltage supply control circuit.

An example of a vehicle electrical system includes a rechargeable energy storage system (RESS) having a first voltage and a power inverter selectively connected to the RESS. The system further includes an electric motor having a plurality of machine windings with each of the machine windings including a polyphase terminal electrically connected to the power inverter. The machine windings further include a neutral terminal separate from the polyphase terminals and configured to electrically connect to an off-board power source having a second voltage that is below the first voltage of the RESS. The power inverter is configured to cycle between first and second operational states, such that the power inverter and the electric motor steps up the first voltage to the second voltage.