Abstract: A power control system supplies electric power to a plurality of power consumption devices which are provided to an electric vehicle. This system includes: a high voltage battery which is an electric power supply source; a plurality of device controllers which are provided to the respective power consumption devices and which control operations of the respective power consumption devices; and an overall controller which overall controls the plurality of device controllers. At least one of the device controllers performs an electric power restriction that restricts a consumed electric power in a corresponding power consumption device so as to allow the consumed electric power in the corresponding power consumption device to fall within an electric power allocated by the overall controller while simultaneously maintaining an operation of the corresponding power consumption device stably.

Abstract: An electric compressor includes a compression portion discharging a high pressure refrigerant by compressing a low-pressure drawn refrigerant, an electric motor driving the compression portion with a rotation of a rotor, a motor drive circuit driving the electric motor, an intermediate pressure port through which an intermediate pressure refrigerant is introduced into the compression portion, and a controller performing a rotation control of the rotor. When the controller stops the electric motor in a two-step compression mode in which the intermediate pressure refrigerant is introduced into the compression portion, the controller stops the rotor rotating by performing short-circuit braking on the electric motor and then fixes a rotational position of the rotor at a predetermined rotational position by performing direct current excitation on the electric motor.

Abstract: An air conditioning apparatus includes an electric compressor, an inverter, a temperature detection element, and an ECU. The electric compressor compresses a refrigerant drawn from a refrigerant intake port and discharges the refrigerant from a refrigerant discharge port. The inverter is integrated with the electric compressor so as to be cooled by the drawn refrigerant, and operates the electric compressor according to a control signal. The temperature detection element detects a temperature of the inverter. The ECU outputs a control signal to control the inverter. The ECU performs any one or both of a control for reducing a self-cooling amount of the electric compressor and a control for increasing a self-heat generation amount of the inverter with respect to the inverter when the temperature detected by the temperature detection element is lower than a predetermined reference temperature.

Abstract: An electric compressor includes a compression portion discharging a high pressure refrigerant by compressing a low-pressure drawn refrigerant, an electric motor driving the compression portion with a rotation of a rotor, a motor drive circuit driving the electric motor, an intermediate pressure port through which an intermediate pressure refrigerant is introduced into the compression portion, and a controller performing a rotation control of the rotor. When the controller stops the electric motor in a two-step compression mode in which the intermediate pressure refrigerant is introduced into the compression portion, the controller stops the rotor rotating by performing short-circuit braking on the electric motor and then fixes a rotational position of the rotor at a predetermined rotational position by performing direct current excitation on the electric motor.

Abstract: An air conditioner for a vehicle has a compressor, a radiator, a first pressure reducer, a gas-liquid separator, a second pressure reducer, an exterior heat exchanger, an intermediate pressure refrigerant passage, a switching device, and a controller. The controller operates the switching device to switch from a refrigerant circuit of a two-stage compression mode to a refrigerant circuit of a single-stage compression mode when a compressor stop signal is output in the two-stage compression mode. The single-stage compression mode is a mode that blocks at least a flow of an intermediate-pressure refrigerant into the intermediate pressure refrigerant passage and makes refrigerant remained in the intermediate pressure refrigerant passage to flow out of the intermediate pressure refrigerant passage. The controller stops the compressor after controls the compressor to continue operating for a specified time in the single-stage compression mode.

Abstract: An onboard electric system includes a drive circuit that drives an electric motor based on an output voltage of a direct current power supply; a first smoothing capacitor; a drive signal generator; a first discharge resistor that is connected between a positive electrode and a negative electrode of the first smoothing capacitor; a first discharge switcher that is connected in series to the first discharge resistor between the positive electrode and the negative electrode, and releases or makes a connection between the positive electrode and the negative electrode; and an off-signal generator that outputs an off signal to the first discharge switcher. The first discharge switcher is provided by a switcher of a normally-ON type that makes the connection between the positive electrode and the negative electrode through the first discharge resistor in a period other than a period while the off-signal generator provides the off signal.

Abstract: A CPU drives an inverter based on a command rotation speed that is inputted from a higher level ECU at a predetermined update interval. The CPU acquires an actual rotation speed of the electric motor, and calculates an accelerated rate and a decelerated rate based on the update interval and a difference between the actual rotation speed and the command rotation speed such that the actual rotation speed changes without reaching the command rotation speed and becoming constant before an end of the update interval. The CPU drives the inverter such that the electric motor rotates at the calculated rate.

Abstract: A power control system supplies electric power to a plurality of power consumption devices which are provided to an electric vehicle. This system includes: a high voltage battery which is an electric power supply source; a plurality of device controllers which are provided to the respective power consumption devices and which control operations of the respective power consumption devices; and an overall controller which overall controls the plurality of device controllers. At least one of the device controllers performs an electric power restriction that restricts a consumed electric power in a corresponding power consumption device so as to allow the consumed electric power in the corresponding power consumption device to fall within an electric power allocated by the overall controller while simultaneously maintaining an operation of the corresponding power consumption device stably.

Abstract: An air conditioner for a vehicle has a compressor, a radiator, a first pressure reducer, a gas-liquid separator, a second pressure reducer, an exterior heat exchanger, an intermediate pressure refrigerant passage, a switching device, and a controller. The controller operates the switching device to switch from a refrigerant circuit of a two-stage compression mode to a refrigerant circuit of a single-stage compression mode when a compressor stop signal is output in the two-stage compression mode. The single-stage compression mode is a mode that blocks at least a flow of an intermediate-pressure refrigerant into the intermediate pressure refrigerant passage and makes refrigerant remained in the intermediate pressure refrigerant passage to flow out of the intermediate pressure refrigerant passage. The controller stops the compressor after controls the compressor to continue operating for a specified time in the single-stage compression mode.

Abstract: A CPU drives an inverter based on a command rotation speed that is inputted from a higher level ECU at a predetermined update interval. The CPU acquires an actual rotation speed of the electric motor, and calculates an accelerated rate and a decelerated rate based on the update interval and a difference between the actual rotation speed and the command rotation speed such that the actual rotation speed changes without reaching the command rotation speed and becoming constant before an end of the update interval. The CPU drives the inverter such that the electric motor rotates at the calculated rate.

Abstract: An air conditioning apparatus includes an electric compressor, an inverter, a temperature detection element, and an ECU. The electric compressor compresses a refrigerant drawn from a refrigerant intake port and discharges the refrigerant from a refrigerant discharge port. The inverter is integrated with the electric compressor so as to be cooled by the drawn refrigerant, and operates the electric compressor according to a control signal. The temperature detection element detects a temperature of the inverter. The ECU outputs a control signal to control the inverter. The ECU performs any one or both of a control for reducing a self-cooling amount of the electric compressor and a control for increasing a self-heat generation amount of the inverter with respect to the inverter when the temperature detected by the temperature detection element is lower than a predetermined reference temperature.

Abstract: An onboard electric system includes a drive circuit that drives an electric motor based on an output voltage of a direct current power supply; a first smoothing capacitor; a drive signal generator; a first discharge resistor that is connected between a positive electrode and a negative electrode of the first smoothing capacitor; a first discharge switcher that is connected in series to the first discharge resistor between the positive electrode and the negative electrode, and releases or makes a connection between the positive electrode and the negative electrode; and an off-signal generator that outputs an off signal to the first discharge switcher. The first discharge switcher is provided by a switcher of a normally-ON type that makes the connection between the positive electrode and the negative electrode through the first discharge resistor in a period other than a period while the off-signal generator provides the off signal.

Abstract: An electric compressor, wherein an inverter device, which controls the operation of an electric motor by commands from an external control unit, is provided with a drive IC which computes drive signals of the electric motor based on the same, a switching circuit which converts the drive signals to rotation control signals of the electric motor, and an output signal control IC which cuts off input of the drive signals to the switching circuit at the time of an abnormality and wherein, furthermore, the drive IC is provided with a comparator which compares drive signals which are input to the switching circuit and computed values of the drive signals at a control unit inside the drive IC and, when the drive signals and the computed values do not match, the comparator makes the output signal control IC cut off input of the drive signals to the switching circuit.

Abstract: An inverter circuit for a motor outputs three-phase AC currents, which are outputted from common connection points to stator coils, based on output voltage of a DC power source and a power supply capacitor by a switching operation of transistors. An inverter control circuit determines that a system main relay is turned off, upon receiving a main relay-off signal from an electronic control unit. The inverter control circuit turns on the low-side transistors, while turning off the high-side transistors. A discharge current flows from the positive electrode to the negative electrode of the power supply capacitor through the stator coil and the low-side transistors, so that electric charge stored in the power supply capacitor is discharged.

Abstract: An electric compressor, wherein an inverter device, which controls the operation of an electric motor by commands from an external control unit, is provided with a drive IC which computes drive signals of the electric motor based on the same, a switching circuit which converts the drive signals to rotation control signals of the electric motor, and an output signal control IC which cuts off input of the drive signals to the switching circuit at the time of an abnormality and wherein, furthermore, the drive IC is provided with a comparator which compares drive signals which are input to the switching circuit and computed values of the drive signals at a control unit inside the drive IC and, when the drive signals and the computed values do not match, the comparator makes the output signal control IC cut off input of the drive signals to the switching circuit.

Abstract: An inverter circuit for a motor outputs three-phase AC currents, which are outputted from common connection points to stator coils, based on output voltage of a DC power source and a power supply capacitor by a switching operation of transistors. An inverter control circuit determines that a system main relay is turned off, upon receiving a main relay-off signal from an electronic control unit. The inverter control circuit turns on the low-side transistors, while turning off the high-side transistors. A discharge current flows from the positive electrode to the negative electrode of the power supply capacitor through the stator coil and the low-side transistors, so that electric charge stored in the power supply capacitor is discharged.

Abstract: A mounting structure of a motor drive circuit and an electric compressor are disclosed. A sub-communication circuit 50a of a communication circuit 50 is accommodated in a depression 11v of a compressor housing 11. Semiconductor switching devices S1 to S6 are arranged on the flat mounting portion 11t of the compressor housing 11, i.e. on the outside of the depression 11v. As a result, the sub-communication circuit 50a can be isolated from the semiconductor switching devices S1 to S6. Although the switching operation of the semiconductor switching devices S1, S2, . . . , S6 generates electromagnetic noise, since the sub-communication circuit 50a is accommodated in the depression 11v, the sub-communication circuit 50a receives less electromagnetic noise.