Abstract: [Problem] To provide a hybrid wheel loader capable of highly efficient and stable supply of motive power. [Solution] A hybrid wheel loader including: a front work machine (5) provided at the front of a vehicle; power sources including an engine (1) and an electric storage device; and a hybrid control device (20) which controls output of these power sources; characterized in that: a capacitor (11) is provided as the electric storage device; and the hybrid control device makes control to decrease a voltage of the capacitor in accordance with increase of energy held by the vehicle.

Abstract: A construction machine or industrial vehicle having a power supply system which includes a chargeable and dischargeable capacitor and a feeder circuit connecting a battery and the capacitor to a load capable of power running and regeneration. The capacitor is connected through a DC/DC converter which includes a controller that controls energy charged or discharged by the capacitor through the DC/DC converter to the load. The controller includes a power running/regeneration operation estimater which estimates an operation pattern including a point of change between power running and regeneration modes of the motor, or DC current supplied to an inverter, or control lever information and previously stored operation pattern information, and a capacitor target voltage calculator which controls an output command value of the DC/DC converter according to the estimated operation pattern so that a capacitor target voltage sequentially decreases in power running and sequentially increases in regeneration.

Abstract: When the total value of demanded hydraulic power and demanded traveling power is larger than the sum of the engine power that can be output by an engine (1) and of the discharge power that can be discharged by an electrical storage device (3), the actual power of a hydraulic pump (9) is increased from the value at the time of demand toward the demanded hydraulic power under the constraint of a predetermined limit. While the power of the hydraulic pump is being subjected to the predetermined limit, the actual power of the traveling motor is decreased from the value at the time of demand by a value smaller than the magnitude of the predetermined limit. This prevents worsening of ride comfort attributable to the distribution of power between the hydraulic pump and the traveling motor.

Abstract: There are provided an electric storage device (11), inverter devices (7, 10), a converter device (12) for converting the voltage of circuits to which the inverter devices (7, 10) are connected, a motor generator (6) for driving a hydraulic pump (4) using alternate current from the inverter device (7), a motor (9) for driving wheels (61) using alternate current from the inverter device (10), and a control device (200) for controlling the inverter devices (7, 10). When any of the devices necessary for supplying the current to the motor (9) has developed a failure, the control device (200) drives the motor (9) by getting another normal device to perform another process corresponding to the process that has been performed by the malfunctioned device before the failure. This makes it possible to continue travel movement even when part of a travel power supply system has developed a failure.

Abstract: A hybrid wheel loader is provided, the hybrid wheel loader achieving high work efficiency even with a short supply of power to be output relative to a vehicle power requirement. The hybrid wheel loader includes a motor generator 6 connected to an engine (1), a hydraulic pump (4) connected to the motor generator, a hydraulic actuator (51, 52, 53) driven by hydraulic oil supplied from the hydraulic pump, a travel electric motor (9) for driving wheels (61), and an electrical storage device (11) connected to each of the motor generator and the electrical storage device via respective inverters (7, 10). When a total requirement power value is greater than a hybrid output upper limit value, either one of a hydraulic requirement power value Pf and a travel requirement power value Prun is limited according to an operation of the wheel loader to thereby set the total requirement power value to a value equal to, or less than, the hybrid output upper limit value.

Abstract: A construction vehicle control apparatus is provided including: a motor generator control unit (160) which, when regenerative electrical power generated by a motor (7) during regenerative braking surpasses acceptable charging electrical power of a capacitor (3), drives a motor generator (5) using the surplus electrical power; an engine controller (2) which detects the rotating speed of an engine (1); a motor control unit (180) which, if the rotating speed of the engine becomes larger than a second set value while the motor generator is being driven by the surplus electrical power, reduces regenerative torque generated by the motor; and a brake control unit (190) which, if the rotating speed of the engine becomes larger than the second set value while the motor generator is being driven by the surplus electrical power, increases regenerative torque generated by a hydraulic brake (30).

Abstract: An electric drive vehicle having an induction motor for braking or driving wheels, a motor controller for controlling the induction motor, and mechanical brakes for braking the wheels, wherein while the vehicle is in halt in a state that the mechanical breaks are not operating, the motor controller applies DC voltage or AC voltage in a frequency range of ?1 Hz to +1 Hz to the stator of the induction motor to make the induction motor generate torque for stopping the vehicle and maintain the vehicle in a halt state.

Abstract: [Problem] To provide a hybrid work vehicle which is simple in configuration, good in ease of mounting on a vehicle and capable of efficiently transmitting motive power. [Solution] The hybrid work vehicle includes: an engine (1); a hydraulic pump (4) which is driven by the engine; a work device (5) which is disposed at the front of the vehicle and performs work using the hydraulic pump as a drive source; a motor/generator (6) which generates electric power by use of the torque of the engine; and a travel drive device which causes the vehicle to travel by rotating and driving wheels by use of the electric power generated by the motor/generator. The hybrid work vehicle is steered while the vehicle bends by way of a center joint (15). The travel drive device includes: a plurality of electric motors (21 and 22); and a propeller shaft (8) which is linked with the plurality of electric motors and transmits motive power from the plurality of electric motors to the wheels.

Abstract: [Problem] To provide a hybrid wheel loader capable of highly efficient and stable supply of motive power. [Solution] A hybrid wheel loader including: a front work machine (5) provided at the front of a vehicle; power sources including an engine (1) and an electric storage device; and a hybrid control device (20) which controls output of these power sources; characterized in that: a capacitor (11) is provided as the electric storage device; and the hybrid control device makes control to decrease a voltage of the capacitor in accordance with increase of energy held by the vehicle.

Abstract: Provided is an actuator control system capable of suppressing vibrations during regeneration.

Abstract: Provided is a drive control device for a working vehicle, this device controlling motive power to be virtually invariant, even during switching of traveling drive devices, and having high-efficiency characteristics. The working vehicle has a first traveling drive device 12 including an engine 1, an electric power generator 2, a hydraulic pump 11, a torque converter 5, and a transmission 6, and a second traveling drive device 13 for driving an electric motor 8 to make the vehicle travel. Driving-force switching means 20A2 switches the first traveling drive device 12 and the second traveling drive device 13. A traveling means switcher 20A2 selects one of the two traveling drive devices, depending upon a traveling speed of the vehicle, so as to make the vehicle travel while being driven in a high-speed region with the first traveling drive device and in a low-speed region with the second traveling drive device.

Abstract: A semiconductor power conversion apparatus capable of protecting an IGBT from an overvoltage by supplying a sufficient gate current to the gate of the IGBT. The IGBT is protected from the overvoltage by connecting clamping elements connected in series between a collector of the IGBT and the gate thereof, and by connecting a resistor to each of different junction points between the clamping elements connected in series.

Abstract: An electric drive vehicle having a power generator coupled to an engine, a first power converter connected with the power generator for converting the AC power generated by the power generator to DC power, a second power converter connected with the first power converter, for converting the DC power to AC power, a power consuming device for consuming the DC power, connected to a DC circuit between the first and second power converters, an electric motor connected with the second power converter, and at least one wheel driven by the electric motor, wherein the vehicle has a first control mode for controlling the output of the electric motor and a second control mode for controlling the power consumed by the power consuming device, and the second control mode performs such control that the operations of the second power converter and the electric motor in the first control mode are simulated.

Abstract: A construction machine or industrial vehicle having a power supply system which includes a chargeable and dischargeable capacitor and a feeder circuit connecting a battery and the capacitor to a load capable of power running and regeneration. The capacitor is connected through a DC/DC converter which includes a controller that controls energy charged or discharged by the capacitor through the DC/DC converter to the load. The controller includes a power running/regeneration operation estimater which estimates an operation pattern including a point of change between power running and regeneration modes of the motor, or DC current supplied to an inverter, or control lever information and previously stored operation pattern information, and a capacitor target voltage calculator which controls an output command value of the DC/DC converter according to the estimated operation pattern so that a capacitor target voltage sequentially decreases in power running and sequentially increases in regeneration.

Abstract: [Object] To enable stable cargo handling operation and high-efficiency recovery of regenerative electric power by means of simple configuration. [Solution] In a forklift which includes linear actuators that convert rotational motion into linear motion, the linear actuators being provided in a plurality of fork parts of a cargo handling drive device, the forklift includes induction motors that drive each of the plurality of actuators provided in the plurality of fork parts, an inverter that drives the induction motors in the same manner, and a controller that controls the inverter, and the controller computes a slip frequency by using the lowest detection value among detection values from detectors that detect each of rotation speeds of the plurality of induction motors.

Abstract: A semiconductor power conversion apparatus capable of protecting an IGBT from an overvoltage by supplying a sufficient gate current to the gate of the IGBT. The IGBT is protected from the overvoltage by connecting clamping elements connected in series between a collector of the IGBT and the gate thereof, and by connecting a resistor to each of different junction points between the clamping elements connected in series.

Abstract: An energy saving type feeder voltage compensation apparatus improved in availability at low temperatures, wherein when a electric energy storage apparatus is lower in temperature than a predetermined value, an output voltage output to a feeder side is made equal to or higher than a no-load output voltage of a substation connected in parallel. Power is supplied to a power running rolling stock preferentially from the electric energy storage apparatus. The heating value of the secondary battery is increased and the battery temperature is raised by this discharging, whereby internal resistance of the electric energy storage apparatus is lowered, and the charging and discharging loss is suppressed, and the efficiency and availability of the energy saving type feeder voltage compensation apparatus as a whole are improved.

Abstract: An electric drive vehicle having a power generator coupled to an engine, a first power converter connected with the power generator for converting the AC power generated by the power generator to DC power, a second power converter connected with the first power converter, for converting the DC power to AC power, a power consuming device for consuming the DC power, connected to a DC circuit between the first and second power converters, an electric motor connected with the second power converter, and wheels driven by the electric motor, wherein the vehicle has a first control mode for controlling the output of the electric motor and a second control mode for controlling the power consumed by the power consuming device, and the second control mode performs such control that the operations of the second power converter and the electric motor in the first control mode are simulated.

Abstract: In an electrically driven vehicle having a controller, the vehicle has a steering angle sensor for outputting a detected value of a steering angle of the vehicle, the controller includes a first torque order pattern along which a torque order for a first electric motor is determined and a second torque order pattern along which a torque order for a second electric motor is determined, and the first and second torque order pattern are modified on the basis of the detected value of the steering angle so that the torque order determined along the second torque order pattern is greater than the torque order determined along the first torque order pattern under the identical velocity when the vehicle turns to the left, and the torque order determined along the first torque order pattern is greater than the torque order determined along the second torque order pattern under the identical velocity when the vehicle turns to the right.

Abstract: An energy saving type feeder voltage compensation apparatus improved in availability at low temperatures, wherein when a electric energy storage apparatus is lower in temperature than a predetermined value, an output voltage output to a feeder side is made equal to or higher than a no-load output voltage of a substation connected in parallel. Power is supplied to a power running rolling stock preferentially from the electric energy storage apparatus. The heating value of the secondary battery is increased and the battery temperature is raised by this discharging, whereby internal resistance of the electric energy storage apparatus is lowered, and the charging and discharging loss is suppressed, and the efficiency and availability of the energy saving type feeder voltage compensation apparatus as a whole are improved.