Abstract: A hybrid construction machine according to the present invention includes a controller for controlling an engine with a droop characteristic. The controller includes: a target engine output calculation unit (2-4) that calculates a target output of the engine; a target speed setting unit (2-7) that sets a target speed command of a motor-generator; a target droop calculation unit (2-8) that obtains an intersection point of a constant output line with the target output value of the engine and a constant speed line with the target speed command of the motor-generator on a speed-torque characteristic diagram, and determines a governor characteristic of the engine so that the governor characteristic passes through the intersection point; a governor characteristic changing unit (2-10) that changes the governor characteristic of the engine; and a motor-generator control unit (2-9) that controls the motor-generator in accordance with the target speed command value.

Abstract: The hybrid constructions machine has an engine rotation speed sensor 11A to detect a rotation speed NE of an engine 11, an engine state determination unit 20B to determine the state of output torque TE of the engine 11, a load torque estimation unit 20C to calculate load torque TP of a hydraulic pump 13, and an engine assistance limiting unit 20E to, when the rotation speed NE detected with the engine rotation speed sensor 11A is equal to or greater than a rotation speed N0, and the engine state determination unit 20B determines that the output torque TE of the engine 11 has not become minimum torque Tmin, or the load torque TP calculated with the load torque estimation unit 20C is lower than torque T1, limit motive-power assistance with the motor generator 12 to the engine 11.

Abstract: To provide a construction machine that appropriately sets the magnitude of an engine output for each work mode. A construction machine according to the present invention includes: an engine (22); a generator-motor (23) configured to generate electric power by the engine; a hydraulic pump (41) configured to be driven by the engine and the generator-motor; a hydraulic actuator (32, 34, 36) that drives and operates a working device (30) with the power of the hydraulic pump; an electric storage device (24) for supplying electric power to drive the generator-motor and charging the electric power generated by the generator-motor; a work-mode selecting device (45, 46) that selects a work mode corresponding to operation of an operator; and an engine-output setting unit (403, 405, 407) that sets the magnitude of the output of the engine corresponding to the work mode selected by the work-mode selecting device.

Abstract: Provided is a construction machine which is capable of suppressing useless power consumption. This construction machine is provided with an excavator body (2), a working device (30) which is attached to the excavator body (2), an engine (22) which is mounted in the excavator body (2), a generator motor (23) which is attached to the engine (22) and which can be driven as an electric generator or an electric motor, a hydraulic pump (41) which is driven by the engine (22) and the generator motor (23), a hydraulic actuator (32) which drives the working device (30) with motive power generated by the hydraulic pump (41), and a control portion (80) which lowers the drive output of the generator motor (23) in accordance with the drive state of the working device (30) and limits the drive output of the hydraulic pump (41) in order to keep the rotation frequency of the engine (22) within a range of predetermined values.

Abstract: Provided is a hybrid construction machine together with a method for controlling that construction machine in a manner ensuring the operability of its combined operations regardless of fluctuations in the load on its work machine.

Abstract: A hybrid construction machine according to the present invention includes a controller for controlling an engine with a droop characteristic. The controller includes: a target engine output calculation unit (2-4) that calculates a target output of the engine; a target speed setting unit (2-7) that sets a target speed command of a motor-generator; a target droop calculation unit (2-8) that obtains an intersection point of a constant output line with the target output value of the engine and a constant speed line with the target speed command of the motor-generator on a speed-torque characteristic diagram, and determines a governor characteristic of the engine so that the governor characteristic passes through the intersection point; a governor characteristic changing unit (2-10) that changes the governor characteristic of the engine; and a motor-generator control unit (2-9) that controls the motor-generator in accordance with the target speed command value.

Abstract: This invention is a hydraulic work machine having an electric assist motor coupled to an engine and a hydraulic pump, in the hydraulic work machine of which, a rotational speed and torque of the engine are controlled so that an operating point of the engine moves along a predetermined route for yielding a combustion state of the engine under a transient state that the engine changes in speed and torque. A target speed and torque of the engine 7 are set so that the rotational speed and torque of the engine 7 will change along a predetermined route F in a running region of the engine, respective rates of change of the target rotational speed and torque of the engine 7 are limited, and the engine 7 is controlled to yield the target engine speed. In addition, torque of the assist motor 10 is controlled to yield the target torque of the engine.

Abstract: A hybrid-driven hydraulic work machine maintains the torque of the engine at a prescribed value when the load on a hydraulic pump is higher than the rated power of the engine and the electric assist motor assists the torque of the engine. Control of the engine revolution speed is based on the target revolution speed of the engine; engine load calculation; and at least one of: electric motor power running calculation which calculates a differential revolution speed between the target engine revolution speed and the revolution speed of the engine and performs power running control on the electric assist motor depending on the differential revolution speed when the engine load is a prescribed value or higher; and a hydraulic pump absorption torque calculation which performs reduction control on absorption torque of the hydraulic pump depending on the differential revolution speed when the engine load is a prescribed value or higher.

Abstract: In a hybrid construction machine, there is provided a drive control device which realizes in, as a simple a structure as possible, control means of a motor generator, which is capable of preventing rapid decreases in the state of charge. The control means, which calculates a motor torque command value to be output to the motor generator, is characterized by calculating the motor torque command value, based on a difference between an actual state-of-charge and a prescribed target state-of-charge and a torque margin obtained by a difference between a maximum torque of an engine determined based on an actual rotational speed of the engine and an actual torque of the engine.

Abstract: A hybrid construction machine comprises: a motor generator (2) which exchanges torque with an engine (1); a hydraulic pump (3) which is driven by at least one of the engine and the motor generator; a hydraulic actuator (5) which is driven by hydraulic fluid delivered from the hydraulic pump; an electrical storage device (10) for supplying electric power to the motor generator; and a controller (8) which sets target power of the engine and target power of the motor generator so as to satisfy demanded power of the hydraulic pump. The controller makes the setting so that the target power of the engine monotonically increases with the decrease in the remaining electric amount of the electrical storage device. With this configuration, the operator's operational feel can be kept excellent while also achieving reduction in fuel consumption and gas emission.

Abstract: A vehicle control system which can ensure high reliability, real-time processing, and expandability with a simplified ECU configuration and a low cost by backing up an error through coordination in the entire system without increasing a degree of redundancy of individual controllers beyond the least necessary level. The vehicle control system comprises a sensor controller for taking in sensor signals indicating a status variable of a vehicle and an operation amount applied from a driver, a command controller for generating a control target value based on the sensor signals taken in by the sensor controller, and an actuator controller for receiving the control target value from the command controller and operating an actuator to control the vehicle, those three controller being interconnected via a network.

Abstract: There is provided an electrically driven working vehicle that needs reduced assisting power from an electrical storage device when accelerating subsequent to modulation and still obtains acceleration at least equivalent to that of torque converter vehicles. The electrically driven working vehicle has an engine 1, a generator motor 5 connected mechanically to the engine 1, a generator inverter 6 for controlling the amount of power generated by the generator motor 5, a traveling motor 7 for driving a vehicle body, an electrical storage device 3 connected electrically to the generator inverter 6 and to the traveling motor 7, and a forward/reverse switching device 103 for switching the traveling direction of the vehicle body.

Abstract: A hybrid-driven hydraulic work machine maintains the torque of the engine at a prescribed value when the load on a hydraulic pump is higher than the rated power of the engine and the electric assist motor assists the torque of the engine. Control of the engine revolution speed is based on the target revolution speed of the engine; engine load calculation; and at least one of: electric motor power running calculation which calculates a differential revolution speed between the target engine revolution speed and the revolution speed of the engine and performs power running control on the electric assist motor depending on the differential revolution speed when the engine load is a prescribed value or higher; and a hydraulic pump absorption torque calculation which performs reduction control on absorption torque of the hydraulic pump depending on the differential revolution speed when the engine load is a prescribed value or higher.

Abstract: In a control device for construction machinery, a system operating point calculation unit calculates a plurality of combinations of engine rotational speed and engine torque with which demanded power of an engine can be generated; and calculates system efficiency in each of the combinations according to discharge pressure of a hydraulic. A rotational speed calculation unit calculates target rotational speed of the engine as the engine rotational speed in one of the combinations of the engine rotational speed, the engine torque and the system efficiency calculated by the system operating point calculation unit that includes desired system efficiency. A displacement calculation unit calculates target displacement of the hydraulic pump based on the target rotational speed calculated by the rotational speed calculation unit and demanded flow rate of the hydraulic pump. With this control device, the engine and the hydraulic pump can be controlled at an efficient operating point.

Abstract: Target rotation speed setup section for setting a target engine rotation speed; load detection for detecting a hydraulic pump load; an assist output computation section for calculating an assist output to be generated by a motor generator in accordance with a rotation speed deviation ?N, which is the difference between an actual and target rotation speed, or in accordance with the hydraulic pump load; an absorption torque upper limit computation section for calculating an absorption torque upper limit value of the hydraulic pump; and an operation signal generation section for generating the operation signal to be output to a pump displacement adjustment device. When the rotation speed deviation ?N is equal to or more than a setting NC determined in accordance with the assist output value, the absorption torque upper limit computation section reduces the absorption torque upper limit value of the hydraulic pump from the calculated value.

Abstract: Provided is a hybrid construction machine together with a method for controlling that construction machine in a manner ensuring the operability of its combined operations regardless of fluctuations in the load on its work machine.

Abstract: A vehicle control system which can ensure high reliability, real-time processing, and expandability with a simplified ECU configuration and a low cost by backing up an error through coordination in the entire system without increasing a degree of redundancy of individual controllers beyond the least necessary level. The vehicle control system comprises a sensor controller for taking in sensor signals indicating a status variable of a vehicle and an operation amount applied from a driver, a command controller for generating a control target value based on the sensor signals taken in by the sensor controller, and an actuator controller for receiving the control target value from the command controller and operating an actuator to control the vehicle, those three controller being interconnected via a network.

Abstract: A vehicle control system which can ensure high reliability, real-time processing, and expandability with a simplified ECU configuration and a low cost by backing up an error through coordination in the entire system without increasing a degree of redundancy of individual controllers beyond the least necessary level. The vehicle control system comprises a sensor controller for taking in sensor signals indicating a status variable of a vehicle and an operation amount applied from a driver, a command controller for generating a control target value based on the sensor signals taken in by the sensor controller, and an actuator controller for receiving the control target value from the command controller and operating an actuator to control the vehicle, those three controller being interconnected via a network.

Abstract: A hydraulic working machine has an assist electric motor connected to an engine and a hydraulic pump. The emissions of air pollutants in the exhaust gas from the engine are minimized regardless of fluctuations in the load torque of the hydraulic pump. A specific revolution speed suitable for reducing the emissions of air pollutants is stored, and an engine is controlled using the specific revolution speed as a target revolution speed. The absorption torque of a hydraulic pump is subjected to high-pass filtering whereby a high-frequency component devoid of a trend component is obtained. Target assist torque is computed from the high-frequency component, and the assist electric motor is subjected to power running/generation control accordingly. A specific output torque range suitable for reducing the emissions of air pollutants is stored, and the target assist torque is corrected so that the trend component does not exceed the specific output torque range.

Abstract: The present invention includes a target rotation speed setup section (17) for setting a target rotation speed of an engine (1); load detection means (21) for detecting a load on a hydraulic pump (3); an assist output computation section (19) for calculating an assist output to be generated by a motor generator in accordance with a rotation speed deviation ?N, which is the difference between an actual rotation speed and the target rotation speed, or in accordance with the load on the hydraulic pump; an absorption torque upper limit computation section (23) for calculating an absorption torque upper limit value of the hydraulic pump (3); and an operation signal generation section (24) for generating the operation signal to be output to a pump displacement adjustment device (45).