JP5803874B2 - Hybrid work machine - Google Patents

Description

  The present invention relates to a hybrid work machine such as a construction machine or a civil engineering machine.

  Conventionally, as a hybrid work machine, there is one described in Japanese Patent Application Laid-Open No. 2005-163605 (Patent Document 1). This hybrid work machine is connected to the engine, a hydraulic pump driven by the engine, an assisting / regenerating motor / generator coupled to the engine and capable of powering and regeneration, and the motor / generator. Power storage device. Then, the electric power stored in this power storage device is supplied to the motor / generator etc. at an appropriate timing according to the state of the load of the hydraulic pump, and the drive of the hydraulic pump by the engine is appropriately assisted by the motor / generator. Like to do.

JP 2005-163605 A

  By the way, in the conventional hybrid work machine, the engine speed is controlled by a so-called droop characteristic in which the engine speed fluctuates depending on the load. When the load decreases, the engine speed increases, while the load increases. Then, the rotational speed of the engine is reduced. For this reason, an operator of the hybrid work machine can detect the increase / decrease change of the load based on the increase / decrease change of the rotational speed of the engine to improve the work efficiency.

  However, in the conventional hybrid work machine, when the regenerative energy is supplied from the power storage device to the motor / generator to assist the engine drive, the fuel injection amount can be reduced as shown in FIG. There was a problem that the rotational speed increased.

  In addition, since the above conventional hybrid work machine has a power storage device, the regenerative energy is temporarily stored to level out and prevent a sudden change in the assist operation, thereby causing a sudden change in engine load. Can be prevented, and a sufficient fuel reduction effect can be exhibited. However, there are problems such as high cost and a large vehicle body.

  Therefore, the problem of the present invention is that, in a hybrid work machine having no capacitor, even if it is immediately used for assisting operation without leveling the regenerative energy, the rotational speed of the engine can be made substantially constant and short. An object of the present invention is to provide a hybrid work machine that can sufficiently reduce the fuel consumption of an engine even during time-assisted operation.

In order to solve the above problems, the hybrid work machine of the present invention is
Engine,
A rotational speed detector for detecting the rotational speed of the engine ;
An engine control unit for controlling the above SL engine,
An assist motor that assists in driving the engine;
Regenerative energy from the regenerative device is used for assist operation by driving the assist motor without any means for temporarily storing energy, and energy regeneration control for inputting the amount of regenerative energy to the engine control unit With the device ,
The engine control unit
A rotation speed setting unit for setting a target rotation speed of the engine;
A first addition point for calculating a deviation between the target engine speed output from the engine speed setting unit and the current engine speed detected by the engine speed detector;
A second summing point for calculating an operation amount based on the deviation output from the first summing point and the amount of the regenerative energy input by the energy regeneration control device;
Have
The engine is controlled based on the operation amount output from the second addition point .

  According to the hybrid working machine having the above-described configuration, the regenerative energy from the regenerative device is used for assist operation by driving the assist motor without any means for temporarily storing energy, thereby increasing or decreasing the assist force. To do. The engine control unit determines an operation amount based on a deviation between the current engine speed detected by the engine speed detector and the target engine speed. Then, the manipulated variable is corrected by the energy regeneration control device so as to decrease in accordance with the increase in the amount of regenerative energy from the regeneration device. As described above, the assist motor is driven to increase or decrease the assist force in accordance with the amount of regenerative energy from the regenerative device, and at the same time, the operation amount is corrected by feedforward control. Therefore, in a hybrid work machine that does not have a capacitor, even if the regenerative energy is leveled and used for the assist operation immediately, the energy regenerative control device adds an additional point according to the amount of regenerative energy. Alternatively, since the amount of regenerative energy is input to the rotational speed setting unit and the manipulated variable is corrected by feedforward control, the engine rotational speed can be made substantially constant and the assist operation can be performed for a short time. There is no delay in control, and the fuel consumption of the engine can be sufficiently reduced.

In the hybrid work machine of one embodiment,
The operation amount is a fuel injection amount to the engine.

  According to the embodiment, the fuel injection amount to the engine, which is the operation amount, is corrected by the energy regeneration control device according to the amount of regenerative energy from the regeneration device. Therefore, even if the assist operation is performed, the rotational speed of the engine can be made substantially constant, and the fuel consumption of the engine can be reduced even by the assist operation for a short time.

In the hybrid work machine of one embodiment,
The operation amount is a torque command to the engine.

  According to the embodiment, the torque command to the engine, which is the operation amount, is corrected by the energy regeneration control device according to the amount of regenerative energy recovered from the regeneration device. Therefore, even if the assist operation is performed, the rotational speed of the engine can be made substantially constant, and the fuel consumption of the engine can be reduced even by the assist operation for a short time.

In the hybrid work machine of one embodiment,
Engine,
A rotational speed detector for detecting the rotational speed of the engine;
An engine control unit for controlling the engine;
An assist motor that assists in driving the engine;
Regenerative energy from the regenerative device is used for assist operation by driving the assist motor without any means for temporarily storing energy, and energy regeneration control for inputting the amount of regenerative energy to the engine control unit Equipment and
With
The engine control unit
A rotation speed setting unit for setting a target rotation speed of the engine;
A first addition point for calculating a deviation based on the target rotational speed of the engine output from the rotational speed setting unit and the amount of the regenerative energy input by the energy regeneration control device;
A second summing point for calculating an operation amount based on the deviation output from the first summing point and the current rotational speed of the engine detected by the rotational speed detector;
Have
The engine is controlled based on the operation amount output from the second addition point .

  According to the embodiment, the rotational speed command to the engine, which is the operation amount, is corrected by the energy regeneration control device according to the amount of regenerative energy recovered from the regeneration device. Therefore, even if the assist operation is performed, the rotational speed of the engine can be made substantially constant, and the fuel consumption of the engine can be reduced even by the assist operation for a short time.

In the hybrid work machine of one embodiment,
Engine,
A rotational speed detector for detecting the rotational speed of the engine;
An engine control unit for controlling the engine;
An assist motor that assists in driving the engine;
The regenerative energy from the regenerative unit is used for assist operation by driving the assist motor without any means for temporarily storing energy, and has a function of correcting the rotation speed command of the work machine controller. And an energy regeneration control device for inputting a corrected rotational speed command to the engine control unit,
With
The engine control unit
A rotation speed setting unit that sets a target rotation speed of the engine based on a corrected rotation speed command input by the energy regeneration control device;
An addition point for calculating an operation amount based on the target rotational speed of the engine output from the rotational speed setting unit and the current rotational speed of the engine detected by the rotational speed detector;
Have
The engine is controlled based on the operation amount output from the addition point .

  According to the embodiment, the rotation speed command output from the work machine controller to the engine control unit is corrected by the energy regeneration control device according to the amount of regenerative energy recovered from the regeneration device. Therefore, even if the assist operation is performed, the rotational speed of the engine can be made substantially constant, and the fuel consumption of the engine can be reduced even by the assist operation for a short time.

  Moreover, according to the said embodiment, it is realizable, without changing the engine control part of a conventional form.

  According to the hybrid type working machine of the present invention, the engine speed can be made substantially constant even if it is immediately used for assisting operation without leveling the regenerative energy in the hybrid type working machine having no electric storage device. In addition, the fuel consumption of the engine can be sufficiently reduced even with a short assist operation.

It is a control block diagram of the hybrid type working machine of one Embodiment of this invention. It is a figure which shows the characteristic of the fuel injection quantity with respect to the rotational speed of the engine of the said hybrid type working machine. (A), (B), (C) is explanatory drawing explaining the relationship between the amount of the assist torque by the assist motor of the said hybrid type work machine, the rotational speed of an engine, and the amount of fuel injection. It is a control block diagram of other embodiments of the above-mentioned hybrid type work machine. It is a control block diagram of other embodiments of the above-mentioned hybrid type work machine. It is a control block diagram of other embodiments of the above-mentioned hybrid type work machine. It is a figure which shows the characteristic of the fuel injection quantity with respect to the rotational speed of the engine of the conventional hybrid type work machine.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a hybrid work machine of the present invention will be described in detail with reference to illustrated embodiments.

  As shown in the control block diagram of FIG. 1, the hybrid work machine of this embodiment includes an engine 11, a pulse generator 13 as an example of a rotational speed detector that detects the rotational speed of the engine 11, and the engine 11, an assist motor 21 that assists in driving the engine 11, an assist controller 22 that controls the assist motor 21, a regeneration device 41, and regeneration energy from the regeneration device 41. The energy regeneration control device 31 is provided.

  The regenerative device 41 includes a hydraulic motor (not shown) and a generator (not shown) driven by the hydraulic motor, converts the pressure energy of hydraulic oil into electrical energy, and outputs the regenerative energy to the energy regeneration control device 31. To do.

  The energy regeneration control device 31 supplies the regenerative energy from the regeneration device 41 to the assist motor 21 via the assist controller 22 to assist in driving the engine 11.

  The assist controller 22 receives a signal representing the amount of regenerative energy from the energy regenerative control device 31 through communication, controls the amount of power supplied to the assist motor 21 according to the amount of regenerative energy, and assists the assist controller 22. The assist force by the motor 21 is controlled.

  On the other hand, the engine control unit 12 includes a target engine speed setting unit 15, a PID (proportional integral derivative) control unit 16, a converter 17, and addition points 101 and 102.

  When the target engine speed is set, the target engine speed setting unit 15 outputs a signal representing the target engine speed to the addition point 101.

  A signal representing the current rotational speed of the engine 11 is also input from the pulse generator 13 to the addition point 101. The addition point 101 subtracts a signal representing the current rotational speed of the engine 11 from a signal representing the target engine rotational speed, and outputs a deviation signal representing these deviations to the PID control unit 16.

  The PID control unit 16 performs a PID (proportional integral derivative) control operation on the deviation signal, and calculates an operation amount for the rotational speed of the engine 11 to become the target engine rotational speed. This operation amount is a signal representing the fuel injection amount to the engine 11 that increases or decreases according to the magnitude of the deviation. Then, the PID control unit 16 outputs a fuel injection amount signal indicating the fuel injection amount to the engine 11 to the addition point 102.

  On the other hand, the energy regeneration control device 31 outputs a signal representing the amount of regenerative energy to the assist controller 22 and also to the converter 17. The converter 17 converts the regenerative energy amount into a fuel injection amount correction amount to the engine 11 corresponding to the regenerative energy amount, and outputs the fuel correction amount signal to the addition point 102.

  The addition point 102 is a corrected fuel injection amount obtained by correcting the fuel injection amount signal by subtracting the fuel correction amount signal from the converter 17 from the fuel injection amount signal that is the operation amount from the PID control unit 16. A signal is output to the engine 11.

  In this way, the energy regeneration control device 31 uses the regeneration energy from the regeneration device 41 for assisting operation by driving the assist motor 21 without any means for temporarily storing energy, so that the engine At the same time, the fuel injection amount signal from the PID control 16 is corrected by the fuel correction amount signal converted by the converter 17. That is, the energy regeneration control device 31 corrects the fuel injection amount signal by feedforward control according to the amount of regenerative energy while using the regenerative energy for assisting the driving of the engine 11.

  The output of the engine 11 and the output of the assist motor 21 are added together at an addition point 51 and transmitted to the load 61.

  FIG. 2 shows the fuel injection amount characteristic of the engine 11 with respect to the rotational speed of the engine 11. As shown in FIG. 2, when the assist operation is performed, the fuel injection amount characteristic is shifted to the fuel injection amount characteristic indicated by the imaginary line in FIG. 2, while maintaining the rotational speed of the engine 11 substantially constant. 11 can be reduced.

  FIG. 3 shows the relationship between the amount of assist torque by the assist motor 21, the rotational speed of the engine 11, and the fuel injection amount. Even in a short assist operation as shown in FIG. 3 (A), as shown in FIG. 3 (B), while maintaining the rotational speed of the engine 11 substantially constant, and as shown in FIG. 3 (C), By the feedforward control, there is no delay in the control, and the fuel injection amount to the engine 11 can be sufficiently reduced.

  Moreover, even if it does not have an electrical storage device, the drive of the engine 11 can be assisted immediately by utilizing for an assist operation | movement, without equalizing regenerative energy. For this reason, the whole hybrid work machine can be reduced in size, and the manufacturing cost can also be reduced.

  FIG. 4 is a control block diagram of a hybrid work machine according to another embodiment. 4, the same components as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and the description thereof will be omitted. Different configurations will be described below.

  As shown in FIG. 4, the hybrid work machine of the above embodiment includes a fuel injection amount calculation unit 18 between the addition point 102 and the engine 11.

  In the hybrid work machine of the embodiment, the operation amount of the PID control unit 16 is a torque command signal that represents a torque command for the engine 11. The converter 17 converts the torque correction amount of the engine 11 corresponding to the regenerative energy amount, and outputs the torque correction amount signal to the addition point 102.

  The addition point 102 is obtained by subtracting the torque correction amount signal from the converter 17 from the torque command signal from the PID control unit 16, and using the corrected torque command signal obtained by correcting the torque command signal as the fuel injection amount calculation unit. 18 is output.

  The fuel injection amount calculation unit 18 performs a fuel injection amount calculation to the engine 11 with respect to the corrected torque command signal, and calculates a fuel injection amount for the torque of the engine 11 to be a corrected torque. A fuel injection amount signal representing the fuel injection amount is output to the engine 11.

  Instead of the converter 17 outputting the torque correction amount signal to the addition point 102, the assist controller 22 adds a torque correction amount signal representing the torque of the engine 11 corresponding to the regenerative energy amount. May be output. In this way, even if the converter 17 is not provided, the rotational speed of the engine 11 can be made substantially constant even when the torque command is corrected at the addition point 102 and the assist operation is performed. Even in the assist operation, the fuel consumption of the engine 11 can be reduced.

  FIG. 5 is a control block diagram of a hybrid work machine according to another embodiment. In FIG. 5, the same components as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and the description thereof will be omitted. Different configurations will be described below.

  As shown in FIG. 5, the hybrid work machine of the above embodiment includes a fuel injection amount calculation unit 18 between the P control unit 16 ′ and the engine 11. Further, an addition point 102 is provided between the target engine speed setting unit 15 and the addition point 101.

  In the hybrid work machine of the above embodiment, the converter 17 converts the rotational speed correction amount of the engine 11 corresponding to the regenerative energy amount and outputs the engine rotational speed correction value signal to the addition point 102. .

  The addition point 102 is a signal representing the target engine rotational speed by subtracting the engine rotational speed correction value signal from the converter 17 from the signal representing the target engine rotational speed from the target engine rotational speed setting unit 15. The corrected target engine rotation speed signal corrected by the above is output to the addition point 101.

  The P control unit 16 ′ performs P (proportional) control calculation on the calculation result of the addition point 101, and calculates an operation amount for the rotation speed of the engine 11 to be the target engine rotation speed. This manipulated variable is a target torque command signal that represents the target torque of the engine 11 that increases or decreases according to the magnitude of the deviation. The P control unit 16 ′ outputs a target torque command signal indicating the target torque of the engine 11 to the fuel injection amount calculation unit 18.

  The fuel injection amount calculation unit 18 calculates a fuel injection amount for the engine 11 to become a target torque by performing a fuel injection amount calculation to the engine 11 with respect to the target torque command signal. A signal representing the fuel injection amount is output to the engine 11.

  In the above embodiment, the P control unit 16 ′ performs P (proportional) control calculation. However, in the present invention, other arbitrary function calculation may be performed.

  FIG. 6 is a control block diagram of a hybrid work machine according to another embodiment. In FIG. 6, the same components as those shown in FIG. 1 are denoted by the same reference numerals as those of the components in FIG.

  As shown in FIG. 6, in the hybrid work machine of the above embodiment, the energy regeneration control device 31 has a function of correcting the rotation speed command value of the work machine controller 71. The energy regeneration control device 31 outputs the corrected rotational speed command value to the target engine rotational speed setting unit 15.

  In the hybrid work machine of the above embodiment, the energy regeneration control device 31 adds the correction amount of the rotation speed command value of the work machine controller 71 corresponding to the regenerative energy amount to the rotation speed command value of the work machine controller 71, The corrected rotational speed command is output to the target engine rotational speed setting unit 15.

  The addition point 101 subtracts the actual engine rotation speed from the target engine rotation speed from the target engine rotation speed setting unit 15 and outputs the result to the P control unit 16 ′.

  The P control unit 16 ′ performs P (proportional) control calculation on the calculation result of the addition point 101, and calculates an operation amount for the rotation speed of the engine 11 to be the target engine rotation speed. This manipulated variable is a target torque command signal that represents the target torque of the engine 11 that increases or decreases according to the magnitude of the deviation. The P control unit 16 ′ outputs a target torque command signal indicating the target torque of the engine 11 to the fuel injection amount calculation unit 18.

  The fuel injection amount calculation unit 18 calculates a fuel injection amount for the engine 11 to become a target torque by performing a fuel injection amount calculation to the engine 11 with respect to the target torque command signal. A signal representing the fuel injection amount is output to the engine 11.

  In this embodiment, in the engine control unit 12 indicated by a broken line in FIG. 6, the fuel injection amount calculation unit 18 does not change from the conventional configuration, the fuel injection amount to the engine 11 with respect to the target torque command signal. An arithmetic operation is performed to calculate a fuel injection amount for the torque of the engine 11 to become the target torque, and a signal representing this fuel injection amount is output to the engine 11.

  In the above embodiment, the P control unit 16 ′ performs P (proportional) control calculation. However, in the present invention, other arbitrary function calculation may be performed.

DESCRIPTION OF SYMBOLS 11 Engine 12 Engine control part 13 Pulse generator 21 Assist motor 31 Energy regeneration control apparatus 41 Regeneration apparatus

Claims (5)

An engine (11);
A rotational speed detector (13) for detecting the rotational speed of the engine (11) ;
The engine control unit for controlling the upper SL engine (11) and (12),
An assist motor (21) that assists in driving the engine (11);
The regenerative energy from the regenerative device (41) is used for assist operation by driving the assist motor (21) without any means for temporarily storing energy, and the regenerative energy is supplied to the engine control unit (12 ). An energy regeneration control device (31) for inputting an amount of energy ,
The engine control unit (12)
A rotational speed setting unit (15) for setting a target rotational speed of the engine (11);
A deviation between the target rotational speed of the engine (11) output from the rotational speed setting unit (15) and the current rotational speed of the engine (11) detected by the rotational speed detector (13) is calculated. , A first addition point (101),
A second addition point (102) that calculates an operation amount based on the deviation output from the first addition point (101) and the amount of the regenerative energy input by the energy regeneration control device (31). )When
Have
A hybrid work machine that controls the engine (11) based on the operation amount output from the second addition point (102) . The hybrid work machine according to claim 1,
The hybrid working machine, wherein the operation amount is a fuel injection amount to the engine (11). The hybrid work machine according to claim 1,
The hybrid working machine, wherein the operation amount is a torque command to the engine (11). An engine (11);
A rotational speed detector (13) for detecting the rotational speed of the engine (11);
An engine control unit (12) for controlling the engine (11);
An assist motor (21) that assists in driving the engine (11);
The regenerative energy from the regenerative device (41) is used for assist operation by driving the assist motor (21) without any means for temporarily storing energy, and the regenerative energy is supplied to the engine control unit (12). An energy regeneration control device (31) for inputting an amount of energy;
With
The engine control unit (12)
A rotational speed setting unit (15) for setting a target rotational speed of the engine (11);
A deviation is calculated based on the target rotational speed of the engine (11) output from the rotational speed setting unit (15) and the amount of the regenerative energy input by the energy regeneration control device (31). In addition point (102),
An operation amount is calculated based on the deviation output from the first addition point (102) and the current rotational speed of the engine (11) detected by the rotational speed detector (13); Addition point (101) and
Have
A hybrid work machine that controls the engine (11) based on the operation amount output from the second addition point (101) . An engine (11);
A rotational speed detector (13) for detecting the rotational speed of the engine (11);
An engine control unit (12) for controlling the engine (11);
An assist motor (21) that assists in driving the engine (11);
The regenerative energy from the regenerative device (41) is used for assist operation by driving the assist motor (21) without any means for temporarily storing energy, and the rotational speed command of the work machine controller (71). An energy regeneration control device (31) for inputting a corrected rotational speed command to the engine control unit (12).
With
The engine control unit (12)
A rotational speed setting unit (15) for setting a target rotational speed of the engine (11) based on a corrected rotational speed command input by the energy regeneration control device (31);
An operation amount based on the target rotational speed of the engine (11) output from the rotational speed setting unit (15) and the current rotational speed of the engine (11) detected by the rotational speed detector (13). To calculate the addition point (101) and
Have
A hybrid work machine that controls the engine (11) based on the operation amount output from the addition point (101) .

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