KR101422817B1 - The Control Method of Hybrid Excavators - Google Patents

Abstract

A method of controlling a speed ratio of a hybrid excavator according to the present invention is a hybrid excavator in which a swivel portion is independently driven by a swivel motor, comprising a first step of deriving a swivel speed reference value by a swivel speed reference value arithmetic logic using a swiveling lever operation signal A second step of extracting respective turning speed adjustment values by a turning speed command adjusting value calculating logic using a boom lever operating signal, a lever lever operating signal, a bucket lever operating signal, and a traveling pedal operating signal, A controller that calculates the final turning speed command value using the turning speed reference value calculated by the arithmetic logic and the turning speed adjusting value extracted from the turning speed command adjusting value calculating logic and then outputs the calculated final turning speed command value to the swing motor driving inverter to perform the swing speed control 3, and the speed control of the swinging motor, and the pump flow control command value calculation logic To perform the pump flow rate control, and a fourth step of adjusting the speed ratio of the entire work apparatus.

Description

[0001] The present invention relates to a hybrid excavator,

The present invention relates to a hybrid excavator. More particularly, the present invention relates to a hybrid excavator, in which a speed ratio of a hybrid excavator capable of adjusting a speed ratio of an excavator working device for controlling the operation speed of each work device, And a control method.

The operation of the conventional hydraulic excavator working apparatus is a structure in which a flow rate discharged from two main pumps is divided into boom, arm, bucket, and hydraulic actuators (hydraulic cylinders and hydraulic motors) for traveling and turning operations, The speed ratio of the work machine is controlled mechanically and hydraulically by the lever manipulation amount for the operation of each working device and the excavator main control valve (MCV).

Unlike a hydraulic excavator, a general system of a hybrid excavator is composed of two main pumps, a hydraulic system for supplying the flow quantity necessary for boom, arm, bucket and running operation through the MCV, and an independent In electrical system.

Such a swing-independent system configuration may impose an appropriate working device speed ratio at the time of simultaneous operation of other working devices including turning, which may increase the operation burden on the driver for the combined operation. Therefore, it is necessary to artificially adjust the speed ratio of the working device in order to perform an effective operation in the complex operation including the turning.

In addition, when the flow rate of the main pump is not adjusted in consideration of the energy used by the swing motor for the swing operation, unnecessary power consumption may be caused.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a hydraulic excavator which can control the rotating speed of a swing motor in consideration of operating conditions of other working devices, By controlling the flow rate of the main pump supplied to the other working device by using the resultant rotational speed of the actual rotating electric motor, an appropriate speed ratio for the complex operation is implemented so as to perform an effective complex operation, thereby reducing the burden on the driver A control method capable of reducing unnecessary power consumption and a speed ratio control method of a hybrid excavator capable of improving work efficiency and reducing fuel consumption by configuring a driver so that a limit value for a work speed can be set in advance according to a work situation The purpose is to provide.

According to a first aspect of the present invention, there is provided a hybrid excavator in which a swing section is independently driven by a swing motor, comprising: a first step of deriving a swing speed reference value by a swing speed reference value arithmetic logic using a swing lever operating signal; A second step of extracting respective turning speed adjustment values by a turning speed command adjusting value calculating logic by using a lever operating signal, a lever lever operating signal, a bucket lever operating signal, and a traveling pedal operating signal, A third step of calculating the final turning speed command value using the turning speed reference value calculated by the turning speed reference value calculating circuit and the turning speed adjusting value extracted from the turning speed instruction adjusting value calculating logic and then outputting the final turning speed command value to the inverter for driving the turning motor, And pump flow rate control command value calculation logic at the same time as the swing motor speed control, Performing a control to, it characterized in that it comprises a fourth step of adjusting the speed ratio of the entire work apparatus.

Here, the second step is configured by logic having different adjustment values according to the respective operation signals. When two or more operations of the other operation apparatuses occur at the same time, the minimum value of each extracted adjustment value is taken, To obtain the final adjustment value.

The fourth step may include calculating a discharge flow rate Q_supply of the main pump by using the main pump discharge pressure and the pump flow rate control pilot pressure and calculating the discharge flow rate Q_supply using the actual rotational speed of the swing motor And calculating a turning flow rate Q_swing in a virtual manner.

In the fourth step, it is preferable to calculate the flow rate required for the revolving hydraulic motor assuming that the virtual turning amount required flow rate Q_swing is configured as the hydraulic system for the swing part as in the conventional hydraulic excavator.

In the fourth step, it is preferable to calculate the flow rate control command value Q_desired of the main pump 9 using the calculated discharge flow rate Q_supply and the turning flow rate Q_swing. In the fourth step, Q_desired = Q_supply - (Q_factor * Q_swing) is used as a command value (Q_desired) operation, and Q_factor is preferably applied as a value for maintaining a working device speed ratio.

In addition, in the fourth step, the driver can directly select the pump flow rate limit value. In the fourth step, the calculated pump flow rate control command value is compared with the pump flow rate limit value directly selected by the driver, The flow rate may be discharged.

INDUSTRIAL APPLICABILITY As described above, the present invention can reduce the operation burden on the driver caused by the deterioration of the operability due to the unbalance of the working device speed, and further contribute to the improvement of the working efficiency and the fuel efficiency improvement.

1 is a schematic system configuration diagram of a hybrid excavator in a speed ratio control method of a hybrid excavator according to the present invention.
2 is a control block diagram of a speed ratio control method of a hybrid excavator according to the present invention.
3 is a diagram illustrating a method of extracting a reference speed value according to an operation signal in a speed ratio control method of a hybrid excavator according to the present invention.
4 is a view illustrating a method of extracting a swing speed adjustment value according to an operation of the swing external operation device in the speed ratio control method of a hybrid excavator according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the present invention, the defined terms are defined in consideration of the function of the present invention, and should not be understood in a limiting sense of the technical elements of the present invention.

1, the hybrid excavator includes an engine 11 as a power source, a hydraulic pump 9, a pump regulator 8, an engine assist motor 7, and a main control valve 10, As shown in Fig. The running operation is performed using the hydraulic energy supplied from the hydraulic pump 9 and the turning operation is performed by the swing motor 6 using the electric energy of the power storage device 12 to which the inverter 5 is connected do. Here, a controller (controller) 1 for controlling the speed of the combined hybrid excavator operation is provided.

Here, the controller 1 includes a revolution speed reference value calculation logic 1-1, a revolution speed command adjustment value calculation logic 1-2, and a pump flow rate control instruction value calculation logic 1-3. That is, the present invention is divided into a revolving speed control section and a pump flow control section.

The method of controlling the speed ratio of the hybrid excavator of the present invention will be described below in order.

First, in the first step, in the hybrid excavator in which the swing section is independently driven by the swing motor 6, the swing lever reference signal computing logic derives the swing reference value using the swing lever operation signal 3-1.

Next, the second step uses the boom lever control signal 3-2, the lever control signal 3-3, the bucket lever control signal 3-4 and the pedal control signal 3-5, The respective revolution speed adjustment values are extracted by the revolution speed command adjustment value calculation logic.

Here, the second step consists of logic having different adjustment values in accordance with the respective operation signals. When two or more operations occur simultaneously, the minimum value of each extracted adjustment value is taken, and a predetermined adjustment value It is preferable to take the final adjustment value by weighting.

Next, in the third step, the final turning speed command value is calculated using the turning speed reference value calculated by the turning speed reference value calculating logic and the turning speed adjusting value extracted from the turning speed command adjusting value calculating logic. Thereafter, the electric power is outputted to the inverter (5) for driving the swing motor (6) to perform the revolution speed control.

Next, in the fourth step, the pump flow rate control is performed simultaneously with the speed control of the swing motor 6 using the pump flow rate control command value calculation logic. The speed ratio of the overall working device is then adjusted.

More specifically, in the fourth step, the discharge flow rate Q_supply of the main pump 9 is calculated using the discharge pressure 4-1 of the hydraulic pump 9 and the pump flow rate adjustment pilot pressure 4-2 .

Then, it includes a step of virtually calculating the required turning amount Q_swing by using the actual rotating speed of the rotating electric motor 6, which is the result of the speed control of the turning motor 6.

Here, in the fourth step, the virtual flow amount Q_swing required for turning can be calculated as a flow amount required for the swing hydraulic motor, assuming that the swing portion is constituted by a hydraulic system like a conventional hydraulic excavator.

To this end, the flow rate control command value Q_desired of the hydraulic pump 9 is calculated using the discharge flow rate Q_supply of the hydraulic pump 9 calculated and the flow rate Q_swing required for turning. The command value Q_desired calculation Q_desired = Q_supply - (Q_factor * Q_swing) can be used. Here, Q_factor is a gain value for maintaining an appropriate working device speed ratio.

In addition, the Q_desired value calculated through the above equation is compared with the flow restriction value for the step value of the pump flow restriction mode selected by the driver, thereby calculating the final pump flow control command value so as to discharge a small amount of flow.

Then, the calculated command value is outputted to a flow control solenoid valve MCV (main control valve) of the pump regulator 8 which is a solenoid valve for flow control. Ultimately, by maintaining an appropriate speed ratio between the turning and the other working devices, the improvement of the working efficiency and the further improvement of the fuel economy by the smooth complex operation implementation are achieved.

Meanwhile, in the fourth step, the driver can directly select the pump flow rate limit value, and the calculated pump flow rate control command value can be compared with the pump flow rate limit selected directly by the driver so that the smallest flow rate can be finally discharged.

That is, the maximum discharge flow rate of the hydraulic pump 9 is limited in several steps by using the pump flow rate restriction mode selection device 2 separately from the flow rate control command value of the hydraulic pump 9 calculated in the fourth step Can be configured. This is to allow the driver to select the fuel economy priority or the work economy priority according to the current working characteristics and environment.

The pump flow rate restriction mode selection device 2 may be configured to select a mode on the equipment monitor or use a separate selection switch.

In the mode configuration, the larger the flow restriction value corresponding to the step selected by the driver, the more the workability becomes, and the smaller the flow restriction value becomes, the more fuel efficiency becomes.

As a result, the present invention can reduce the operation burden on the driver caused by the deterioration of the operability due to the unbalance of the working device speed, and further contribute to the improvement of the working efficiency and the fuel efficiency improvement.

The above description of the speed ratio control method of the hybrid excavator according to the present invention has been made with reference to the accompanying drawings, which illustrate the best preferred embodiment of the present invention but do not limit the present invention.

Accordingly, it is a matter of course that various modifications and variations of the present invention are possible without departing from the scope of the present invention. And are included in the technical scope of the present invention.

1: Controller
2: Pump flow limitation mode selection device
3-1: Turning lever operation signal
3-2: Boom lever operation signal
3-3: Arm lever operation signal
3-4: Bucket lever operation signal
3-5: Pedal operation signal
4-1: Main pump discharge pressure
4-2: Pump flow control pilot pressure
5: Inverter
6: Swinging motor
7: Engine assist motor
8: Pump regulator
9: Hydraulic pump
10: MCV (Main Control Valve)
11: Engine
12: Power storage device

Claims (8)

A hybrid excavator in which a swing section is independently driven by a swing motor,
A first step of deriving a turning speed reference value by a turning speed reference value calculating logic using a turning lever operating signal;
A second step of extracting respective turning speed adjustment values by a turning speed command adjusting value calculating logic by using a boom lever operating signal, a lever lever operating signal, a bucket lever operating signal, and a traveling pedal operating signal;
The final turning speed command value is calculated using the turning speed reference value calculated by the turning speed reference value calculating logic and the turning speed adjusting value extracted from the turning speed command adjusting value calculating logic and then outputted to the inverter for driving the turning motor to perform the turning speed control A third step performed; And
And a fourth step of controlling the speed ratio of the overall working device by performing the pump flow rate control using the pump flow rate control command value calculation logic at the same time as the swing motor speed control . The method according to claim 1,
Wherein the second step is constituted by logic whose adjustment value is different according to each operation signal,
Wherein when the two or more different operations of the other work apparatuses occur simultaneously, the minimum value of each of the extracted adjustment values is taken and the final adjustment value is taken by weighting a predetermined adjustment value. The method according to claim 1,
Calculating a discharge flow rate Q_supply of the main pump using the main pump discharge pressure and the pump flow rate control pilot pressure; And
And calculating a required turning flow rate (Q_swing) by virtually using the actual turning motor rotation speed which is a result of the turning motor speed control. The method of claim 3,
In the fourth step, the virtual flow rate required for turning (Q_swing) is calculated on the assumption that the swivel part is constituted of the hydraulic system as in the conventional hydraulic excavator, and the flow rate required for the swiveling hydraulic motor is calculated Way. 5. The method of claim 4,
Wherein the fourth step calculates the flow rate control command value Q_desired of the main pump 9 using the calculated discharge flow rate Q_supply and the turning flow rate Q_swing of the main pump 9, Uncontrolled method. 6. The method of claim 5,
In the fourth step, Q_desired = Q_supply - (Q_factor * Q_swing) is used as the command value (Q_desired)
And Q_factor is applied as a value for maintaining a working device speed ratio. The method according to claim 1,
Wherein in the fourth step, the driver can directly select the pump flow rate limit value. 8. The method of claim 7,
Wherein in the fourth step, the computed pump flow rate control command value is compared with a pump flow rate limit value directly selected by the driver, so that a small flow rate is finally discharged.

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