KR19990005279A - Automatic Gain Tuning Device and Method - Google Patents

Abstract

The present invention relates to an automatic gain tuning apparatus and method, and more particularly to an automatic gain tuning apparatus and method, in which, in current operating conditions of a heavy equipment such as an excavator, To an automatic gain tuning apparatus and method for automatically tuning a gain of an adjustment amount of a swash plate angle. An automatic gain tuning device according to a preferred embodiment of the present invention is an automatic gain tuning device for automatically tuning the gain of an engine speed control value of a heavy equipment engine or an adjustment amount of a swash plate angle of a hydraulic pump, An input means for inputting a condition, a storage means in which an operating condition when the heavy equipment operates in an optimal state is set in advance, an operating condition from the input means and an operating condition set in advance to the storage means, And a display means for displaying a gain obtained from the calculation means.

Description

Automatic Gain Tuning Device and Method

The present invention relates to an automatic gain tuning apparatus and method, and more particularly to an automatic gain tuning apparatus and method, in which, in current operating conditions of a heavy equipment such as an excavator, To an automatic gain tuning apparatus and method for automatically tuning a gain of an adjustment amount of a swash plate angle.

In a heavy equipment such as an excavator, the control of the engine and the hydraulic pump adjusts the number of revolutions of the engine by adjusting the throttle valve of the engine according to the conditions of the work, for example, The maximum discharge flow rate that the pump can discharge is set and used. This will be described in more detail with reference to FIGS. 1 and 2. FIG.

Fig. 1 schematically shows the relationship between the torque of the engine of the heavy equipment and the number of revolutions. Fig. 2 schematically shows the relationship between the discharge pressure and the flow rate of the hydraulic pump of the heavy equipment. Since the used horsepower of the pump driven by the engine must be smaller than the engine output horsepower, the conditions under which the engine is operated without being subjected to the load,

TN ≥ PQ

. Accordingly, as shown in FIG. 4, the swash plate angle of the hydraulic pump is adjusted to move the PQ line so that the pump operates below the engine horsepower curve at the set engine speed. That is, the PQ line of the pump is limited by limiting the angle at which the swash plate angle of the pump can be moved to the maximum, and the maximum discharge amount is limited by moving the PQ line of the pump to a maximum efficiency below the set engine horsepower curve.

Due to aging of the engine, the operating characteristics of the engine and the pump are changed. In this case, the torque generated at the set engine speed is reduced. Therefore, since the initial engine horsepower curve is lowered, a load is applied to the engine and the engine stalls.

In view of such problems, the engine speed and the operating conditions of the pump are set at an early stage with considerable margin before shipment of the actual heavy equipment. For this purpose, conventionally, in order to set the gain according to the specific control algorithm so as to control the engine and the pump in accordance with the working conditions, various tests are performed before the shipment of the equipment, Respectively. However, it takes a lot of time and manpower to obtain the test data for setting the appropriate gain. In addition, the gain set in this way is somewhat different from equipment to equipment, so it is not suitable for other equipment of the same model of the same model. Further, if the characteristics of the engine and the pump are changed due to the equipment being aged, the gain set properly at the time of shipment of the equipment becomes ineffective.

Therefore, it is an object of the present invention to automatically adjust the rotation speed adjustment value of the engine or the adjustment amount of the swash plate angle of the hydraulic pump so that the heavy equipment is operated at the optimal performance under the current operating condition of the heavy equipment, And to provide an automatic gain tuning apparatus and method for tuning the same.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a diagram schematically showing a relationship between a torque and a revolution number of an engine of a heavy equipment; Fig.

2 is a diagram schematically showing a relationship between a discharge pressure and a flow rate of a hydraulic pump of a heavy equipment;

3 is a block diagram showing an embodiment of an automatic gain tuning device according to the present invention.

4 is a diagram showing an embodiment in which an automatic gain tuning device according to the present invention is applied to a heavy equipment.

Description of reference numerals used in the main parts of the drawings

10: input means 11: controller

12: engine speed detecting means 14: discharge flow rate detecting means

16: Discharge pressure detecting means 20: Storage means

30: computing means 40: display means

According to another aspect of the present invention, there is provided an automatic gain tuning apparatus for automatically tuning a gain of an engine speed control value of a heavy equipment engine or an adjustment amount of a swash plate angle of a hydraulic pump An input means for inputting a current operating condition of the heavy equipment, a storage means for presetting an operating condition when the heavy equipment is operated in an optimal state, an operation condition setting means for setting an operating condition from the input means, A calculation means for obtaining a gain by comparing the conditions, and a display means for displaying a gain obtained from the calculation means.

Another feature of the automatic gain tuning device according to the preferred embodiment of the present invention is that the input means receives input of the heavy equipment operating condition from at least one of the controller and the sensor in the heavy equipment.

Another feature of the automatic gain tuning device according to the preferred embodiment of the present invention is that at least one of the serial, parallel, and network is used for data input from the input means and the controller.

According to another aspect of the present invention, there is provided an automatic gain tuning method for automatically tuning a gain of an engine speed control value of a heavy equipment or an adjustment amount of a swash plate angle of a hydraulic pump, Inputting a current operating condition of the heavy equipment, computing a gain in comparison with a preset operating condition when the heavy equipment operates in an optimal state, and displaying the calculated gain.

Another feature of the automatic gain tuning method according to the preferred embodiment of the present invention is to calculate the gain to fix the rotational speed of the engine and change the maximum swash angle of the hydraulic pump in the calculating step.

Another feature of the automatic gain tuning method according to the preferred embodiment of the present invention is to calculate the gain to fix the maximum swash plate angle of the hydraulic pump and change the engine speed in the calculating step.

Hereinafter, the features of the automatic gain tuning device according to the preferred embodiment of the present invention will be described in detail with reference to FIG. 3 and FIG. FIG. 3 shows an embodiment of the automatic gain tuning device according to the present invention, and FIG. 4 shows an embodiment in which the automatic gain tuning device according to the present invention is applied to a heavy equipment. The automatic gain tuning device comprises input means (10) for detecting the current operating condition of the heavy equipment, storage means (20) in which the operating condition when the heavy equipment is operating optimally is set in advance, (30) for obtaining a gain by comparing an operating condition of the storage means (20) with a preset operating condition and a display means (40) for displaying a gain obtained from the calculating means (30) . The input means 10 can receive data from the engine speed detecting means 12, the discharge flow rate detecting means 14 of the hydraulic pump, and the discharge pressure detecting means 16.

The operating condition of the heavy equipment can be inputted from at least one of the controller 11 (see FIG. 4) and the sensor in the heavy equipment in place of the input means 10. In this case, the circuit configuration of the automatic gain tuning device becomes simple. When inputting data from the input means and the controller, at least one of sereal, parallel, and network may be used. The serial method is a one-to-one communication method, the connection line is simple and can be used at a relatively long distance (within about 5 meters), but the communication speed is usually slow (tens of BPS). The parallel method is a one-to-one communication method, and the connection line is complicated and used at a short distance (within about 1 meter) and the communication speed is relatively fast (about 10 times of the serial method). In addition, the network method is a one-to-many communication method. Although the connection line is simple and can be connected at the same time, it can be used up to about 100 meters without a repeater and has a high communication speed (about 1M BPS). In the case of the parallel method, since it can be used only in a short distance, it is rarely applied to the current equipment. Conventionally, the serial method is mainly used. However, since the number of controllers in the apparatus is increasing and becoming more complicated, Therefore, it is desirable to apply a network scheme capable of one-to-many connections.

The calculation means 30 compares the data inputted through the input means 10 with the optimum operating conditions of the equipment set in the storage means 20 in order to grasp the characteristics of the present equipment, If found, it obtains the optimum gain to compensate it. Next, the calculated gain is output to the user through the display means 40. [ Display means 40 may represent output in various forms, such as numbers, letters, or sounds.

In order to determine the operating characteristics of the pump, it is necessary to know which flow rate is discharged at which pressure, so that the discharge pressure of the pump is detected. Further, in order to grasp the operating characteristics of the engine, the current engine speed is detected, and the inclination angle of the swash plate for discharging the desired flow rate by inputting the discharge flow rate and the discharge pressure at a given engine speed can be calculated. That is, the engine rotation speed or the inclination angle of the swash plate for discharging the required flow rate according to the operation state of the equipment is calculated and outputted to the user through the display means.

In the present invention, two methods can be used to obtain the optimum gain. That is, there is a method of fixing the engine speed and changing the maximum swash angle, and conversely, a method of fixing the maximum swash angle and changing the engine speed.

In the first method, the inherent characteristics such as, for example, the highest fuel efficiency and the less noise can be obtained and maintained by the set engine speed, but the maximum discharge flow rate of the pump is reduced, and the workability is somewhat lowered .

In this method, for example, the maximum discharge flow rate Q (see FIG. 2) of a hydraulic pump such as a variable displacement pump is a function of 1, N and P. In other words,

Q = f (1, N, P)

Where Q is the discharge flow rate, 1 is the maximum swash plate angle, N is the engine speed, and P is the discharge pressure. Therefore, the maximum swash angle is

1 = g (Q, N, P)

(However, it is applicable when the engine horsepower is known accurately).

In order to obtain engine horsepower experimentally, a test apparatus is constructed as shown in FIG. Next, by adjusting the engine to the desired engine speed and gradually increasing the limit value of the swash angle of the pump while releasing the equipment to discharge the maximum flow rate, The discharge pressure and the discharge flow rate at the time point when the discharge pressure is lowered are the horsepower of the engine, so that the horsepower curve of the engine can be known. Using the engine horsepower at this time, perform mathematical calculations to obtain 1, or use the values from the experimental procedure.

In the second method, the inherent characteristics such as, for example, the highest mileage and less noise are reduced by the set engine speed, but the workability can be maintained by maintaining the work flow rate. When the engine and the variable displacement pump are provided and the maximum discharge flow rate to be used is determined, the horsepower curve of the engine must be above the PQ line of the pump as shown in FIG. 2. Therefore, Mathematically. The engine speed N is

N = h (Q, 1, P)

.

In order to experimentally determine the engine speed, it is necessary to set the limit value of the swash plate angle to select the desired maximum flow rate, and then gradually reduce the engine speed from the maximum while relieving the equipment to obtain the engine speed at which the desired maximum flow rate is discharged (However, the condition of TN ≥ PQ must be satisfied).

As described above, the automatic gain tuning apparatus and method according to the preferred embodiment of the present invention reduces development personnel and duration in the controller development stage of a heavy equipment, Since the gain can be tuned easily, it is possible to maximize the efficiency by keeping the performance of the heavy equipment at the optimum level at all times.

Claims (6)

An automatic gain tuning device for automatically tuning a gain of an engine speed control value of a heavy equipment engine or an adjustment amount of a swash plate angle of a hydraulic pump, the automatic gain tuning device comprising input means for inputting a current operating condition of the heavy equipment, A calculation means for calculating a gain by comparing an operating condition from the input means with an operating condition preset in the storing means, and a calculating means for calculating a gain, And a display means for displaying a gain obtained from the automatic gain tuning device. The automatic gain tuning device according to claim 1, wherein the input means is configured to receive an operating condition of a heavy equipment from at least one of a controller and a sensor in the heavy equipment. The automatic gain tuning device according to claim 1 or 2, wherein at least one of serial, parallel, and network is used for data input from the input means and the controller. An automatic gain tuning method for automatically tuning a gain of an engine speed control value of a heavy equipment or an adjustment amount of a swash plate angle of a hydraulic pump, the method comprising: inputting a current operating condition of the heavy equipment; Calculating a gain in comparison with a preset operating condition at the time of operation, and displaying the calculated gain. 5. The automatic gain tuning method according to claim 4, wherein the gain is calculated so as to fix the rotational speed of the engine and change the maximum swash plate angle of the hydraulic pump in the calculating step. The automatic gain tuning method according to claim 4, wherein the gain is calculated so as to fix the maximum swash plate angle of the hydraulic pump and change the engine speed in the calculating step.