JPH1162685A - Electronic control governor of diesel engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic control governor of a diesel engine which eliminates such an inconvenience according to the conventional arrangement that a dislocation appears between the actual engine speed and set engine speed owing to a dispersion among individual engines in case an engine speed control is conducted only based upon the rack position data for each engine speed value previously stored in memory and the rack position data to be calculated from the operating conditions. SOLUTION: This electronic control governor of a diesel engine acquires the position data for each engine speed of a rack previously stored in memory and the position data for the rack to be calculated from the operating conditions, calculates the one-point correction amount by the actual measurements at the stage when the rotation becomes steady for the target engine speed at the starting time, corrects the calculational rack position data for each engine speed value, and uses the obtained value as the reference for the control of the engine speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for accurately controlling the rotational speed of a diesel engine having an electronically controlled speed control device in accordance with operating conditions.

[0002]

2. Description of the Related Art Conventionally, a technology provided with an electronically controlled speed governor (electronic governor) in a diesel engine has been known. For example, JP-A-60-2
This is like the technique described in Japanese Patent No. 56529. Conventionally, the rotational speed control of a diesel engine having an electronically controlled speed governor is performed by previously collecting data on the relationship between the rack position and the rotational speed when there is no load at low and normal temperatures of cooling water for each type of engine. And stored in the memory as map data. Then, based on the cooling water temperature of the engine, the current no-load rack position is calculated from the stored data based on the no-load rack position with the engine alone or the work equipment mounted thereon, and the rotational speed control such as isochronous control or droop control is performed. A reference value or a reference value for calculating an engine load from a rack position.

[0003]

However, even in the same model, there is a variation in the no-load actual rack position for each engine, and when an estimated value is designed for the engine alone, when the engine is mounted on the working machine, , The moment of inertia due to the load of the work equipment is added, so that a deviation occurs between the actually measured value and the estimated value. Conversely, when designing with the work implement mounted, the original engine load cannot be calculated correctly. In addition, when a deviation occurs between the estimated value and the measured value of the no-load rack position, the following effects occur in governor control. For example, when performing droop control (same as a mechanical governor, the number of revolutions decreases as the load increases), the target rack position at the load at that time is calculated from the droop rate based on the estimated no-load rack position value. When the estimated value and the measured value are shifted at the no-load rack position, the target rotation speed and the actual rotation speed are shifted. In addition, at the time of starting, an excessive overshoot or an undershoot may occur when the engine speed rises and the rack control at the time of starting shifts to the normal operation rack control.

[0004]

The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described. That is, in a diesel engine, a rack actuator for adjusting the fuel injection amount of the engine, a unit for detecting the position of the rack, a unit for detecting the engine speed, a unit for setting a target speed, and an operation of the engine. Means for detecting conditions, means for storing position data of the rack for each engine speed under no load under two operating conditions, and each engine under no load under the two operating conditions In an electronically controlled speed governing device for a diesel engine having means for calculating the position of the rack with respect to each engine speed in a no-load state under the operating conditions at that time from the position data of the rack with respect to the rotational speed, after starting the engine, Under the operating conditions at that time, the speed is set to the target speed at startup with no load Then, a correction amount is calculated from the detected position of the rack and the calculated position of the rack with respect to the target rotation speed at the start in a no-load state under the operating conditions at that time, which is calculated by the calculating means. By controlling the rack position data with respect to each engine speed in a no-load state under the current operating condition calculated by the arithmetic means using the correction amount, the control is performed so that the target speed is achieved. Things.

In a diesel engine, a rack actuator for adjusting the fuel injection amount of the engine, a means for detecting the position of the rack, a means for detecting an engine speed, a means for setting a target speed, Means for detecting the operating conditions of the engine, means for storing the position data of the rack for each engine speed in an unloaded state under two operating conditions, and an unloaded state in the two operating conditions. An electronically controlled speed controller for a diesel engine having means for calculating the position of the rack with respect to each engine speed under no-load conditions under the current operating conditions from the position data of the rack with respect to each engine speed. After starting the engine, under the current operating conditions, with no load, When the secondary time rate of change of the rotation speed is settled, the target rotation speed at the time of starting in a no-load state under the operating conditions at that time is calculated by the detected value of the position of the rack and the calculation means. The correction amount is calculated from the calculated position of the rack with respect to the position, and the position data of the rack for each engine speed in the no-load state under the current operating condition calculated by the calculation means is corrected by the correction amount. By doing so, control is performed so as to reach the target rotation speed.

Further, by adding a nonvolatile memory for storing the correction amount and a storage timing signal generating means, the correction amount is stored at the start of the adjustment operation, and the correction amount is stored at the subsequent operation. , It was corrected.

[0007]

Next, an embodiment of the present invention will be described. FIG. 1 is a control block diagram of a diesel engine equipped with the electronic control type governing device of the present invention, FIG. 2 is a diagram showing a relationship between an engine speed and a rack position, and FIG. 3 is a diagram of the engine during no-load operation of the engine. FIG. 4 is a diagram showing the relationship between the number of revolutions and the rack position, FIG. 4 is a diagram showing the change over time in the number of revolutions of the engine and the rack position, and FIG.
FIG. 6 is a diagram showing the engine speed, the primary time change rate of the engine speed, the secondary time change rate of the engine speed, and the time change of the rack position, and FIG. FIG. 8 is a flowchart of control when the next time change rate is set as a correction condition, and FIG. 8 is a flowchart in which a nonvolatile memory for storing a storage timing signal and a correction amount is added.

The configuration of an engine equipped with the electronically controlled speed governor of the present invention will be described with reference to FIG. A fuel injection pump P is attached to the engine E, and a governor G is attached to the fuel injection pump P. The governor section G is provided with a rack actuator 5 for driving the rack 2 for adjusting the fuel injection amount, a rack position sensor 11, and a rotation speed sensor 12 of the engine E. The fuel injection amount adjusting rack changes the effective stroke of the plunger of the fuel injection pump P. The rack actuator 5 is constituted by a linear solenoid, and slides on a fuel injection amount adjusting rack by the operation of the rack actuator 5.
Of the rack actuator 5 is controlled by a drive signal from the controller C.

The position of the operating portion of the rack actuator 5 is detected by a rack position sensor 11, and the rack position sensor 11 is connected to an input interface 16 of the controller C. Further, a cooling water temperature sensor 19 is provided on a radiator of the engine E. In addition, an accelerator lever is disposed on the operation unit as a setting device for setting the target rotation speed 22, and an accelerator lever position sensor is disposed on a rotation base of the accelerator lever. Further, a key switch for starting the engine E is arranged on the operation unit.

The controller C comprises a CPU 13, a memory 14, an output interface 15, and an input interface 16. The output interface 15 is connected to the rack actuator 5, and the input interface 16 is connected to the rack position sensor 11, the rotation speed sensor 12, A cooling water temperature sensor 19, a target rotation speed 22, a storage timing signal 23, and a start start signal 24 are input. The no-load rack position ((a), (b) in FIG. 2) and the starting rack position ((h) in FIG. 2) corresponding to each engine speed at low and normal cooling water temperatures are stored in the memory 14. Are stored as map data.

An example of the rack characteristic map in such a configuration will be described. The relationship between the rack position and the engine speed is as shown in FIG. 2. When the cooling water is at a low temperature and there is no load, the relationship is (a), and when the cooling water is at normal temperature and there is no load, (b). When the calculation is performed according to the cooling water temperature with no load, the relationship becomes (c). (D) When the position is set to the target rotational speed reference value with no load, (e) is the relationship when the isochronous control is performed, and the engine rotational speed is kept constant even if the load changes. Control. (F) shows a case where droop control is performed, in which the engine speed decreases as the load increases, and the engine speed increases as the load decreases. Note that (g) shows the maximum rack position, and (h) shows the starting rack position.

FIG. 3 shows a map during no-load operation.
(I) is (c) in FIG. That is, it is a map calculated from FIGS. 2A and 2B.
(J) is a map of the set rotation speed and the actually measured value of the rack position. Here, the engine cannot be manufactured in exactly the same manner, and changes due to the mounting of a working machine or the like, so that a shift (K) usually occurs. At this time, if the engine speed is set to N1, the controller C drives the rack actuator 5 to set the rack to L1. However, the converged position (actually measured value) is (m), and the rotation speed is N2, which is shifted by (N2-N1).
It is necessary to By setting the deviation (k) of (L2−L1) as a correction value and adding the deviation (k) to the no-load set value (reference value) (n), the set value and the actually measured value are made coincident. By making the map of (i) the map of (j), it is possible to perform accurate rotation speed control according to the engine.

Next, control for correcting the deviation (k) of the present invention will be described with reference to FIGS. First, when the key switch is turned on (t1), the engine speed N, the target engine speed 22, the actual measured value from the rack position sensor 11, and the water temperature from the cooling water temperature sensor 19 are detected from the engine speed sensor 12. Is stored in the memory 14 (S1). Then, the cell motor is driven (t2) to determine whether the start of the engine E is completed (S2). This start determination is made on the assumption that the start is completed when the engine E becomes equal to or higher than the specified number of revolutions (when t3 has elapsed). If the starting has not been completed, the starting rack position is read from the map data from the map data (S3), and output to the rack actuator 5 so as to become the target rack position (S12). At this time, as shown in FIG. 4, the rack position is a set position for starting, and the rotation speed is a fixed rotation speed since the rotation is driven by the cell motor. To increase.

When the start of the engine E is completed (S2),
From the target rotation speed 22, the cooling water temperature, and the map data, a no-load rack position (reference target rotation speed) corresponding to the target rotation speed is calculated (S4), and it is determined whether the correction amount has been calculated (S5). If the correction amount has not been calculated, the engine E
Is not settled (this stabilization of the engine speed is defined as the engine speed settled) (S6) First, the no-load rack position is set as a reference for rack control (S7). The target rack position for normal operation is calculated from the target rotation speed and the engine rotation speed in accordance with the control mode (droop control or isochronous control) (S11), and the process proceeds to step S12.

If the engine speed is settled in step S6, the correction amount is calculated from the unloaded rack position at the target speed at the cooling water temperature calculated from the map data and the detected rack position (actually measured value). Is calculated (S8). The correction amount is read into the memory 14 (S
9). Next, the no-load rack position at each engine speed at the cooling water temperature calculated from the map data is corrected by the correction amount and used as a rack control reference value (S1).
0). Then, a target rack position for normal operation (a rack control reference value) is calculated from the target rotation speed and the engine rotation speed in accordance with the control mode (droop control or isochronous control) (S11), and the process proceeds to step S12.

As shown in FIGS. 6 and 7, when the key switch is turned on, the engine speed N from the engine speed sensor 12, the target engine speed 22, and the rack position sensor 11 are turned on.
And the water temperature is detected from the cooling water temperature sensor 19, and the respective values are read into the memory 14 (S10
1). Then, the cell motor is driven to start the engine E, and it is determined whether the start of the engine E is completed (S10).
2) If the start of the engine E is not completed, the data of the target rack position at the start is read from the map data (S103), and the correction amount (initial value) is set to 0 (S1).
04). Then, an output is made to the rack actuator 5 so as to reach the target rack position (S114).

When the start of the engine E is completed (S10)
2), the no-load rack position (based on the target number of revolutions) is calculated from the target rotation speed 22, the water temperature from the cooling water temperature sensor 19, and the map data (S105), and it is determined whether or not the no-load rack correction calculation mode has been completed. A determination is made (S106), and if it has been completed, the flow proceeds to step S113 described later. If not completed, the primary time rate of change dN / dt is calculated from the previous (when the start is completed at the first time) and the current engine speed (S107), and dN / dt is settled (converged). It is determined that the engine speed has settled, and the no-load rack correction mode is completed (S108).
Proceed to 113.

If the dN / dt is not settled, the secondary time change rate d ² N / dt ² is further calculated (S109), and the secondary time change rate converges (settles). If not, the process proceeds to step S113 to be described later. If the secondary time rate of change is settled, the unloaded rack position at the target rotation speed at the cooling water temperature calculated from the map data and the rack position actual measurement The correction amount is calculated from the value (S111). Then, the no-load rack position at each engine speed at the cooling water temperature calculated from the map data is corrected by the correction amount and used as a rack control reference value (S112), and the control mode (droop control or isochronous control) is performed. Then, the target rack position for normal operation is calculated from the target rotation speed and the engine rotation speed (S113), and is output to the rack actuator so as to reach the target rack position (S114).

As shown in FIG. 8, the correction amount is stored by adding a nonvolatile memory for storing the correction amount and a step of determining ON / OFF of the storage timing signal after the start completion determination. The correction amount can be calculated only when it is desired (or updated) (for example, during shipping operation or adjustment operation).

In this embodiment, the operating condition is the cooling water temperature, but the lubricating oil temperature may be the operating condition.

[0021]

According to the present invention having the above-described structure, the following effects can be obtained. In an electronically controlled speed control device for a diesel engine, the actual measured position of the rack when the engine is started and the rotation speed is settled with respect to the target rotation speed at startup, and two operating conditions stored in advance (this embodiment At the time of starting under the operating conditions (cooling water temperature in the present embodiment) at that time calculated by the rack position data with respect to each engine speed in a no-load state when the cooling water temperature is low and normal temperature). A correction amount is calculated from the no-load rack position with respect to the target rotation speed, and the no-load state under two predetermined operating conditions (in this embodiment, when the cooling water temperature is low and at room temperature) is calculated based on the correction amount. In,
Operating conditions at that time calculated from rack position data for each engine speed (cooling water temperature in this embodiment)
By correcting the no-load rack position data with respect to each engine speed in the above, and using it as the reference value of rack control for each engine speed in the load state, the variation for each engine is corrected and more accurately matched to each The rotation control became possible.

Further, by calculating the correction amount when the secondary time change rate of the rotation speed is settled with respect to the target rotation speed at the time of starting, the correction amount is calculated rather than calculating the correction amount when the rotation speed is settled. The correction amount can be determined quickly, and the rotation control can be performed more quickly.

Further, by adding a nonvolatile memory for storing the correction amount and a storage timing signal generating means, for example, at the time of shipping operation or adjustment operation, if the correction amount is stored, Therefore, the time for calculating the correction amount can be saved, and the rotation speed control can be performed with a correspondingly small time lag.

[Brief description of the drawings]

FIG. 1 is a control block diagram of a diesel engine equipped with an electronically controlled speed governor of the present invention.

FIG. 2 is a diagram showing a relationship between an engine speed and a rack position.

FIG. 3 is a diagram showing the relationship between the number of revolutions of the engine and the rack position when the engine is running under no load.

FIG. 4 is a diagram showing a change over time of an engine speed and a rack position.

FIG. 5 is a flowchart of the control of the present invention.

FIG. 6 shows the engine speed, the first-order time rate of change of the engine speed, the second-order time rate of change of the engine speed,
It is a figure showing a temporal change of a rack position.

FIG. 7 is a flowchart of control when a secondary time rate of change of the engine speed is set as a correction condition.

FIG. 8 is a flowchart to which a nonvolatile memory for storing a storage timing signal and a correction amount is added.

[Explanation of symbols]

 C Controller E Engine G Governor P Fuel injection pump 5 Rack actuator 11 Rack position sensor 12 Speed sensor 19 Cooling water temperature sensor

Claims (6)

[Claims] 1. A diesel engine, a rack actuator for adjusting an engine fuel injection amount,
A means for detecting the position of the rack, a means for detecting an engine speed, a means for setting a target speed, and a means for detecting an operating condition of the engine. Means for storing the position data of the rack for each engine speed, and in the no-load state under the two operating conditions, the position data of the rack for each engine speed in the no-load state under the operating conditions at that time. In an electronically controlled speed governor for a diesel engine having means for calculating the position of the rack with respect to each engine speed, after starting the engine, under operating conditions at that time, in a no-load state, with respect to a target speed at the start, When the rotation speed is settled, the detected value of the position of the rack is calculated by the calculation means and the detection value of the rack at the operating condition at that time. Under load conditions, a correction amount is calculated from the calculated position of the rack with respect to the target rotation speed at the time of starting, and under the no-load condition under the current operating conditions calculated by the calculation means using the correction amount. An electronically controlled speed controller for a diesel engine, wherein position data of the rack for each engine speed is corrected. 2. The method according to claim 1, wherein “there are two conditions”.
An electronically controlled diesel engine governor with "Cooling water temperature low and normal temperature" and "Operating conditions""Cooling water temperature". 3. A non-volatile memory for storing the correction amount and a storage timing signal generating means are added to store the correction amount at the start of the adjustment operation, and to store the correction amount at the subsequent operation. 3. The electronically controlled governing device for a diesel engine according to claim 1, wherein the compensation is performed. 4. In a diesel engine, an actuator of a rack for adjusting a fuel injection amount of the engine,
A means for detecting a position of the rack, a means for detecting an engine speed, a means for setting a target speed, a means for detecting an operating condition of the engine, Means for storing the position data of the rack for each engine speed, and the no-load condition under the operating conditions at that time from the position data of the rack for each engine speed in the no-load condition under the two operating conditions. In the electronically controlled governor of a diesel engine having means for calculating the position of the rack with respect to each engine speed, after starting the engine,
Under the operating conditions at that time, when the secondary time rate of change of the rotation speed with respect to the target rotation speed at the start is settled under no load, the detected value of the position of the rack is calculated by the calculation means. The correction amount is calculated from the calculated position of the rack with respect to the target rotation speed at the start in a no-load state under the operating conditions at that time, and the operation at that time is calculated by the calculation means based on the correction amount. An electronically controlled speed control device for a diesel engine, wherein position data of the rack for each engine speed in a no-load state under conditions is corrected. 5. An electronically controlled speed control system for a diesel engine according to claim 4, wherein the “two operating conditions” are “cooling water temperature low temperature and normal temperature” and the “operating condition” is “cooling water temperature”. apparatus. 6. The correction amount is stored at the time of starting the adjustment operation by adding a nonvolatile memory for storing the correction amount and a storage timing signal generating means. 6. The electronically controlled speed control device for a diesel engine according to claim 4, wherein the correction is performed.