CN104033260A - Engine speed control method, device and system and engineering machinery - Google Patents

Abstract

The invention discloses an engine rotating speed control method, engine rotating speed control equipment, an engine rotating speed control system and engineering machinery, wherein the method comprises the following steps: receiving a current cycle displacement output value q of a variable displacement pump of a construction machine_m1And a target displacement output value q_p(ii) a Outputting a value q according to the current cycle displacement_m1And the target displacement output value q_pCalculating displacement control quantity q of variable pump_t(ii) a And controlling the quantity q according to the displacement of the variable pump_tMaximum current I of displacement control valve of variable displacement pump_maxOpening current I of displacement control valve of variable displacement pump_minMaximum displacement q of variable displacement pump_maxObtaining the control current I of the displacement control valve of the variable displacement pump_tTo control the engine speed by adjusting the displacement of the variable displacement pump. The invention can control the rotating speed of the engine in time to keep the rotating speed stable, thereby integrally inhibiting the sudden change of the load, effectively reducing the dropping rate of the engine, and simultaneously reducing the possible additional problems of overshoot, oscillation and the like of the anti-dropping speed model in the prior art.

Description

Control method for engine speed, equipment, system and engineering machinery

Technical field

The present invention relates to engineering machinery field, particularly, relate to a kind of control method for engine speed, a kind of apparatus for controlling speed of engine, a kind of engine revolution speed control system and a kind of engineering machinery.

Background technique

Construction there will be because load changing (increase or reduce) causes the motor of this project machinery not react in time and makes engine speed rise suddenly, decline by engineering machinery (taking rotary drilling rig as example) in operation process, thereby have a strong impact on job stabilization, working efficiency and engine performance faults such as (for example) causing that motor is smoldered, stopped working.

For the problems referred to above, in prior art, generally fall speed value (rotating speed of target and current rotating speed poor) employing PID (Proportional according to engine speed, Integral and Derivative, proportion integration differentiation) controlling method adjusts the variable displacement pump displacement control electric current of controller output, reduce the variable displacement pump discharge capacity of rotary drilling rig, so that engine stop falls speed, until engine speed equals target setting rotating speed.

But this control method for engine speed, because causing engine speed to change, load changing has temporal delay, therefore this controlling method exist hysteresis quality in time control engine fall speed, and can cause engine speed continually among a small circle vibration.

Summary of the invention

For the above-mentioned problems in the prior art, the invention provides a kind of control method for engine speed, the method comprises: the current period discharge capacity output value q that receives the variable displacement pump of engineering machinery _m1and target discharge capacity output value q _p; According to described current period discharge capacity output value q _m1and described target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t; And according to described variable displacement pump displacement control amount q _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _t, to carry out control engine rotating speed by Moderator Variable pump delivery.

Correspondingly, the present invention also provides a kind of apparatus for controlling speed of engine, and this equipment comprises: receiver, and for receiving the current period discharge capacity output value q of variable displacement pump of engineering machinery _m1and target discharge capacity output value q _p; Controller, for according to described current period discharge capacity output value q _m1and described target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t; And also for according to described variable displacement pump displacement control amount q _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _t, and by described variable displacement pump displacement control valve control electric current I _texport to variable displacement pump displacement control valve, to carry out control engine rotating speed by Moderator Variable pump delivery.

In addition, the present invention also provides a kind of engine revolution speed control system, and this system comprises: engine rotation speed sensor, for measuring engine speed; Variable displacement pump pressure transducer, for measuring the force value of variable displacement pump of engineering machinery; According to the apparatus for controlling speed of engine of mode of execution provided by the present invention, wherein said engine rotation speed sensor is connected with described apparatus for controlling speed of engine respectively with described variable displacement pump pressure transducer, the force value of the engine speed of measurement and variable displacement pump is sent to the receiver of described apparatus for controlling speed of engine; And variable displacement pump displacement control valve, be connected with the controller of described apparatus for controlling speed of engine, for according to described variable displacement pump displacement control valve control electric current I _tregulate the discharge capacity of self, thus control engine rotating speed.

And the present invention also provides a kind of engine revolution speed control system, this system comprises: engine rotation speed sensor, for measuring engine speed; Variable displacement pump pressure transducer, for measuring the force value of variable displacement pump of engineering machinery; Metering pump pressure transducer, for measuring the force value of metering pump of described engineering machinery; And according to the apparatus for controlling speed of engine of mode of execution provided by the present invention, wherein said engine rotation speed sensor, described variable displacement pump pressure transducer and described metering pump pressure transducer are connected with described apparatus for controlling speed of engine respectively, the force value of the force value of the engine speed of measurement, variable displacement pump, metering pump is sent to the receiver of described apparatus for controlling speed of engine; And variable displacement pump displacement control valve, be connected with the controller of described apparatus for controlling speed of engine, for according to described variable displacement pump displacement control valve control electric current I _tregulate the discharge capacity of self, thus control engine rotating speed.

In addition, the present invention also provides a kind of engineering machinery, and this project machinery comprises the engine revolution speed control system according to mode of execution provided by the present invention.

Adopt control method for engine speed of the present invention, equipment and system, according to the current period discharge capacity output value q of the variable displacement pump of engineering machinery _m1and target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t, thus can be according to variable displacement pump displacement control amount q _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _tthereby carry out control engine rotating speed by Moderator Variable pump delivery, owing to pressure feedback and engine speed feedback being combined effectively controlled variable pump displacement, guaranteed that a upper cycle of variable displacement pump and the total load of current period remained unchanged, control engine rotating speed in time, makes it to keep stable, has both suppressed on the whole load changing, effectively reduce motor and fallen speed, also reduced the accessory problem such as overshoot, vibration that in prior art, anti-lost fast model may occur simultaneously.

Other features and advantages of the present invention are described in detail the embodiment part subsequently.

Brief description of the drawings

Accompanying drawing is to be used to provide a further understanding of the present invention, and forms a part for specification, is used from explanation the present invention, but is not construed as limiting the invention with embodiment one below.In the accompanying drawings:

Fig. 1 is according to the structural representation of the exemplary engine apparatus for controlling speed of one embodiment of the present invention;

Fig. 2 is according to the flow chart of the exemplary engine method for controlling number of revolution of one embodiment of the present invention; And

Fig. 3 is according to the structural representation of the exemplary engine revolution speed control system of one embodiment of the present invention.

Description of reference numerals

10 apparatus for controlling speed of engine 20 variable displacement pumps

30 metering pump 40 motors

50 engine rotation speed sensor 60 variable displacement pump pressure transducers

70 metering pump pressure transducer 80 variable displacement pump displacement control valves

100 receiver 200 controllers

Embodiment

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is elaborated.Should be understood that, embodiment described herein only, for description and interpretation the present invention, is not limited to the present invention.

Fig. 1 is according to the structural representation of the exemplary engine apparatus for controlling speed 10 of one embodiment of the present invention, and as shown in Figure 1, this equipment comprises: receiver 100, and for receiving the current period discharge capacity output value q of variable displacement pump of engineering machinery _m1and target discharge capacity output value q _p; Controller 200, for according to described current period discharge capacity output value q _m1and described target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t; And also for according to described variable displacement pump displacement control amount q _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _t, and by described variable displacement pump displacement control valve control electric current I _texport to variable displacement pump displacement control valve, to carry out control engine rotating speed by Moderator Variable pump delivery.

Specifically, receiver 100 can receive the current period discharge capacity output value q of the variable displacement pump of engineering machinery _m1and target discharge capacity output value q _p(feedback signal of for example SC system controller can be also the feedback signal of controller 200).Afterwards, receiver 100 is sent to connected controller 200, and controller 200 can be according to described current period discharge capacity output value q _m1and described target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t, that is:

Q _t=q _m1+ q _pequation (1)

According to one embodiment of the present invention, described target discharge capacity output value q _pcan fall speed value (e according to motor _n) feedback control algorithm obtain, for example obtain according to pid control algorithm:

$q_p=k_p\·e_n+k_i\·{\∫e}_n+k_d\·d\frac{e_n}{t}$ Equation (2)

Wherein said motor falls speed value e _nfor engine target rotation speed n _tengine speed n with current period ₁poor, engine target rotation speed n _tengine speed n with current period ₁measured k by engine rotation speed sensor 50 _p, k _i, k _dbe respectively ratio, integration, differential coefficient, can determine according to working control situation, should be understood that the common practise that above-mentioned pid control algorithm is related domain, in order not obscure protection scope of the present invention, does not repeat them here.And the feedback control algorithm that those skilled in the art can such as, select suitable motor to fall speed value according to actual conditions (systematic parameter requirement or fund cost etc.) obtains target discharge capacity output value q _p, for example it can be any one in pid control algorithm, fuzzy algorithmic approach and artificial neural network algorithm, the present invention does not limit this.

And, described current period discharge capacity output value q _m1can be according to the force value p in a upper cycle of described variable displacement pump _fm0, a upper cycle displacement control electric current I _m0, a upper cycle engine speed n ₀, and the force value p of the current period of described variable displacement pump _fm1, current period engine speed n ₁obtain, obtain according to following formula:

$q_{m1}=\frac{p_{m1}}{p_{\mathrm{fm}1}\·n_1}$ Equation (3)

Wherein P _m1for metering pump current period prediction output power; P _m0for the output power in a cycle on metering pump, and:

P _m0=p _fm0q _m0n ₀equation (4)

Q _m0for the discharge capacity in upper cycle of variable displacement pump, and:

Q _m0=k*I _m0equation (5)

Wherein k is setting value (configuration parameter after control valve dispatches from the factory).

The force value p in a upper cycle of variable displacement pump _fm0and the force value p of current period _fm1by variable displacement pump pressure transducer 60 measure and transmit to receiver 100, the displacement control electric current I in a upper cycle _m0by controller 200 provide, the engine speed n in a upper cycle ₀, and the engine speed n of current period ₁pass speed probe 50 measure and transmit to receiver 100 by motor.

According to one embodiment of the present invention, for the engineering machinery (for example, taking rotary drilling rig as example) of single pump, controller 200 can be set:

P _m1=P _m0equation (6)

Thereby can obtain current period discharge capacity output value q according to equation (3) _m1, and then obtain variable displacement pump displacement control amount q according to equation (1)-(2) _t.Controller 200 can be according to described variable displacement pump displacement control amount q afterwards _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _t, that is:

$I_t=q_t\·\frac{(I_{\max }-I_{\min })}{q_{\max }}+I_{\min }$ Equation (7)

Wherein, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxbe predetermined value, it is can be by controller 200 pre-stored or receive (for example manually inputting by control panel) from other equipment.Afterwards, controller 200 is by described variable displacement pump displacement control valve control electric current I _texport to variable displacement pump displacement control valve 80, for example, carry out control engine rotating speed with the discharge capacity by Moderator Variable pump 20 (making discharge capacity open large or turn down).

Adopt above-mentioned mode of execution of the present invention that pressure feedback (Power Balance Model) and engine speed feedback (anti-lost fast model) is combined the aperture of controlled variable pump displacement control valve 80 effectively, because pressure feedback is faster than engine speed feedback, and above-mentioned mode of execution had guaranteed that a upper cycle of variable displacement pump and the total load of current period remained unchanged, make this equipment control engine rotating speed in time, make it to keep stable, suppressed on the whole load changing, effectively reduce motor and fallen speed, also reduced the overshoot that in prior art, anti-lost fast model may occur simultaneously, the accessory problems such as vibration.

According to another embodiment of the invention, for the engineering machinery of double pump, for example, taking rotary drilling rig as example, Fig. 3 is according to the structural representation of the exemplary engine revolution speed control system of one embodiment of the present invention, as shown in Figure 3, wherein can comprise metering pump 30 and variable displacement pump 20.For this situation, in order to obtain more accurately current period discharge capacity output value q _m1, controller 200 can be set:

P _m1=P _m0+ P _a0-P _a1equation (8)

Wherein P _a0and P _a1for a upper cycle of metering pump 30 and the bearing power of current period, and, P _a0=p _fa0q _a0n ₀, q _a0=k*I _a0equation (9); P _a1=p _fa1q _a1n ₁, q _a1=k*I _a1equation (10), wherein k is setting value (configuration parameter after control valve dispatches from the factory), the force value p in a upper cycle of variable displacement pump _fm0and the force value p of current period _fm1by variable displacement pump pressure transducer 60 measure and transmit to receiver 100, the force value p in a upper cycle of metering pump _fa0and the force value p of current period _fa1by metering pump pressure transducer 70 measure and transmit to receiver 100, the displacement control electric current I in a upper cycle of variable displacement pump _m0, metering pump the displacement control electric current I in a upper cycle _a0and the displacement control electric current I of current period _a1provided the engine speed n in a upper cycle of variable displacement pump and metering pump by controller 200 ₀and the engine speed n of current period ₁pass speed probe 50 measure and transmit to receiver 100 by motor.

Therefore, under this mode of execution, current period discharge capacity output value q _m1can be according to the force value p in a upper cycle of described variable displacement pump _fm0, a upper cycle displacement control electric current I _m0, a upper cycle engine speed n ₀, current period force value p _fm1, current period engine speed n ₁, and the force value p in upper cycle of the metering pump of described engineering machinery _fa0, a upper cycle displacement control electric current I _a0, a upper cycle engine speed n ₀, current period force value p _fa1, current period displacement control electric current I _a1, current period engine speed n ₁obtain wherein I _a0=I _a1.Afterwards, controller 200 can be described above, calculates variable displacement pump displacement control valve control electric current I according to above-mentioned equation _tand export to variable displacement pump displacement control valve 80, for example, carry out control engine rotating speed with the discharge capacity by Moderator Variable pump 20 (making discharge capacity open large or turn down).Adopt this mode of execution, owing to guaranteeing that a upper cycle of variable displacement pump and the total load of current period remained unchanged, control engine rotating speed in time thus, make it to keep stable, suppressed on the whole load changing, effectively reduce motor and fallen speed, also reduced the accessory problem such as overshoot, vibration that in prior art, anti-lost fast model may occur simultaneously.

Accordingly, Fig. 2 is that as shown in Figure 2, the method comprises according to the flow chart of the exemplary engine method for controlling number of revolution of one embodiment of the present invention:

In step 1001, receive the current period discharge capacity output value q of the variable displacement pump of engineering machinery _m1and target discharge capacity output value q _p;

In step 1002, according to described current period discharge capacity output value q _m1and described target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t; And

In step 1003, according to described variable displacement pump displacement control amount q _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _t, to carry out control engine rotating speed by Moderator Variable pump delivery.

Preferably, described target discharge capacity output value q _pthe feedback control algorithm that falls speed value according to motor obtains, and it is engine target rotation speed n that wherein said motor falls speed value _tengine speed n with current period ₁poor.

Preferably, described current period discharge capacity output value q _m1according to the force value p in a upper cycle of described variable displacement pump _fm0, a upper cycle displacement control electric current I _m0, a upper cycle engine speed n ₀, and the force value p of the current period of described variable displacement pump _fm1, current period engine speed n ₁obtain.

Preferably, described current period discharge capacity output value q _m1according to the force value p in a upper cycle of described variable displacement pump _fm0, a upper cycle displacement control electric current I _m0, a upper cycle engine speed n ₀, current period force value p _fm1, current period engine speed n ₁, and the force value p in upper cycle of the metering pump of described engineering machinery _fa0, a upper cycle displacement control electric current I _a0, a upper cycle engine speed n ₀, current period force value p _fa1, current period displacement control electric current I _a1, current period engine speed n ₁obtain wherein I _a0=I _a1.

Preferably, described feedback control algorithm is any one in pid control algorithm, fuzzy algorithmic approach and artificial neural network algorithm.

In said method step for current period discharge capacity output value q _m1, target discharge capacity output value q _p, variable displacement pump displacement control valve control electric current I _tand the mode of execution of the acquisition of other parameters etc. is described above, does not repeat them here.

Correspondingly, the invention provides a kind of engine revolution speed control system, this system comprises: engine rotation speed sensor 50, for measuring above-mentioned engine speed; Variable displacement pump pressure transducer 60, for measuring the force value of above-mentioned variable displacement pump of engineering machinery; According to the apparatus for controlling speed of engine 10 of a kind of mode of execution provided by the present invention, wherein said engine rotation speed sensor 50 is connected with described apparatus for controlling speed of engine 10 respectively with described variable displacement pump pressure transducer 60, the force value of the engine speed of measurement and variable displacement pump is sent to the receiver 100 of described apparatus for controlling speed of engine; And variable displacement pump displacement control valve 80, be connected with the controller 200 of described apparatus for controlling speed of engine 10, for according to described variable displacement pump displacement control valve control electric current I _tregulate the discharge capacity of self, thus control engine rotating speed.

In addition, according to another embodiment of the invention, as shown in Figure 3, for the engineering machinery that comprises variable displacement pump 20 and metering pump 30, the present invention also provides a kind of engine revolution speed control system, and this system comprises: engine rotation speed sensor 50, for measuring above-mentioned engine speed; Variable displacement pump pressure transducer 60, for measuring the force value of above-mentioned variable displacement pump of engineering machinery; Metering pump pressure transducer 70, for measuring the force value of above-mentioned metering pump of described engineering machinery; And according to the apparatus for controlling speed of engine 10 of another kind of mode of execution provided by the present invention, wherein said engine rotation speed sensor 50, described variable displacement pump pressure transducer 60 and described metering pump pressure transducer 70 are connected with described apparatus for controlling speed of engine 10 respectively, the force value of the force value of the engine speed of measurement, variable displacement pump, metering pump is sent to the receiver 100 of described apparatus for controlling speed of engine 10; And variable displacement pump displacement control valve 80, be connected with the controller 200 of described apparatus for controlling speed of engine 10, for according to described variable displacement pump displacement control valve control electric current I _tregulate the discharge capacity of self, thus control engine rotating speed.

Correspondingly, it is a kind of according to the engineering machinery (not shown) of the engine revolution speed control system of embodiment of the present invention that the present invention also provides, this project machinery not only can comprise the engine revolution speed control system according to embodiment of the present invention as mentioned above, and this project machinery also can adopt above-mentioned control method for engine speed to carry out above-mentioned control operation.Should be understood that, this project machinery can be any equipment that need to become variable displacement pump and/or metering pump, for example rotary drilling rig.

Adopt control method for engine speed of the present invention, equipment and system, according to the current period discharge capacity output value q of the variable displacement pump of engineering machinery _m1and target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t, thus can be according to variable displacement pump displacement control amount q _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _tthereby carry out control engine rotating speed by Moderator Variable pump delivery, owing to pressure feedback and engine speed feedback being combined effectively controlled variable pump displacement, guaranteed that a upper cycle of variable displacement pump and the total load of current period remained unchanged, control engine rotating speed in time, makes it to keep stable, has both suppressed on the whole load changing, effectively reduce motor and fallen speed, also reduced the accessory problem such as overshoot, vibration that in prior art, anti-lost fast model may occur simultaneously.

Below describe by reference to the accompanying drawings the preferred embodiment of the present invention in detail; but; the present invention is not limited to the detail in above-mentioned mode of execution; within the scope of technical conceive of the present invention; can carry out multiple simple variant to technological scheme of the present invention, these simple variant all belong to protection scope of the present invention.

It should be noted that in addition, each concrete technical characteristics described in above-mentioned embodiment, in reconcilable situation, can combine by any suitable mode, for fear of unnecessary repetition, the present invention is to the explanation no longer separately of various possible compound modes.

In addition, also can carry out combination in any between various mode of execution of the present invention, as long as it is without prejudice to thought of the present invention, it should be considered as content disclosed in this invention equally.

Claims (13)

1. a control method for engine speed, is characterized in that, the method comprises:

Receive the current period discharge capacity output value q of the variable displacement pump of engineering machinery _m1and target discharge capacity output value q _p;

According to described current period discharge capacity output value q _m1and described target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t; And

According to described variable displacement pump displacement control amount q _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _t, to carry out control engine rotating speed by Moderator Variable pump delivery.

2. control method for engine speed according to claim 1, is characterized in that, described target discharge capacity output value q _pthe feedback control algorithm that falls speed value according to motor obtains, and it is engine target rotation speed n that wherein said motor falls speed value _tengine speed n with current period ₁poor.

3. control method for engine speed according to claim 2, is characterized in that, described current period discharge capacity output value q _m1according to the force value p in a upper cycle of described variable displacement pump _fm0, a upper cycle displacement control electric current I _m0, a upper cycle engine speed n ₀, and the force value p of the current period of described variable displacement pump _fm1, current period engine speed n ₁obtain.

4. control method for engine speed according to claim 2, is characterized in that, described current period discharge capacity output value q _m1according to the force value p in a upper cycle of described variable displacement pump _fm0, a upper cycle displacement control electric current I _m0, a upper cycle engine speed n ₀, current period force value p _fm1, current period engine speed n ₁, and the force value p in upper cycle of the metering pump of described engineering machinery _fa0, a upper cycle displacement control electric current I _a0, a upper cycle engine speed n ₀, current period force value p _fa1, current period displacement control electric current I _a1, current period engine speed n ₁obtain wherein I _a0=I _a1.

5. control method for engine speed according to claim 2, is characterized in that, described feedback control algorithm is any one in pid control algorithm, fuzzy algorithmic approach and artificial neural network algorithm.

6. an apparatus for controlling speed of engine, is characterized in that, this equipment comprises:

Receiver, for receiving the current period discharge capacity output value q of variable displacement pump of engineering machinery _m1and target discharge capacity output value q _p;

Controller, for according to described current period discharge capacity output value q _m1and described target discharge capacity output value q _pcalculate variable displacement pump displacement control amount q _t; And also for according to described variable displacement pump displacement control amount q _t, variable displacement pump displacement control valve maximum current I _max, variable displacement pump displacement control valve firing current I _min, variable displacement pump maximum pump discharge q _maxobtain variable displacement pump displacement control valve control electric current I _t, and by described variable displacement pump displacement control valve control electric current I _texport to variable displacement pump displacement control valve, to carry out control engine rotating speed by Moderator Variable pump delivery.

7. apparatus for controlling speed of engine according to claim 6, is characterized in that, described target discharge capacity output value q _pthe feedback control algorithm that falls speed value according to motor obtains, and it is engine target rotation speed n that wherein said motor falls speed value _tengine speed n with current period ₁poor.

8. apparatus for controlling speed of engine according to claim 7, is characterized in that, described current period discharge capacity output value q _m1according to the force value p in a upper cycle of described variable displacement pump _fm0, a upper cycle displacement control electric current I _m0, a upper cycle engine speed n ₀, and the force value p of the current period of described variable displacement pump _fm1, current period engine speed n ₁obtain.

9. apparatus for controlling speed of engine according to claim 7, is characterized in that, described current period discharge capacity output value q _m1according to the force value p in a upper cycle of described variable displacement pump _fm0, a upper cycle displacement control electric current I _m0, a upper cycle engine speed n ₀, current period force value p _fm1, current period engine speed n ₁, and the force value p in upper cycle of the metering pump of described engineering machinery _fa0, a upper cycle displacement control electric current I _a0, a upper cycle engine speed n ₀, current period force value p _fa1, current period displacement control electric current I _a1, current period engine speed n ₁obtain wherein I _a0=I _a1.

10. equipment according to claim 7, is characterized in that, described feedback control algorithm is any one in pid control algorithm, fuzzy algorithmic approach and artificial neural network algorithm.

11. 1 kinds of engine revolution speed control systems, is characterized in that, this system comprises:

Engine rotation speed sensor, for measuring engine speed;

Variable displacement pump pressure transducer, for measuring the force value of variable displacement pump of engineering machinery;

Apparatus for controlling speed of engine according to claim 8, wherein said engine rotation speed sensor is connected with described apparatus for controlling speed of engine respectively with described variable displacement pump pressure transducer, the force value of the engine speed of measurement and variable displacement pump is sent to the receiver of described apparatus for controlling speed of engine; And

Variable displacement pump displacement control valve, is connected with the controller of described apparatus for controlling speed of engine, for according to described variable displacement pump displacement control valve control electric current I _tregulate the discharge capacity of self, thus control engine rotating speed.

12. 1 kinds of engine revolution speed control systems, is characterized in that, this system comprises:

Engine rotation speed sensor, for measuring engine speed;

Variable displacement pump pressure transducer, for measuring the force value of variable displacement pump of engineering machinery;

Metering pump pressure transducer, for measuring the force value of metering pump of described engineering machinery; And

Apparatus for controlling speed of engine according to claim 9, wherein said engine rotation speed sensor, described variable displacement pump pressure transducer and described metering pump pressure transducer are connected with described apparatus for controlling speed of engine respectively, the force value of the force value of the engine speed of measurement, variable displacement pump, metering pump is sent to the receiver of described apparatus for controlling speed of engine; And

Variable displacement pump displacement control valve, is connected with the controller of described apparatus for controlling speed of engine, for according to described variable displacement pump displacement control valve control electric current I _tregulate the discharge capacity of self, thus control engine rotating speed.

13. 1 kinds of engineering machinery, is characterized in that, this project machinery comprises according to the engine revolution speed control system described in claim 11 or 12.