CN104020721A - Numerically-controlled machine tool spindle rotation acceleration power and energy consumption obtaining and energy-saving control method - Google Patents

Abstract

The invention discloses a numerically-controlled machine tool spindle rotation acceleration power and energy consumption obtaining and energy-saving control method. The method comprises the following steps: step 1) controlling a spindle to rotate and obtaining a spindle rotation power equation PSR (n), wherein the n is spindle rotation speed; step 2) obtaining design parameters, obtaining a computation formula of the spindle rotation acceleration power according to the spindle rotation power equation and the design parameters, and further obtaining a computation formula of the energy consumption; step 3) changing acceleration time of a spindle frequency converter and carrying out calculating to obtain spindle rotation acceleration power peak value and energy consumption; and step 4) selecting appropriate acceleration time of the spindle frequency converter to control the spindle so as to enable the spindle rotation acceleration power peak value is less than the preset upper limit value and the energy consumption is minimum. The power and energy consumption in the numerically-controlled machine tool spindle rotation acceleration process can be obtained only through carrying out a simple spindle rotation experiment and then with theoretical analysis and machine tool design and manufacture parameters being combined, and thus energy-saving control of the machine tool can be achieved.

Description

Obtaining and energy-saving control method of main shaft of numerical control machine tool Spin-up power energy consumption

Technical field

The present invention relates to Machine-Tool Control field, relate in particular to obtaining and energy-saving control method of a kind of main shaft of numerical control machine tool Spin-up power energy consumption.

Background technology

Main shaft Spin-up is that main shaft is by static startup or by accelerate to the motion process of higher rotation speed compared with the slow-speed of revolution.At present, numerically-controlled machine main transmission adopts the type of drive of " frequency converter+asynchronous machine+mechanical drive " conventionally, by changing the output frequency of frequency converter, realizes main shaft stepless speed regulation.Main shaft Spin-up process power is very large, the large energy of short time internal consumption.This part energy is not directly used in excision workpiece material, belongs to invalid energy dissipation.Thereby, in the urgent need to the acquisition methods of research main shaft Spin-up power and energy consumption, and then reduce this part energy dissipation.

At present, domestic main transmission system of machine tool power and energy consumption obtain aspect more existing researchs.Publication number is that the patent documentation of 102637014A discloses the method that the dynamo-electric main transmission energy efficiency of numerically-controlled machine process is obtained, adopt the method for experiment to obtain lathe no-load power function and additional load loss factor function, and then according to main transmission system of machine tool power input to machine curve in process, obtain the energy efficiency of the dynamo-electric main transmission of machine tooling process.Publication number is that the patent documentation of 102179727A discloses a kind of main transmission system of machine tool process consumption information online test method, application main transmission energy flow and main consumption information mathematical model, by the total power input of online detection lathe, just can obtain the real time datas such as spindle motor loss power, spindle motor output power, machine driven system loss power, cutting power.Publication number is that the patent documentation of 102744649A discloses the non-cutting energy consumption of a kind of numerically controlled lathe main transmission acquisition methods, adopt the method for experiment to obtain main transmission frequency converter and spindle motor no-load power, and the coefficient such as main shaft idle running friction torque, main transmission moment of inertia, spindle angular acceleration, and then obtain main shaft Spin-up power and energy consumption.The weak point of this invention is that in model, all coefficients all obtain by experiment, and experiment and data analysis are complicated, waste time and energy; And to model, do not react Machine Tool design parameter with the relation between energy consumption, cannot be for instructing lathe Energy Saving Control.

In sum, power when current patent is moved with constant rotational speed mainly for main transmission system of machine tool obtains and monitors, and while seldom having for rotation speed change, the power of main transmission is studied.Main shaft Spin-up process rotating speed constantly changes, and power consumption is very large, in the urgent need to its power and energy consumption are obtained, and then instructs energy-saving design and the control of lathe.

Summary of the invention

Main transmission during for rotation speed change, predicts main shaft Spin-up power and energy consumption, according to predicting the outcome, selects the acceleration time of main shaft of numerical control machine tool frequency converter, thereby realizes the Energy Saving Control of numerically-controlled machine.

Obtaining and an energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption, comprises the steps:

Step 1, controls main shaft with different speed of mainshaft rotations, and obtains main shaft rotary power equation P _sR(n), wherein n is the speed of mainshaft;

Step 2, obtains the design parameter of main shaft, according to main shaft rotary power equation and design parameter, obtains main shaft Spin-up power P _sRA(t) computing formula, and further obtain the computing formula of energy consumption, the computing formula of main shaft Spin-up power is:

P _SRA(t)=P _SR(n)+J _sα _Mω _M，

Wherein, t is the time, and span is at [0, t _sRA], t _sRArepresent the main shaft Spin-up duration, J _sthat axis system equivalence is to the moment of inertia of machine shaft, α _mspindle motor angular acceleration, ω _mbe spindle motor angular velocity, and spindle motor angular acceleration and spindle motor angular velocity change with the variation of the acceleration time of spindle inverters;

Step 3, set the initial speed of mainshaft and the final speed of mainshaft of main shaft Spin-up, change the acceleration time of spindle inverters, be updated to the computing formula of main shaft Spin-up power and energy consumption, calculate the different values of main shaft Spin-up power peak and energy consumption;

Step 4, according to the different values of main shaft Spin-up power peak and energy consumption, controls the main shaft of numerically-controlled machine, selects the acceleration time of suitable spindle inverters, makes main shaft Spin-up power peak be less than default power upper limit value and energy consumption reaches minimum.

Main shaft Spin-up power P _sRA(t) by two parts, formed: a part is for maintaining the power of main shaft rotation, equaling the main shaft rotary power P under present speed _sR(n); Another part is the power that main shaft is accelerated for overcoming spindle machine kinematic train inertia, equals moment of inertia J _s, spindle motor angular acceleration _mwith spindle motor angular velocity omega _mproduct.Rear portion is along with the acceleration time of spindle inverters changes and changes, and therefore, when changing the acceleration time of spindle inverters, main shaft Spin-up power changes, thereby energy consumption also changes.

In step 1, obtain main shaft rotary power equation P _sR(n) method is as follows:

Step 1-1, lathe standby power P when measurement main shaft is static _sO;

Step 1-2, sets the interval that the speed of mainshaft increases progressively, and controls the speed of mainshaft and with the interval setting, increases progressively between maximum principal axis rotating speed zero, is rotated, and obtains the main shaft rotary power of the corresponding speed of mainshaft;

Step 1-3, take speed of mainshaft n as independent variable, main shaft rotary power P _sRfor dependent variable, by the regretional analysis of segmentation once linear, obtain main shaft rotary power equation.

In step 1-2, main shaft rotary power obtain manner corresponding to each speed of mainshaft be, measures the machine power of the corresponding empty cutting spindle rotation of each speed of mainshaft, deducts lathe standby power P _sO, obtain the main shaft rotary power under this speed of mainshaft.

In step 1-3, the method that obtains main shaft rotary power equation by the regretional analysis of segmentation once linear is, take the speed of mainshaft as horizontal ordinate, and main shaft rotary power is ordinate, draw the functional arrangement of main shaft rotary power, observing and obtaining the most obvious two the some horizontal ordinates of slope variation is n _p1and n _p2, at n ∈ (0, n _p1], n ∈ (n _p1, n _p2] and n ∈ (n _p2, n _max] each interval range in, take n as independent variable, P _sRfor dependent variable, carry out once linear regretional analysis, gained main shaft rotary power equation is piecewise function, wherein n _maxit is the main shaft rotation maximum (top) speed of setting.

The rule that main shaft rotary power changes with the speed of mainshaft can be divided into three sections, and when spindle motor moves below frequency converter fundamental frequency, main shaft rotary power is monotone increasing with the increase of the speed of mainshaft; When spindle motor moves more than frequency converter fundamental frequency, main shaft rotary power first reduces or faint increase with the increase of the speed of mainshaft; Along with frequency converter frequency further increases, main shaft rotary power increases with the increase of the speed of mainshaft.Thereby main shaft rotary power is represented to become the piecewise function of the speed of mainshaft, by segmentation once linear regretional analysis matching, obtain.And by selecting the most obvious two the some horizontal ordinates of slope variation, obtained the independent variable border that piecewise linear regression is analyzed.

The computing formula of speed of mainshaft n is:

$n=n_1+\frac{60{\mathrm{uf}}_{\mathrm{BA}}t}{{\mathrm{pt}}_A},$

Wherein, n ₁for the initial speed of mainshaft, u is that main shaft is to the ratio of gear of motor output shaft, f _bAfor the basic frequency of spindle inverters, p is spindle motor magnetic pole logarithm, t _afor the acceleration time of spindle inverters.

According to this formula, can obtain, n is the function about time t, so main shaft Spin-up power is the function about time t.

Axis system equivalence is to the moment of inertia J of machine shaft _scomputing formula be:

$J_s=J_e+\underset{i=2}{\overset{m}{\mathrm{\Σ}}}{j}_i^2{J}_i,$

Wherein, J _efor the moment of inertia of spindle motor rotor, j _ifor the ratio of gear of i transmission link of main shaft to motor output shaft, J _ibe the equivalent moment of inertia of each parts of i transmission link, m is transmission link number.

The moment of inertia of spindle motor rotor, main shaft i transmission link are to the ratio of gear of motor output shaft, the equivalent moment of inertia of each parts of i transmission link and transmission link number m, these parameters are preset parameter, so axis system equivalence is to the moment of inertia J of machine shaft _sfor preset parameter.

Spindle motor angular acceleration _mcomputing formula be:

${\mathrm{\α}}_M=\frac{{2\mathrm{\πf}}_{\mathrm{BA}}}{{\mathrm{pt}}_A}.$

The basic frequency f of spindle inverters _bA, spindle motor magnetic pole logarithm p is preset parameter.

Spindle motor angular velocity omega _mcomputing formula be:

${\mathrm{\ω}}_M=\frac{2\mathrm{\π}{n}_1}{60u}+\frac{2\mathrm{\π}{f}_{\mathrm{BA}}t}{{\mathrm{pt}}_A}.$

Main shaft is preset parameter to the ratio of gear u of motor output shaft, so spindle motor angular velocity is also the function about time t.

The computing formula of energy consumption is:

$E_{\mathrm{SRA}}={\∫}_0^{t_{\mathrm{SRA}}}{P}_{\mathrm{SRA}}\left(t\right)\mathrm{dt},$

Wherein, t _sRAcomputing formula is as follows:

$t_{\mathrm{SRA}}=\frac{2\mathrm{\π}(n_2-n_1)}{60\mathrm{\α}},$

Wherein, n ₂for the final speed of mainshaft, α is spindle angular acceleration.

The computing formula of spindle angular acceleration alpha is as follows:

$\mathrm{\α}=\frac{{2\mathrm{\πuf}}_{\mathrm{BA}}}{{\mathrm{pt}}_A}.$

When main shaft Spin-up power energy consumption is obtained, the acceleration time t of spindle inverters _abe arranged on the preset parameter of lathe, initial speed of mainshaft n ₁with final speed of mainshaft n ₂it is variable element.

The present invention is directed to main shaft Spin-up energy saving optimizing, by n ₁and n ₂be made as preset parameter, change t _a, obtain different t _amain shaft rotary power and energy consumption under value condition, and then select accelerating power peak value to be less than the t that default power upper limit value and energy consumption reach hour _avalue.

Compare with background technology, the beneficial effect that the present invention has is: the present invention obtains the power data of main shaft rotation by power data harvester, and analyzes by piecewise linear regression, obtains main shaft rotary power equation P _sR(n); Then according to the rotating speed before and after the spindle parameters of numerically-controlled machine and main shaft Spin-up, calculate n and ω _mexpression formula, and parameter alpha _m, α and J _svalue, obtain main shaft Spin-up power and energy consumption; Control the acceleration time t that lathe arranges different spindle inverters _a, select peak power in power upper limit, and energy consumption corresponding t when minimum _avalue, realizes lathe Energy Saving Control.

The present invention only needs to carry out simple main shaft rotation test, and then combining with theoretical analysis and Machine Tool design Fabrication parameter, just can obtain power and the energy consumption of main shaft of numerical control machine tool Spin-up process, and then lathe is carried out to energy-saving design.

Method of the present invention is simple to operation, and the main shaft Spin-up power obtaining and energy consumption accuracy high.The present invention can be applicable to lathe energy consumption assessment, according to power and the power consumption values of the initial speed of mainshaft of input and final speed of mainshaft acquisition main shaft Spin-up; The present invention also can be applicable to lathe Energy Saving Control, controls the acceleration time that lathe is selected the most suitable spindle inverters, make peak power in power upper limit with interior and energy consumption is minimum, for the design of lathe low-carbon (LC) provides theoretical and method support.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of the inventive method;

Fig. 2 is the machine power-time curve of one embodiment of the invention gained main shaft Spin-up process;

Fig. 3 is the power-speed curves of the current embodiment gained of the present invention main shaft rotation;

Fig. 4 is the comparison diagram of main shaft Spin-up power prediction value and measured value in the current embodiment of the present invention.

Embodiment

Now by reference to the accompanying drawings and embodiment, the main shaft rotary course of numerically-controlled machine of take is example, describes main shaft Spin-up power and energy consumption acquisition methods in detail.

The CK6153i numerically-controlled machine that the selected lathe of the current embodiment of the present invention is Jinan No.1 Machine Tool Plant, its main spindle box comprises four gears, take AH gear as example, obtains main shaft Spin-up power and energy consumption, and then numerically-controlled machine is carried out to energy-saving design.

As shown in Figure 1, the step of the inventive method is as follows:

Step 1, sets maximum principal axis rotating speed, controls main shaft and rotates and obtain main shaft rotary power equation P _sR(n), wherein n is the speed of mainshaft.

Step 1-1, lathe standby power P when measurement main shaft is static _sO.

Power data harvester is connected in to lathe power input, measures standby power P _sO=328.1W.

Step 1-2, sets the interval that the speed of mainshaft increases progressively, and controls the speed of mainshaft and with the interval setting, increases progressively between maximum principal axis rotating speed zero, is rotated, and obtains the main shaft rotary power of corresponding rotating speed.

Lathe headstock handle is placed in to AH gear, controls machine tool chief axis and at 0-1500rpm, every 100rpm, be one grade and make main shaft and rotatablely move (being spaced apart 100rpm), measure machine power-time curve as shown in Figure 2.

Main shaft accelerates to specifies after rotating speed, and lathe is made main shaft and rotatablely moved, and now power is steady, choose this section of power stably data do on average, deduct standby power P _sO, obtain the rotary power of main shaft shown in table 1 table.

Table 1

Step 1-3, take speed of mainshaft n as independent variable, main shaft rotary power P _sRfor dependent variable, by the regretional analysis of segmentation once linear, obtain main shaft rotary power equation.

Take speed of mainshaft n(unit: rpm) be horizontal ordinate, main shaft rotary power P _sR(unit: W) be ordinate, (Fig. 3) observed in mapping, the speed of mainshaft (horizontal ordinate) of finding out two some correspondences of slope significant change is respectively 1000rpm and 1300rpm, respectively n ∈ (0,1000], n ∈ (1000,1300] and n ∈ (1300,1500], in interval range, take n as independent variable, P _sRfor dependent variable, do once linear regretional analysis, obtain the piecewise function of main shaft rotary power, shown in (1):

$P_{\mathrm{SR}}=\left\{\begin{array}{c}1.09n+\mathrm{41.12,0}<n\&le;1000\\ 0.558n+\mathrm{605.05,1000}<n\&le;1300\\ 1.288n-\mathrm{358.21,1300}<n\&le;1500\end{array}\right.---\left(1\right)$

P wherein _sRmain shaft rotary power for AH shelves.

Step 2, obtains the design parameter of main shaft, according to main shaft rotary power equation and design parameter, obtains main shaft Spin-up power P _sRA(t) computing formula, and further obtain the computing formula of energy consumption.

Design parameter comprises: main shaft is to the ratio of gear u of motor output shaft, the basic frequency f of spindle inverters _bA, spindle motor magnetic pole logarithm p, the moment of inertia J of spindle motor rotor _e, main shaft i transmission link is to the ratio of gear j of motor output shaft _i, the equivalent moment of inertia J of each parts of i transmission link _i, transmission link number m.

The computing formula of main shaft Spin-up power is:

P _SRA(t)=P _SR(n)+J _sα _Mω _M。

Wherein, axis system equivalence is to the moment of inertia J of machine shaft _sfor fixed value and by calculation of design parameters, obtain.

According to Machine Tool design data, obtain AH gear main shaft to the ratio of gear u=0.6952 of motor output shaft, the basic frequency f of spindle inverters _bA=50Hz, spindle motor magnetic pole logarithm p=2, the acceleration time t of spindle inverters _a=2.8s.According to above design parameter, calculate the speed of mainshaft n(unit of main shaft Spin-up process: rpm)

$n=n_1+\frac{{60\mathrm{uf}}_{\mathrm{BA}}t}{{\mathrm{pt}}_A}=n_1+372.43t---\left(2\right)$

Wherein, n ₁be the initial speed of mainshaft before main shaft Spin-up, unit is rpm; T is the time of main shaft Spin-up, and unit is s.

Spindle motor angular velocity omega _m(unit: rad/s) obtained by following computing formula:

${\mathrm{\&omega;}}_M=\frac{2\mathrm{\&pi;}{n}_1}{60u}+\frac{2\mathrm{\&pi;}{f}_{\mathrm{BA}}t}{{\mathrm{pt}}_A}=0.1506n_1+56.10t---\left(3\right)$

Spindle motor angular acceleration _maccording to following computing formula, obtain:

${\mathrm{\&alpha;}}_M=\frac{{2\mathrm{\&pi;f}}_{\mathrm{BA}}}{{\mathrm{pt}}_A}=56.10\mathrm{rad}/s^2---\left(4\right)$

Spindle angular acceleration alpha obtains according to following computing formula:

$\mathrm{\&alpha;}=\frac{{2\mathrm{\&pi;uf}}_{\mathrm{BA}}}{{\mathrm{pt}}_A}=39.00\mathrm{rad}/s^2---\left(5\right)$

Analyzing numerically controlled lathe CK6153i transmission system for spindle box figure is known, and this numerically-controlled machine AH driving-chain comprises 5 transmission links, and the ratio of gear of each transmission link is respectively j ₂=1, j ₃=150/165=0.9091, j ₄=j ₃* 39/51=0.6952, j ₅=j ₄* 44/44=0.6952.The moment of inertia of each transmission link is respectively J ₂=0.016327kgm ², J ₃=0.039037kgm ², J ₄=0.028138kgm ², J ₅=0.50402kgm ².Spindle motor rotor moment of inertia obtains according to design of electrical motor data, J _e=0.0296kgm ².According to above design parameter, calculate axis system equivalence to the moment of inertia J of machine shaft _s:

$J_s=J_e+\underset{i=2}{\overset{m}{\mathrm{\&Sigma;}}}{j}_i^2{J}_{i=0.3354\mathrm{kg}\&CenterDot;m^2---\left(6\right)}$

The speed of mainshaft n that above formula is calculated and spindle motor angular velocity omega _mexpression formula, and spindle motor angular acceleration _m, the equivalence of spindle angular acceleration alpha and axis system is to the moment of inertia J of machine shaft _svalue be updated in main shaft Spin-up power equation, obtain main shaft Spin-up power P _sRA

P _SRA(t)=P _SR(n ₁+372.43t)+2.83n ₁+1055.57t (7)

The spindle angular acceleration alpha that above formula is calculated, the initial speed of mainshaft n before main shaft Spin-up ₁final speed of mainshaft n while completing with main shaft Spin-up ₂be updated in main shaft Spin-up equation of time, obtain main shaft Spin-up duration t _sRA

$t_{\mathrm{SRA}}=\frac{2\mathrm{\&pi;}(n_2-n_1)}{60\mathrm{\&alpha;}}=0.002685(n_2-n_1)---\left(8\right)$

According to P _sRAand t (t) _sRA, obtain main shaft Spin-up energy consumption E _sRAcomputing formula:

$E_{\mathrm{SRA}}={\&Integral;}_0^{t_{\mathrm{SRA}}}{P}_{\mathrm{SRA}}\left(t\right)\mathrm{dt}---\left(9\right)$

So just, obtained the computing formula of numerically-controlled machine CK6153i AH driving-chain main shaft Spin-up power and energy consumption, thereby according to the speed of mainshaft n of input ₁and n ₂, calculate main shaft Spin-up power and energy consumption.

Below the accuracy of computing formula gained main shaft Spin-up power and energy consumption is verified.Choose at random the initial speed of mainshaft n before main shaft Spin-up ₁final speed of mainshaft n while completing with main shaft Spin-up ₂, forming four checking group experiments, parameter is as shown in table 2.

Table 2

The power of checking group main shaft Spin-up process and energy consumption calculation value and measured value are analyzed, and the predicted power of four checking group main shaft Spin-ups and measured power contrast are as shown in Figure 4.For energy consumption, by accuracy computation formula: feasibility and the validity of checking the method, wherein, energy consumption calculation value, it is energy consumption measurement value.The energy consumption calculation value of four checking group main shaft Spin-ups and measured value contrast are as shown in table 3.

Table 1

By above-mentioned experiment contrast, find, the main shaft Spin-up predicted power curve that application the inventive method obtains is very identical with measured power curve, and energy consumption precision of prediction is all more than 85%.Therefore, the inventive method can obtain main shaft Spin-up power and energy consumption more accurately for prediction, and result of calculation can be directly used in lathe energy consumption assessment.

After obtaining the computing formula of main shaft Spin-up power and energy consumption, enter step 3.

Step 3, set the initial speed of mainshaft and the final speed of mainshaft of main shaft Spin-up, change the acceleration time of spindle inverters, be updated to the computing formula of main shaft Spin-up power and energy consumption, calculate the different values of main shaft Spin-up power peak and energy consumption.

The numerically-controlled machine CK6153i AH driving-chain of take is example, provides the acceleration time t of three kinds of optional spindle inverters _athe plan of establishment, the t of scheme 1, scheme 2 and scheme 3 parameter of giving _avalue is respectively 2.8 _s, 2.0 _swith 1.2 _s.

In the current embodiment of the present invention, the set initial speed of mainshaft is 0, and the final speed of mainshaft is maximum principal axis rotating speed, is 1500rpm in current embodiment.According to step 1, to 3, calculate main shaft Spin-up power and the energy consumption of three design proposals as shown in table 4:

Table 4

Step 4, according to the different values of main shaft Spin-up power peak and energy consumption, control the acceleration time that main shaft of numerical control machine tool system arranges suitable spindle inverters, selection makes main shaft Spin-up power peak be less than default power upper limit value and energy consumption reaches minimum.

Selected main shaft Spin-up power upper limit value P _u=10000W, the main shaft Spin-up peak power of scheme 3 is 11314W, has surpassed the power upper limit allowing, and does not meet Machine Tool design demand.Contrast remaining scheme 1 and scheme 2, the acceleration time of scheme 2 is shorter, and energy consumption is lower, and wherein scheme 2 is than the main shaft Spin-up time decreased 27.5% of scheme 1, and Energy Intensity Reduction 4.4%, preferentially selects lathe scheme 2.

In actual process, can control the acceleration time that axis system is selected most suitable spindle inverters, thereby reach energy-conservation object.

Finally explanation is, above case study on implementation is only unrestricted in order to technical scheme of the present invention to be described, technical scheme of the present invention is modified or replaced on an equal basis, and do not depart from aim and the scope of the inventive method, it all should be encompassed in the middle of claim scope of the present invention.

Claims (9)

1. obtaining and an energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption, is characterized in that, comprises the steps:

Step 1, controls main shaft with different speed of mainshaft rotations, and obtains main shaft rotary power equation P _sR(n), wherein n is the speed of mainshaft;

Step 2, obtains the design parameter of main shaft, according to main shaft rotary power equation and design parameter, obtains main shaft Spin-up power P _sRA(t) computing formula, and further obtain the computing formula of energy consumption, the computing formula of main shaft Spin-up power is:

P _SRA(t)=P _SR(n)+J _sα _Mω _M，

Wherein, t is the time, and span is at [0, t _sRA], t _sRArepresent the main shaft Spin-up duration, J _sthat axis system equivalence is to the moment of inertia of machine shaft, α _mspindle motor angular acceleration, ω _mbe spindle motor angular velocity, and spindle motor angular acceleration and spindle motor angular velocity change with the variation of the acceleration time of spindle inverters;

Step 3, set the initial speed of mainshaft and the final speed of mainshaft of main shaft Spin-up, change the acceleration time of spindle inverters, be updated to the computing formula of main shaft Spin-up power and energy consumption, calculate the different values of main shaft Spin-up power peak and energy consumption;

Step 4, according to the different values of main shaft Spin-up power peak and energy consumption, controls the main shaft of numerically-controlled machine, selects the acceleration time of suitable spindle inverters, makes main shaft Spin-up power peak be less than default power upper limit value and energy consumption reaches minimum.

2. obtaining and energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption as claimed in claim 1, is characterized in that, obtains main shaft rotary power equation P in step 1 _sR(n) method is as follows:

Step 1-1, lathe standby power P when measurement main shaft is static _sO;

Step 1-2, sets the interval that the speed of mainshaft increases progressively, and controls the speed of mainshaft and with the interval setting, increases progressively between maximum principal axis rotating speed zero, is rotated, and obtains the main shaft rotary power of the corresponding speed of mainshaft;

Step 1-3, take speed of mainshaft n as independent variable, main shaft rotary power P _sRfor dependent variable, by the regretional analysis of segmentation once linear, obtain main shaft rotary power equation.

3. obtaining and energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption as claimed in claim 2, it is characterized in that, in step 1-3, the method that obtains main shaft rotary power equation by the regretional analysis of segmentation once linear is, take the speed of mainshaft as horizontal ordinate, main shaft rotary power is ordinate, draws the functional arrangement of main shaft rotary power, and observing and obtaining the most obvious two the some horizontal ordinates of slope variation is n _p1and n _p2, at n ∈ (0, n _p1], n ∈ (n _p1, n _p2] and n ∈ (n _p2, n _max] each interval range in, take n as independent variable, P _sRfor dependent variable, carry out once linear regretional analysis, gained main shaft rotary power equation is piecewise function, wherein n _maxit is the main shaft rotation maximum (top) speed of setting.

4. obtaining and energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption as claimed in claim 1, is characterized in that, the computing formula of speed of mainshaft n is:

Wherein, n ₁for the initial speed of mainshaft, u is that main shaft is to the ratio of gear of motor output shaft, f _bAfor the basic frequency of spindle inverters, p is spindle motor magnetic pole logarithm, t _afor the acceleration time of spindle inverters.

5. obtaining and energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption as claimed in claim 1, is characterized in that, axis system equivalence is to the moment of inertia J of machine shaft _scomputing formula be:

Wherein, J _efor the moment of inertia of spindle motor rotor, j _ifor the ratio of gear of i transmission link of main shaft to motor output shaft, J _ibe the equivalent moment of inertia of each parts of i transmission link, m is transmission link number.

6. obtaining and energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption as claimed in claim 4, is characterized in that spindle motor angular acceleration _mcomputing formula be:

7. obtaining and energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption as claimed in claim 4, is characterized in that spindle motor angular velocity omega _mcomputing formula be:

8. obtaining and energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption as claimed in claim 4, is characterized in that, the computing formula of energy consumption is:

Wherein, t _sRAcomputing formula as follows:

Wherein, n ₂for the final speed of mainshaft, α is spindle angular acceleration.

9. obtaining and energy-saving control method of the main shaft Spin-up power of numerically-controlled machine and energy consumption as claimed in claim 8, is characterized in that, the computing formula of spindle angular acceleration alpha is as follows: