CN100384082C - Method and apparatus for controlling AC induction motor energy-saving operation - Google Patents

Abstract

The present invention relates to a method and an apparatus for controlling energy-saving operation of an AC induction motor. The operation of a motor is controlled by an energy-saving control module and a large-power frequency modulation and voltage regulation module which are arranged in the present invention; the energy-saving control module gives control signals of rotation speed according to requirements of objects driven by a motor, and the increment of input electric energy for the motor is calculated in interval of each sampling period; an output control parameter which satisfies the basic operation requirements of the objects driven by the motor in the following sampling period is calculated according to the increment; the motor enters an operation start point under the given speed through the control of frequency modulation and voltage regulation; then, a control parameter automatically carries out regulation according to a given search strategy, and the input energy of the motor trends to be the least through the control of frequency modulation and voltage regulation. The present invention has the advantages that on the premise that the operation requirements of the objects driven by the motor are satisfied, the method and the apparatus for controlling energy-saving operation of an AC induction motor can automatically ensure the controlled motor to operate under the state of low power consumption as much as possible through the control of speed regulation and voltage regulation all the time, and the energy-saving effect can be obtained as good as possible under any condition of normal operation.

Description

AC induction motor energy-saving progress control method and device

Technical field

The present invention relates to the control of motor operation, relate in particular to the energy-saving control method and the device of induction alternating current (AC) motor.

Background technology

At present, in energy saving motor control technology field, the energy-conserving control technology of conventional motor is followed the development of motor itself, has formed following two kinds of mainstream technologys: variable-frequency speed-adjusting energy-saving control technology and synchronous pressure regulating energy-saving control technology.

The maximum characteristics of variable-frequency speed-adjusting energy-saving control technology are: when motor drags object can be consuming time by changing that rotating speed reduces, regulate motor speed and reach energy-conservation purpose through changing supply frequency, energy-saving effect is to determine and controlled.Its main foundation is N=(1-S) * 60f ₁The motor speed of this affirmation of/p----supply frequency characteristic relation.The variable-frequency speed-adjusting energy-saving control technology only is applicable to the adjustable speed system, and is dragged object itself possesses direct relation with rotating speed energy dissipation condition.What save mainly is the meritorious energy of system's waste, can not save the energy of motor own loss.The Energy Saving Control face is narrower.

Synchronously the maximum characteristics of pressure regulating energy-saving control technology are: because load factor, motor self-characteristic that the efficient of motor and supply voltage, motor move and drag object service conditions etc. indirect relation is arranged, with regard to ordinary circumstance, to speed do not change electric motor system under the lower prerequisite of induction-motor load rate, suitably turn down supply voltage synchronously and can reduce motor own loss acquisition energy-saving effect, and mainly be to save reactive loss.Typical method based on these characteristics has: power factor (PF) is followed the tracks of pressure regulation, motor efficiency is followed the tracks of technology such as pressure regulation, electric current variation tracking pressure regulation.But owing to there is not quantitative relationship accurately between the Energy Saving Control of these technology foundation and the motor actual consumption.Energy-saving effect is uncertain.The actual energy-saving effect of difficult acquisition during use.Particularly this method can not be saved the waste of energy that drags object, and the Energy Saving Control ability is very limited.

From existing technology and the Related product that is used for conventional energy saving motor operation control:

The variable-frequency speed-adjusting energy-saving control technology only possesses the Energy Saving Control effect to the adjustable speed system.Energy-saving effect is controlled, saving be the energy of system waste.But aspect energy-saving application, can only be used for the adjustable speed system.

Synchronously the pressure regulating energy-saving control technology can only solve energy saving motor control problem under the lower prerequisite of induction-motor load rate qualitatively by indirect parameter, does not possess definite energy-conservation controllability.Energy-saving effect, the saving of especially meritorious energy can not effectively be guaranteed.And can only be used for not changing the object of motor speed.

As seen, the substantive issue of energy saving motor operation control is: satisfying under the prerequisite that motor drags the object service requirement, make the input power of motor reach minimum, and prior art does not provide the solution of this problem.

Summary of the invention

The technical problem to be solved in the present invention is to avoid above-mentioned the deficiencies in the prior art part, and proposes a kind ofly satisfying under the prerequisite that motor drags the object service requirement, makes the input power of motor reach minimum Energy Saving Control and realizes approach.

The technical scheme that the present invention solves the problems of the technologies described above employing is, a kind of AC induction motor energy-saving progress control method is proposed, by the operation of energy-saving control module and high-power frequency voltage regulating module control motor is set, energy-saving control module drags the requirement of object according to motor, provide speed controling signal, and each in sampling period at interval in the input electric energy increment of calculating motor, according to this increment, calculate and satisfy the output Control Parameter that motor drags the basic service requirement of object in next sampling period, by frequency modulation and Regulation Control, operation starting point when making motor enter given rotating speed, again by given search strategy, automatically regulate Control Parameter,, make the motor intake be tending towards minimum through frequency modulation and Regulation Control.

As seen, control method of the present invention is to be based upon on two important feature of motor to the economize on electricity control of motor: a. frequency adjustment can be controlled the rotating speed of motor; B. suitable Regulation Control can reduce the loss of motor.

In control method of the present invention, given motor speed and the optimum output of search controlled quentity controlled variable are the committed steps to energy saving motor control, and the calculating of control voltage increment is to guarantee that motor normally moves the primary condition of control.

Further, the technical scheme that the present invention solves the problems of the technologies described above employing also comprises, manufacture a kind of AC induction motor energy-saving operating control device, comprise power circuit and measure the instrument transformer that electric current is used, also comprise energy-saving control module and high-power frequency voltage regulating module, described energy-saving control module comprises signaling conversion circuit, operating parameter setting circuit and microprocessor;

The input signal of signaling conversion circuit comprises that induction alternating current (AC) motor drags the speed controling signal of object, extraneous power source voltage and electric current, motor input voltage and motoring signal, the signal after described signaling conversion circuit is handled send microprocessor; The operating parameter setting circuit comprise link to each other with microprocessor drag the button and the indicating device of the basic service requirement parameter of object in order to input motor, perhaps in order to import the communication interface of described operational factor; The output signal of described microprocessor comprises the driving to the high-power frequency voltage regulating module, and extraneous AC power is powered to induction alternating current (AC) motor through described high-power frequency voltage regulating module; Described energy-saving control module drags the requirement of object according to motor, provide speed controling signal, and each in sampling period at interval in the input electric energy increment of calculating motor, according to this increment, calculate and satisfy the output Control Parameter that motor drags the basic service requirement of object in next sampling period, by frequency modulation and Regulation Control, operation starting point when making motor enter given rotating speed, again by given search strategy, automatically regulate Control Parameter, through frequency modulation and Regulation Control, make the motor intake be tending towards minimum.

In the embodiment of control method of the present invention and device, preferably, the step that described energy-saving control module is carried out comprises:

A, variable speed energy saving control: the speed governing parameter is determined in the requirement that drags object according to motor, provide speed controling signal by variable speed energy saving process able to programme according to the speed governing parameter of setting, perhaps when not needing the object feedback, can provide the tach signal that is fixed on the working point that needs by manual adjustments, and guarantee that by speed closed loop control the actual speed of motor meets to provisioning request; Interrupt step b when the increment absolute value according to the given rotating speed signal surpasses set point, new initial input supply frequency and the input voltage of while calculation control motor, the control motor changes step b then, otherwise carries out the circulation of step a by new given rotating speed value operation;

B, pressure regulating energy-saving control: the new initial input voltage of the motor that provides of a set by step, the operation of control motor; Automatically measure the extraneous AC power cycle subsequently, and with this as the sampling period, sampling motor virtual voltage, extraneous AC supply voltage and electric current, the input electric energy increment of calculating in current sampling period interval, again by given energy-conservation search strategy, calculate and the adjusting motor voltage, make motor operate in minimum input energy state.

Among the step a, described variable speed energy saving process able to programme, can drag the corresponding relation between object running status and motor speed according to the motor that the reality requirement is set, monitor the operating state signal that motor drags object automatically, provide the corresponding rotating speeds control signal.

Among the step a, described speed closed loop control is by dragging the controlled parameter feedback signal of object, the closed-loop control system that given rotating speed control signal and tolerance control algolithm constitute realizes, when dragging the controlled parameter drift-out set-point of object operation with closed ring when surpassing the limit of setting, on the contrary the open loop operation.

Step a and step b are respectively independent the execution, but whether step a surpasses the limiting parameter of setting by the increment absolute value of judging tach signal, and coming provides initial value and interruption/return control for step b.

Among the step b, if motor is a three-phase, motor virtual voltage, extraneous AC supply voltage are that the hypothesis three phase sine exchanges the power supply of balance power supply with electric current, and only to wherein a phase supply voltage and electric current are measured.

Among the step b, described energy-conservation search strategy, be whether to judge motor near the minimum energy dissipation running status according to the positive and negative variation of electric energy increment, the electric energy increment reduces the motor output voltage when being negative, when the electric energy increment represents to search the optimal control point by negative change timing;

In the described energy-conservation search strategy, comprise one in order to guarantee when turn down the motor supply power voltage, to cause that rotating speed reduces the motor speed that can not surpass the limit of setting and changes the input electric energy increment magnitude variations that restriction turn to control and in time to follow the tracks of the variation of induction-motor load in order to the assurance search procedure and turn to control.

Described motor speed changes restriction and turns to control to be: when the absolute value of given rotating speed and actual speed difference during greater than the limiting parameter of setting, the control of expression pressure regulating energy-saving has reached boundary value, be multiplied by the voltage increment that calculates by the given step-length coefficient that returns, increase the motor output voltage.

Described input electric energy increment magnitude variations turns to control to be: when the electric energy increment greater than when equalling zero, if the absolute value of electric energy increment is greater than the Control Parameter of setting, the input power that expression drags load needs to follow the tracks of fast to increase, add the voltage increment that calculates by given initial voltage, regulate the motor output voltage, otherwise, uncomfortable economize on electricity motivation output voltage; When the electric energy increment is less than zero the time, if the absolute value of electric energy increment is greater than the Control Parameter of setting, the input power that expression drags load can be followed the tracks of fast and be reduced, by the voltage increment that calculates, reduce the motor output voltage, otherwise, be multiplied by the voltage increment that calculates by given step-size in search coefficient, reduce the motor output voltage.

Compare with prior art, adopt AC induction motor energy-saving progress control method of the present invention and device, can guarantee automatically that controlled motor operates in the least possible power consumption state all the time, all can obtain energy-saving effect as well as possible under any normal running (operation) conditions.

Description of drawings

Fig. 1 is an induction alternating current (AC) motor equivalent-simplification circuit diagram.

Torque when Fig. 2 is the induction alternating current (AC) motor Regulation Control, rotating speed, voltage relationship figure.

Fig. 3 is the theory diagram of AC induction motor energy-saving progress control method of the present invention.

Fig. 4 is the flow chart of the variable speed energy saving control of control device execution of the present invention.

Fig. 5 is the flow chart of the pressure regulating energy-saving control of control device execution of the present invention.

Fig. 6 is the electrical schematic diagram of AC induction motor energy-saving operating control device embodiment of the present invention.

Embodiment

Be described in further detail below in conjunction with the most preferred embodiment shown in the accompanying drawing.

The theory diagram of AC induction motor energy-saving progress control method of the present invention shown in Figure 3, expressed the essential structure of whole system, whole system comprises power circuit and measures the instrument transformer that electric current is used, also comprise two functional modules: control module 10 and power model 20, extraneous AC power is through 30 power supplies of 20 pairs of induction alternating current (AC) motors of described power model, to drag load 40 work.Motor consumption detection line VL1, VL2, VL3, IL1 and Vu are connected to outside input power cord L1, current converter I1 and motor input power cord Vu in signal input in the control module 10 and the converting unit 11, control incoming line S1, S2 are connected to rotational speed setup signalling and outside speed closed loop feedback control signal line, as can also be seen from Figure from the feedback signal of motor 30 object that drags 40, provided the work state information that drags object 40, switched thereby energy-saving control module 10 can carry out rotating speed according to these status signals.Also comprise in the control module 10 the operating parameter setting circuit comprise link to each other with microprocessor drag the button and the indicating device of object 40 operational factors in order to input, perhaps in order to import the communication interface of described operational factor, thereby can carry out parameter setting and other data communication by external equipment in accordance with communications protocol such as MOBUS, perhaps when not needing the object feedback, can provide the tach signal that is fixed on the working point that needs by manual adjustments.Signal processing in the control module 10, computing and controlled quentity controlled variable output unit 12 are a slice high-performance microprocessors, select for use model to be: the MSP430133 of TI company, have a serial communication interface above it, built-in A/D converter port A1-A5 is connected to the respective signal line of unit 11, output port OU1, OU2 in the chip; OV1, OV2; OW1, OW2 are connected to the drive signal line of high-power frequency pressure regulation power model 20.Power model 20 incoming line L1, L2, L3 connect outside input power cord, and output line U, V, W connect the motor input power cord.

Fig. 6 circuit is the concrete electrical schematic diagrams of implementing of apparatus of the present invention.By button and the indicating device that links to each other with microprocessor, perhaps can drag the setting of object 40 operational factors by the RS485 communication interface.After isolation processing, send microprocessor by dragging speed controling signal and the status signal that object 40 feeds back.Signaling conversion circuit 11; isolate three-phase phase voltage by dividing potential drop from outside three-phase input power cord voltage; construct reference zero; and obtain the zero-crossing pulse signal of three-phase phase voltage by comparator circuit, the sampling time benchmark is provided for the A/D conversion of phase voltage and to the open-phase protection control of three phase mains.A phase supply voltage, A phase current, U phase motor voltage, artificial given rotating speed signal S1 and closed loop input speed signal S2 are converted to the input signal that is fit to A/D conversion requirement in the microprocessor sheet through operational amplifier and peripheral circuit.Because three phase mains is the balance sine power supply, simplify circuit resource and improve arithmetic speed for making, only adopt the A phase signals to carry out data processing.Microprocessor by suitable computing, obtains optimum Energy Saving Control data according to these signals, and these data is converted to three pairs of PWM drive signals of control high-power frequency pressure regulation power model.High-power frequency pressure regulation power model is the general utility functions module, and this module is exported the high-power pwm power drive signal of three-phase under the control of three pairs of PWM drive signals, promotes motor by optimum energy saver mode operation.

The program of microprocessor is by the algorithm establishment of describing in the summary of the invention, Fig. 4 is a main flow, it also is the flow process of variable speed energy saving control, as seen, it at first is the speed controling signal that drags object according to motor, whether the change in rotational speed amount of judging load request surpasses set point, it is the flow process of then interrupting/stopping the current pressure regulating energy-saving control that may move, step b just, and carry out: the frequency and the motor input voltage of calculating motor input power supply, press calculated value and adjust the frequency of motor input power supply by described power model, compare the calculated value of motor input voltage and the actual input voltage of current motor, if calculated value, is pressed the input voltage of calculated value by described power model adjustment motor greater than actual value, change step b.Fig. 5 is the flow process of pressure regulating energy-saving control, as seen, it is that self-loopa is carried out, measure actual input voltage, the voltage of extraneous AC power, the electric current of motor in real time, according to the formula of in summary of the invention, describing, the input electric energy increment of calculating motor in current sampling period interval, increment size with the optimal value search of the input voltage of motor, then, judge the input electric energy increment situation in this sampling period, adjust the actual input voltage of motor.

Wherein, relevant calculating, the algorithm of foundation is described as follows:

Able to programmely be provided with 3 input ports, represent 8 input states, respectively corresponding 8 output speeds.

SIN(i)＝ST(i)

In the formula: ST (i) is the input state transfer algorithm, can be to table look-up, and SIN (i) is corresponding output speed, and i is the 1-8 sequence number.

By the rotating speed SIN of load request, calculate frequency and motor input voltage f0, the Vo of motor input power supply:

fo＝KfSIN

Kf in the V0=Kvfo formula, Kv are constant

Gather power supply input current, voltage With the motor input voltage By formula:

$A_{\mathrm{IN}}\left(T\right)=3\frac{T}{N}\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{\stackrel{\·}{I}}_{\mathrm{AINi}}\×{\stackrel{\·}{U}}_{\mathrm{AINi}};({\stackrel{\·}{I}}_{\mathrm{AINi}}\×{\stackrel{\·}{U}}_{\mathrm{AINi}}>0)$

$R_{\mathrm{IN}}\left(T\right)=3\frac{T}{N}\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{\stackrel{\&CenterDot;}{I}}_{\mathrm{AINi}}\&times;{\stackrel{\&CenterDot;}{U}}_{\mathrm{AINi}};({\stackrel{\&CenterDot;}{I}}_{\mathrm{AINi}}\&times;{\stackrel{\&CenterDot;}{U}}_{\mathrm{AINi}<=}0)$

$U_{\mathrm{IN}}\left(T\right)=\sqrt{\frac{T}{N}\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{\stackrel{\&CenterDot;}{U}}_{\mathrm{Di}}\&times;{\stackrel{\&CenterDot;}{U}}_{\mathrm{Di}}}$

In the formula, the sampling number of data among power cycle T of N, span: 2-1000.

Calculate meritorious in the power cycle T, reactive energy and motor voltage effective value: I _AIN, U _AIN, U _IN(T).

Power change increment Delta A in power cycle T of following calculation _IN=A _INi+I(T)-A _INi(T)

The formula of calculation control voltage increment:

$\mathrm{\&Delta;U}=\frac{\mathrm{\&Delta;}{A}_{\mathrm{IN}}\left(T\right)}{2K{U}_{\mathrm{IN}}\left(T\right)}$

In the formula:

K＝T?Pe/U ²e

Wherein:

Voltage decrease when a Δ U is each step search least energy consumption, wherein a is the step-size in search coefficient, usually according to the desirable 0.1-1 of system response time speed.

B Δ U is the recruitment that reaches search voltage during boundary value, and wherein b is for returning the step-length coefficient, get a usually 0.1-0.5 times.

E is that electric energy increment magnitude variations turns to Control Parameter, the 5%-20% of span rated power.

E s is that the velocity variations restriction turns to control limiting parameter, the 1%-10% of span rated speed.

Wherein, parameter a, b, e and es all are by the operating parameter setting circuit, are provided with through variable speed energy saving process able to programme.

The basic foundation of the above-mentioned algorithm of the present invention further specifies as described below:

At given rotating speed, under the given supply frequency state, motor can be obtained by motor equivalent-simplification circuit shown in Figure 1 when operate as normal:

The power equivalent equation

P ₁＝P _M+P _cu1+P _fe1

P _M＝P ₂+P _cu2+P _a

In the formula: power input to machine: P ₁

Stator copper loss: P _Cu1=m ₁I ₁ ²R ₁=Z ₁(s) ²m ₁R ₁U ₁ ²

Stator iron loss: P _Fe1=m ₁I _m ²R _m=Z _m(s) ²m ₁R _mU ₁ ²

Electromagnetic power: P _M=Ω ₁M (Ω ₁: desirable unloaded angular speed)

Mechanical output: P ₂

Copper loss of rotor: ${\mathrm{<figure-callout\; id="2"\; label="P\; cu"\; filenames="C20051010094200171.png"\; state="\{\{state\}\}">P</figure-callout>}}_{\mathrm{cu}}=m_1{I}_2^{\&prime;2}{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="C20051010094200171.png"\; state="\{\{state\}\}">R</figure-callout>}}_2^{\&prime;}=Z_2{\left(s\right)}^2{m}_1{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="C20051010094200171.png"\; state="\{\{state\}\}">R</figure-callout>}}_2^{\&prime;}{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="C20051010094200131.png"\; state="\{\{state\}\}">U</figure-callout>}}_1^2$

Supplementary load loss: P _a

This shows: the variation of motor input voltage U1 can change the running wastage of motor.

The electromagnetic torque equation: $M=\frac{1}{{\mathrm{\&Omega;}}_1}\frac{m_1{\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="C20051010094200131.png"\; state="\{\{state\}\}">U</figure-callout>}}_1^2\frac{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="C20051010094200171.png"\; state="\{\{state\}\}">R</figure-callout>}}_2^{\&prime;}}{s}}{{({\mathrm{<figure-callout\; id="1"\; label="R"\; filenames="C20051010094200131.png"\; state="\{\{state\}\}">R</figure-callout>}}_1+\frac{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="C20051010094200171.png"\; state="\{\{state\}\}">R</figure-callout>}}_2^{\&prime;}}{S})}^2+{({\mathrm{<figure-callout\; id="1"\; label="X"\; filenames="C20051010094200131.png"\; state="\{\{state\}\}">X</figure-callout>}}_{1\mathrm{\&sigma;}}+{\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="C20051010094200171.png"\; state="\{\{state\}\}">X</figure-callout>}}_{2\mathrm{\&sigma;}}^{\&prime;})}^2}=Z_M\left(s\right){\mathrm{<figure-callout\; id="1"\; label="U"\; filenames="C20051010094200131.png"\; state="\{\{state\}\}">U</figure-callout>}}_1^2$

Change motor input voltage U1 by the electromagnetic torque equation, can obtain characteristic curve shown in Figure 2.At given rotating speed, during given supply frequency,, reduce the normal operation that motor input voltage Ul does not influence electric system as long as load and mechanical loss torque sum M1 be the maximum output torque Mmax during less than given input voltage.

Therefore, can derive at given rotating speed by above-mentioned motor fundamental equation, during given supply frequency, the approximate expression of power input to machine:

P ₁=Z _M(s)U ₁ ²

When revolutional slip changes hour, the available constant P e/Ue of ZM (s) ²The approximate replacement.

In a power cycle T time:

A _IN(T)=TP ₁

U _IN(T)=U ₁

That is:

A _IN(T)=K?U _IN(T) ²

K＝T?Pe/U ²e

Obtain after getting increment:

$\mathrm{\&Delta;U}=\frac{\mathrm{\&Delta;}{A}_{\mathrm{IN}}\left(T\right)}{2K{U}_{\mathrm{IN}}\left(T\right)}$

This relational expression be controller at given rotating speed, under the given supply frequency, optimal control provides basic starting point to energy saving motor.

The rotating speed equation of motor

S _IN=(1-s) in the 60fo/p formula: s is a revolutional slip: p is that number of pole-pairs provides the control foundation for variable speed energy saving control.

And, make:

In the Vo/fo=Ve/fe=Kv formula: Ve is the motor rated voltage, fe motor rated frequency

With assurance motor security of operation,

The control program that is based upon on the essential characteristic of these two motor is searched for by energy saving optimizing, has realized the present invention to the Energy Saving Control of motor.

The technique effect that control method of the present invention and device bring is embodied in the following aspects:

1. the speed setting and the speed governing closed-loop control function that provide in inventing can provide effective Energy Saving Control for the adjustable varying-speed motor operational system:

ΔA _s＝(Se-S)M

In the formula: the Se rated speed; The S actual speed; The M load torque; Δ A _sThe motor of saving drags the energy of object waste.

2. the Regulation Control function that provides in the invention can make the Be Controlled object reduce loss under any speed conditions, and the energy saving optimizing Search Control that provides in the invention can obtain optimum accurately energy-saving effect:

ΔAv＝Σ(Ae(T)-A _MIN(T))

In the formula: the input electric energy during the no pressure regulation of Ae (T) in the average power cycle T time; Input electric energy after AMIN (T) the optimization Regulation Control in the average power cycle T time; The generator loss energy that Δ Av saves.

3. the integrated protection the when miscellaneous function that provides in inventing can realize the energy conservation starting of motor and shutdown control and operation.

4. the acquisition of above-mentioned energy-saving effect will not rely on the accurate parameters relationship of motor self and the restriction of object running status, both solve the uncertain problem in the conventional pressure regulating energy-saving control and can not save the waste that motor drags the object energy, and only can be used for the not problem of governing system, solved again in the variable-frequency speed-adjusting energy-saving control and can not save the loss of motor self-energy, and can only be used for the problem of adjustable speed system.The Energy Saving Control that can be used for any conventional motor, and, the optimum energy-saving effect and the running protection that all can obtain to determine.

Basic ideas of the present invention are: the requirement that drags object according to motor, provide speed controling signal, and each in sampling period at interval in the input electric energy increment of calculating motor, according to this increment, calculate and satisfy the output Control Parameter that motor drags the basic service requirement of object in next sampling period, by frequency modulation and Regulation Control, operation starting point when making motor enter given rotating speed, automatically regulate Control Parameter by given search strategy again, make the motor intake be tending towards minimum through frequency modulation and Regulation Control.Enforcement of the present invention is not limited to above-mentioned open embodiment.Any based on above-mentioned basic ideas, and make at the foregoing description need not creative work replacement, improvement, all belong to enforcement of the present invention.

Claims (10)

1. AC induction motor energy-saving progress control method is characterized in that:

By the operation of energy-saving control module and high-power frequency voltage regulating module control motor is set, energy-saving control module drags the requirement of object according to motor, provide speed controling signal, and each in sampling period at interval in the input electric energy increment of calculating motor, according to this increment, calculate and satisfy the output Control Parameter that motor drags the basic service requirement of object in next sampling period, by frequency modulation and Regulation Control, operation starting point when making motor enter given rotating speed, again by given search strategy, automatically regulate Control Parameter,, make the motor intake be tending towards minimum through frequency modulation and Regulation Control.

2. AC induction motor energy-saving progress control method as claimed in claim 1 is characterized in that: the step that described energy-saving control module is carried out comprises:

A, variable speed energy saving control: the speed governing parameter is determined in the requirement that drags object according to motor, provide speed controling signal by variable speed energy saving process able to programme according to the speed governing parameter of setting, perhaps when not needing the object feedback, provide the tach signal that is fixed on the working point that needs by manual adjustments, and guarantee that by speed closed loop control the actual speed of motor meets to provisioning request, interrupt step b when the increment absolute value of given rotating speed signal surpasses set point, control motor new initial input supply frequency and input voltage simultaneously, the control motor is by new given rotating speed value operation, change step b then, otherwise carry out the circulation of step a;

B, pressure regulating energy-saving control: the new initial input voltage of motor that provides of a set by step, the operation of control motor, automatically measure the extraneous AC power cycle subsequently, and with this as the sampling period, sampling motor virtual voltage, extraneous AC supply voltage and electric current calculate the input electric energy increment in current sampling period interval, again by given search strategy, calculate and the adjusting motor voltage, make motor operate in minimum input energy state.

3. AC induction motor energy-saving progress control method as claimed in claim 2 is characterized in that:

Among the step a, described variable speed energy saving process able to programme, the motor that requirement is set according to reality drags the relation between object running status and motor speed, monitors the operating state signal that motor drags object automatically, provides the corresponding rotating speeds control signal.

4. AC induction motor energy-saving progress control method as claimed in claim 2 is characterized in that:

Among the step a, described speed closed loop control, be to realize by dragging the closed-loop control system that the controlled parameter feedback signal of object, given rotating speed control signal and tolerance control algolithm constitute, when dragging the controlled parameter drift-out set-point of object operation with closed ring when surpassing the limit of setting, on the contrary the open loop operation.

5. AC induction motor energy-saving progress control method as claimed in claim 2 is characterized in that:

Step a and step b are respectively independent the execution, when step a judges that the increment absolute value of tach signal surpasses the limiting parameter of setting, for step b provides initial value and interruption/return control.

6. AC induction motor energy-saving progress control method as claimed in claim 2 is characterized in that:

Among the step b, described energy-conservation search strategy, be whether to judge motor near the minimum energy dissipation running status according to the positive and negative variation of input electric energy increment, input electric energy increment reduces the motor output voltage when being negative, when input electric energy increment represents to search the optimal control point by negative change timing;

In the described energy-conservation search strategy, comprise one in order to guarantee when turn down the motor supply power voltage, to cause that rotating speed reduces the motor speed that can not surpass the limit of setting and changes the input electric energy increment magnitude variations that restriction turn to control and in time to follow the tracks of the variation of induction-motor load in order to the assurance search procedure and turn to control.

7. AC induction motor energy-saving progress control method as claimed in claim 6 is characterized in that:

Described motor speed changes restriction and turns to control to be: when the absolute value of given rotating speed and actual speed difference during greater than the limiting parameter of setting, the control of expression pressure regulating energy-saving has reached boundary value, be multiplied by the voltage increment that calculates by the given step-length coefficient that returns, increase the motor output voltage.

8. AC induction motor energy-saving progress control method as claimed in claim 6 is characterized in that:

Described input electric energy increment magnitude variations turns to control to be: when input electric energy increment more than or equal to zero the time, if the absolute value of input electric energy increment is greater than the Control Parameter of setting, the input power that expression drags load needs to follow the tracks of fast to increase, add the voltage increment that calculates by given initial voltage, regulate the motor output voltage, otherwise, uncomfortable economize on electricity motivation output voltage; When input electric energy increment be when zero, if the absolute value of input electric energy increment is greater than the Control Parameter of setting, the quick tracking of input power that expression drags load reduces, by the voltage increment that calculates, reduce the motor output voltage, otherwise, be multiplied by the voltage increment that calculates by given step-size in search coefficient, reduce the motor output voltage.

9. an AC induction motor energy-saving operating control device comprises power circuit and measures the instrument transformer that electric current is used, and it is characterized in that:

Also comprise energy-saving control module and high-power frequency voltage regulating module, described energy-saving control module comprises signaling conversion circuit, operating parameter setting circuit and microprocessor;

The input signal of signaling conversion circuit comprises that induction alternating current (AC) motor drags the speed controling signal of object, extraneous power source voltage and electric current, motor input voltage and motoring signal, and the signal after described signaling conversion circuit is handled send microprocessor;

The operating parameter setting circuit comprise link to each other with microprocessor drag the button and the indicating device of the basic service requirement parameter of object in order to input motor, perhaps in order to import the communication interface of described operational factor;

The output signal of described microprocessor comprises the driving to the high-power frequency voltage regulating module, and extraneous AC power is powered to induction alternating current (AC) motor through described high-power frequency voltage regulating module;

Described energy-saving control module drags the requirement of object according to motor, provide speed controling signal, and each in sampling period at interval in the input electric energy increment of calculating motor, according to this increment, calculate and satisfy the output Control Parameter that motor drags the basic service requirement of object in next sampling period, by frequency modulation and Regulation Control, operation starting point when making motor enter given rotating speed, again by given search strategy, automatically regulate Control Parameter, through frequency modulation and Regulation Control, make the motor intake be tending towards minimum.

10. AC induction motor energy-saving operating control device as claimed in claim 9 is characterized in that: the performed step of the program of moving on the described microprocessor comprises:

A, variable speed energy saving control: the requirement that drags object according to motor, provide speed controling signal by variable speed energy saving process able to programme, perhaps when not needing the object feedback, provide the tach signal that is fixed on the working point that needs by manual adjustments, and guarantee that by speed closed loop control the actual speed of motor meets to provisioning request; Interrupt step b when the increment absolute value of given rotating speed signal surpasses set point, control motor new initial input supply frequency and input voltage simultaneously, the control motor changes step b then and handles, otherwise carry out the circulation of step a by new given rotating speed value operation;

B, pressure regulating energy-saving control: the new initial input voltage of the motor that provides of a set by step, the operation of control motor, automatically measure the extraneous AC power cycle subsequently, and with this as the sampling period, sampling motor virtual voltage, extraneous AC supply voltage and electric current calculate the input electric energy increment in current sampling period interval, again by given search strategy, calculate and the adjusting motor voltage, make motor operate in minimum input energy state.

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