CN2840517Y - Electric machine driving device - Google Patents

Abstract

The utility model relates to a motor drive device for detecting the load condition of a motor by using a manner of simplified sine wave drive without a sensor, wherein alternating current (1) is changed into direct current through a rectification circuit (2); a motor (4) is driven by a frequency converter circuit (3); output current of the frequency converter circuit (3) can be detected by a current detecting device (5), and under the condition of setting rotating speed, reactive current is controlled to form a specified value. In addition, the load condition can be judged by output voltage or output electrical power of the frequency converter circuit.

Description

Motor driver

Technical field

The utility model relates to a kind of motor driver that does not have the transducer sine wave drive.

Background technology

In existing this motor driver, there is not the transducer sine wave drive by saving rotor-position sensor, can reduce the vibration and the noise of motor, improve reliability (example wherein can be opened 2000-350489 number with reference to the Japanese patent gazette spy).

But, in above-mentioned existing apparatus,, need hold constant of the machine, circuit parameter or motor load in advance in order to infer the position of rotor, detect the calculated value of regulation and the error between the current measurement value; In order to make error become minimum, also need calculate by processor, therefore calculate and become very complicated, and the processor that need have the computing function of high-speed high-performance.In addition, when motor load when great changes will take place, also exist and lose the problem of (being step-out) synchronously easily.

The utility model content

The utility model is intended to solve existing middle the problems referred to above that exist, a kind of like this motor driver that does not have the transducer sine wave drive is provided, this motor driver also can stably be operated when load changes, even when for example causing output variation and step-out because of load variations, also can detect load condition and step loss condition, and carry out and restart Control Parameter or starting conditions being revised the back, and the calculating of carrying out in can simplified processor, thereby also can realize stable operation even change in load.

In order to address the above problem, motor driver of the present utility model is transformed into direct current by rectification circuit with alternating current, by the converter circuit drive motors, detect the output current of converter circuit by current sensing means, converter circuit is carried out pulse width modulation controlled makes rotating speed reach the setting rotating speed, the output voltage of converter circuit and current phase or reactive current are controlled to setting, and come load condition is judged according to the output voltage or the power output of converter circuit.

The technique effect that the utility model produces is as follows.The output voltage of the converter circuit of motor driver of the present utility model when setting rotating speed or the load condition that power output can be judged motor, can not detect step-out and load torque even do not establish position transducer yet, even also can stably realize restarting so step-out has taken place, carry out and the corresponding current settings of load, can realize also carrying out when load variations is very big the no transducer sine wave drive of stable operation.

Embodiment of the present utility model is summarized as follows.Motor driver in the 1st scheme of the present utility model is characterized in that comprising: AC power; The alternating current with described AC power that links to each other with described AC power is transformed into galvanic rectification circuit; The direct current with described rectification circuit that links to each other with described rectification circuit is transformed into the converter circuit of alternating current; The motor that drives by described converter circuit that links to each other with described converter circuit; Being used to of linking to each other with the negative voltage side of described converter circuit detected the current sensing means of the output current of described converter circuit; With with the output signal of passing through described current sensing means that described current sensing means links to each other with described converter circuit described converter circuit is carried out pulse width modulation controlled, thereby controlling described motor makes its rotating speed become the control device of set point, described control device comprises the high-speed a/d converting means that links to each other with described current sensing means, 3 phases → 2 phase standard shaft converting means link to each other with described high-speed a/d converting means, the load condition judgment means of load condition being judged from the output voltage of described converter circuit or power output with described 3 mutually → 2 phase standard shaft converting means link to each other.Like this, even load variations is very big, also can realize the no transducer sine wave drive of stable operation.

The 2nd scheme is that the control device in the 1st scheme is controlled to setting by the V/f control mode with the output voltage of converter circuit and the phase place or the reactive current of output current, and from the V/f controlling value load condition is judged.Like this, will be easy to carry out when under occasions such as step-out, rotation stop to take place rotation status being detected, the size of load also is easy to detect.

The 3rd scheme is that the control device in the 1st scheme detects the motor load state by the output voltage or the electromotive power output of converter circuit, and the output voltage of described converter circuit and the phase place or the reactive current of output current are changed.Like this, because output current phase place or reactive current can change according to load condition, even therefore load change a lot or in operating process load change, also can keep stable rotation, even and the words that step-out occurs start after torque current is increased, so can realize a kind ofly when load variations is very big, also operating, motor driver that reliability is very high.

The 4th scheme is that the control device in the 1st scheme detects the motor load state by the output voltage or the power output of converter circuit, and the motor-driven condition is changed.Like this, under the occasion that load changes in the very big and course of work in load variations, that rotation is realized is stable by changing drive conditions such as rotating speed and current of electric, perhaps reduces work noise by adjusting rotating speed.

The 5th scheme is that the control device in the 1st scheme is judged electric motor load torque by the power output and the driving frequency of converter circuit.Like this, just can realize and corresponding rotating speed control of electric motor load torque and power output control.

The 6th scheme is that the control device in the 1st scheme is judged load torque by the power output and the driving frequency of converter circuit, and according to the variation of described load torque motor is controlled.Like this, owing to, make motor stop, when underload, reducing current of electric when therefore can be implemented in overload with Optimal Control such as control rotating speeds by detecting load torque, obtaining current of electric, current phase or rotating speed that torque current just can be set the best.

The 7th scheme is, the described control device of control device in the 1st scheme is judged load torque by the power output and the driving frequency of converter circuit, and according to load torque the output voltage of described converter circuit and the phase place or the reactive current of output current is controlled.Like this, by carrying out and the corresponding current settings of load torque, can make electric efficiency reach maximum.

The 8th scheme is, the rotation abnormal conditions that output voltage or the power output of the described control device of control device in the 1st scheme by converter circuit detects motor, and after the phase place of output voltage that makes described converter circuit and output current or reactive current change, described motor is restarted.Like this, under the occasion that motor stops the rotation, can realize restarting, current settings can be become optimum state, thereby make rotation keep stable by increasing output current.

The 9th scheme is, the rotation abnormal conditions that output voltage or the power output of the described control device of the control device in the 1st scheme by converter circuit detects motor, and behind the starting conditions that changes described converter circuit, described motor is restarted.Like this, starting conditions can be set for the optimum state that adapts with load, thereby make rotation keep stable.

Description of drawings

Fig. 1 is the block diagram of the motor driver among the 1st embodiment of the present utility model,

Fig. 2 is the converter circuit figure of this motor driver,

Fig. 3 is the current detecting sequential chart of this motor driver,

Fig. 4 is the block diagram of the control device in this motor driver,

Fig. 5 is the control polar plot of this motor driver,

Control polar plot when Fig. 6 is this motor driver step-out,

Fig. 7 is various waveforms and the sequential chart in the control device of this motor driver,

Fig. 8 is the Electric Machine Control program flow diagram of this motor driver,

Fig. 9 is the flow chart of the carrier signal interruption subroutine in the Electric Machine Control program of this motor driver,

Figure 10 is the flow chart of the rotating speed control subprogram in the Electric Machine Control program of this motor driver,

Figure 11 is the starting control timing figure of this motor driver,

Figure 12 is the sectional view of the motor driver in the dish cleaning machine of the 2nd embodiment of the present utility model,

Figure 13 is the block diagram of the control device in this motor driver,

Control timing figure when Figure 14 sucks air detection for this motor driver in the drain operation process,

Control timing figure when Figure 15 sucks air detection for this motor driver in cleaning operation process,

Figure 16 is the flow chart of the rotating speed control subprogram of this motor driver,

Figure 17 is the block diagram of the control device in the motor driver of the 3rd embodiment of the present utility model,

In the above-mentioned accompanying drawing, 1 is AC power, and 2 is rectification circuit, and 3 is converter circuit, and 4 is motor, and 5 is current sensing means, and 6 is control device.

Embodiment

(embodiment 1)

Fig. 1 is the block diagram of the motor driver among the 1st embodiment.In Fig. 1, AC power 1 is added to alternating current on the rectification circuit 2, is transformed into direct current, and such direct current is transformed into 3 cross streams electricity, drive motors 4 by converter circuit 3 again.Capacitor 21a, 21b are connecting between dc output end of the full-wave rectifying circuit 20 in the rectification circuit 2, tie point between capacitor 21a, the 21b is connected with an input terminal of AC power, constitute dc voltage circuit, be added to voltage on the converter circuit 3 with raising.

The negative voltage side of converter circuit 3 is connected with current sensing means 5, and the electric current by detection is flow through in the underarm of 3 phases of converter circuit 3 detects the output current of converter circuit 3 that is each phase current of motor 4.

Control device 6 calculates the output current of converter circuit 3 from the output signal of current sensing means 5, will be applied on the drive motors 4 with the assigned voltage of setting the corresponding assigned frequency of rotating speed again, drives its rotation.Control device 6 is controlled with respect to the phase place of output voltage output current according to motor load, perhaps output current is controlled to reactive current, and drive motors 4 is rotated with the synchronizing speed of setting.

Fig. 2 is the detailed circuit diagram of the converter circuit 3 in the motor driver, wherein is provided with the 3 full wave bridge type converter circuits mutually that are made of 6 transistors and 6 diodes.For avoiding repetition, be that U phase arm 30A describes only here to 1 phase arm in 3 phase arms.Upper arm transistor 31a1 and diode 32a1 reverse parallel connection by igbt (hereinafter referred to as IGBT) constitutes form the circuit that is connected in parallel; Also be underarm transistor 31a2 and the diode 32a2 reverse parallel connection that is made of IGBT, form another circuit that is connected in parallel, these two circuit that are connected in parallel are connected in series mutually.The collector terminal of upper arm transistor 31a1 is connected with the positive potential terminal Lp of DC power supply, the emitter terminal of upper arm transistor 31a1 links to each other with lead-out terminal U, and the emitter terminal of underarm transistor 31a2 is connected with Ln terminal one side of DC power supply by the shunt resistance 50a that constitutes current sensing means 5.

Upper arm transistor 31a1 is driven according to upper arm drive signal Up by upper arm gate driver circuit 33a1, underarm transistor 31a2 is driven according to underarm drive signal Un by underarm gate driver circuit 33a2, respectively upper arm transistor 31a1 and underarm transistor 31a2 is carried out the switching controls of conduction and cut-off.The inside of upper arm gate driver circuit 33a1 is provided with the RS circuits for triggering that carry out set/reset by differential signal, rising edge by upper arm drive signal Up makes upper arm transistor 31a1 conducting, and the trailing edge that improves upper arm drive signal Up ends upper arm transistor 31a1.Need not the RS circuits for triggering in the underarm gate driver circuit.

The voltage that is applied on the grid of IGBT need reach 10～15V.When underarm transistor 31a2 conducting, bootstrap capacitor 36a is charged by bootstrapping resistance 34a, bootstrap diode 35a from the positive electrode terminal B1 of 15V DC power supply, therefore can make upper arm transistor 31a that the conduction and cut-off switching takes place by the energy that is stored among the bootstrap capacitor 36a.In addition, under the occasion of the reverse parallel connection diode 32a2 of underarm conducting, can charge to bootstrap capacitor 36a too.

The connection situation of V phase arm 30B, W phase arm 30C is with top identical, the transistorized emitter terminal of underarm in each arm is connected with the shunt resistance 50b, the 50c that constitute current sensing means 5, and the other end of shunt resistance 50b, 50c is connected with the negative terminal Ln of DC power supply.Shunting electricity is to link to each other with emitter terminal under the occasion of IGBT at transistor, is connected with source terminal under the occasion of high-power MOSFET.Adopt the words of IGBT or high-power MOSFET at the underarm transistor, owing to just can carry out switching controls by the control gate pole tension, so the voltage that the resistance of shunt resistance is selected to its two ends is being undertaken can producing any influence hardly to handover operation when conduction and cut-off is switched by voltage control below 1V.This circuit has by voltage veu, vev that detects shunt resistance and the characteristics that vew just can detect the output current that is the current of electric of converter circuit.

Fig. 3 is that the output current of converter circuit detects sequential chart, wherein carry out pulse width modulation controlled by triangular modulation, carry out the high-speed a/d conversion after the switching time of upper and lower arm IGBT staggered,, carry out current detecting by motor control processors such as microcomputers again to reduce switching noise.In Fig. 3, ck is the peak signal of triangular modulation signal Vt, that is the synchronizing signal that produces at time t3 place, vu is a U phase voltage control signal, by triangular modulation signal Vt and U phase voltage control signal vu are compared, produce drive signal Up and the U drive signal Un of underarm transistor 31a2 mutually of the upper arm transistor 31a of U phase.T1～t2 interval and t5～t6 interval be upper and lower arm transistorized non-conduction during, be known as Dead Time Δ t.May be selected in the opportunity of A/D conversion the upper arm transistor by the time t3 of, underarm transistor turns to the scope of the time t4 behind time t3 hysteresis Dead Time Δ t.

Fig. 4 is the block diagram of the control device in the utility model, is used for realizing not having the transducer sine wave drive by high speed processors such as microcomputer or digital signal processors.

Below by the control polar plot of the present utility model shown in Fig. 5 basic control method is described.Fig. 5 is provided with the polar plot of d-q coordinate system of the surperficial permanent magnet motor (be called for short SPM motor) of permanent magnet for rotor surface, wherein, motor induced voltage Vr is coaxial with the q axle, and this induced voltage Vr is directly proportional with rotational speed N (that is motor-driven frequency f) with induced voltage constant k r.In other words, the ratio between motor induced voltage Vr and the frequency f (Vr/f) is constant substantially.

Current of electric I is controlled so as to the q axle when coaxial, will be identical with vector control.But,, therefore suppose the super previous angle γ of current of electric I owing to not having rotor-position sensor, can't carrying out q repacking survey.The voltage equation of motor can represent that under the occasion that driving frequency f is fixed, when the current phasor I in the d-q coordinate system is fixed, the voltage vector Vi that is added on the motor also will be fixed with following formula 1.Conversely, when the voltage vector Vi on being added to motor was fixed, current phasor I also was fixed.In addition, transforming to when being added in the a-r axle coordinate system that voltage Vi (standard shaft) on the motor is a main shaft too, when current phasor I is fixed, motor induced voltage vector V r will be fixed.In other words, if know constant of the machine in advance, owing to just the phase control of induced voltage Vr and electric current I can be become certain by fixed current vector I, therefore can become certain to q shaft current Iq (that is torque current) basic controlling, thereby can carry out and the essentially identical control of vector control.

[formula 1]

Vi＝(R+jωL)I+Vr

Thereby reduce advance angle γ by suitable value that reactive current Isin φ is hanked, can make current of electric I and torque current (q shaft current) Iq basic identical,, reduce the loss of electric machine, reduce electric machine temperature rise, make motor realize miniaturization to increase work efficiency.

In addition, in normal operating process, by as shown in Figure 5 set current of electric I for advance angle γ like that, even because of the load variations of fierceness changes phase, also can not take place and the q axle between phase place γ be delayed, torque sharply descends, the situation of step-out occurs.Particularly, rotating speed descends suddenly, phase place γ occur to postpone with respect to the q axle and phase reaches 90 degree when above, and the possibility that step-out occurs will uprise; And can reduce the delay degree of phase place, thereby improve the stability of Spin Control by advance angle control.

In addition owing to can realize low-intensity magnetic field control (the d shaft current is for negative) by advance angle control, can reduce motor induced voltage Vr and coil winding voltage (j ω LI) with voltage vector Vo, thereby increase torque current Iq, realize high speed rotating.

As mentioned above, if known constant of the machine (winding resistance R, winding inductance L, motor induced voltage constant k r) and with the corresponding torque current Iq of motor load, only need control current of electric I with respect to the absolute value and the phase that are added to the voltage Vi on the motor, just can control the current of electric vector.In the polar plot in Fig. 5, just r shaft current Ir (=Isin φ) or a shaft current Ia (=Icos φ) that carries out from the d-q coordinate after the standard shaft coordinate conversion controlled.

In Fig. 4, drive condition setting device 60 is used for obtaining driving rotating speed, torque current, advance angle γ according to the motor-driven condition, carry out the setting of driving frequency f, reactive current Isin φ etc., and send setting signal to speed setting device 61, reactive current setting device 62.Carrier signal generating means 63 produces triangular signal Vt and the synchronizing signal ck generation that is used to carry out pulse-width modulation, and carrier frequency (switching frequency) is set at the above ultrasonic frequency of 15kHz, to reduce noise of motor.Synchronizing signal ck is sent in each computing module, and each computing module and synchronizing signal ck are synchronously operated.

In order to set the motor-driven frequency f, speed setting device 61 is obtained the phase angle Δ θ in carrier signal cycle, is added to electric phase angle and calculates on the device 64, and send the setpoint frequency signal to V/f setting device 65.The electricity phase angle is calculated device 64 and is synchronously obtained phase theta with synchronizing signal ck, this phase signal θ is added in the storing apparatus 66 that storing the standard sine table and the coordinate conversion device etc. again.

V/f setting device 65 is used for setting and driving frequency f and the corresponding voltage constant kvn that applies of load torque, with this apply voltage constant kvn be set at rotating speed or the corresponding value of load torque on.As described below, adopting single motor double water pump or single motor single water pump mode, carrying out cleaning operation when just changeing, carrying out under the occasion of drain operation when reversing, the required torque current of motor has nothing in common with each other, therefore, when rotating and reverse, need to change the set point that applies voltage constant kvn.

In the storage zone of storing apparatus 66, storing and be used to carry out calculate necessary standard sine value table, for example storing as spend from-1 to+1 sine value data from phase place 0 to 360 degree with the corresponding trigonometric function in phase angle.

Output signal veu, vev, vew to current sensing means 5 carries out the A/D conversion to high-speed a/d converting means 67 at the peak value place of the triangular modulation signal Vt shown in the sequential chart of Fig. 3, counting microsecond with the inner conversion one-tenth digital signal Iu corresponding, Iv, Iw, and the instantaneous value of each phase current is being added in 3 phases → 2 phase standard shaft converting means 68 with the frequency converter output current.

3 phases → 2 phase standard shaft converting means 68 such instantaneous value with the converter circuit output current as shown in Figure 5 carries out 3 phases → 2 phase inversion, carry out coordinate conversion to converter circuit output voltage axle that is motor standard shaft (a-r axle), concrete operations are to use following formula 2 to carry out absolute transformed, obtain a axle composition Ia and r axle composition Ir.Ir is equivalent to Isin φ, is the reactive current composition of seeing from frequency converter output (standard shaft voltage).By carrying out coordinate conversion, not only can obtain reactive current composition Ir from the output current instantaneous value in moment, can also calculate output current vector absolute value Im from the square mean formula shown in the following formula 3 in moment.In addition, can also obtain the current phase φ that sees from frequency converter output (standard shaft voltage) in moment by following formula 4, carry out phase-detection compared with the current over-zero point detection device is set, response performance can increase significantly.

[formula 2]

$\left[\begin{array}{c}\mathrm{Ir}\\ \mathrm{Ia}\end{array}\right]=\left[\begin{array}{cc}\cos \mathrm{\θ}& \sin \mathrm{\θ}\\ -\sin \mathrm{\θ}& \cos \mathrm{\θ}\end{array}\right]\×\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}1& -\frac{1}{2}& -\frac{1}{2}\\ 0& \frac{\sqrt{3}}{2}& -\frac{\sqrt{3}}{2}\end{array}\right]\left[\begin{array}{c}\mathrm{Iu}\\ \mathrm{Iv}\\ \mathrm{Iw}\end{array}\right]$

$=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}\cos & \cos (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})& \cos (\mathrm{\θ}-\frac{4\mathrm{\π}}{3})\\ -\sin & -\sin (\mathrm{\θ}-\frac{2\mathrm{\π}}{3})& -\sin (\mathrm{\θ}-\frac{4\mathrm{\π}}{3})\end{array}\right]\left[\begin{array}{c}\mathrm{Iu}\\ \mathrm{Iv}\\ \mathrm{Iw}\end{array}\right]$

[formula 3]

$\mathrm{Im}=\sqrt{{\mathrm{<figure-callout\; id="2"\; label="Ia"\; filenames="Y20052000263800321.png,Y20052000263800331.png"\; state="\{\{state\}\}">Ia</figure-callout>}}^2+{\mathrm{<figure-callout\; id="2"\; label="Ir"\; filenames="Y20052000263800321.png,Y20052000263800331.png"\; state="\{\{state\}\}">Ir</figure-callout>}}^2}$

[formula 4]

φ＝tan ^-1(Ir/Ia)

Reactive current comparison means 69 compares the 3 phases → output signal Ir of 2 phase standard shaft converting means 68 and the setting signal Irs of reactive current setting device 62, output error signal Δ ir; This error signal Δ ir amplifies calculation element 70 by error signal and amplifies or integration, outputs to the control voltage ratio than in the setting device 71 with the form that applies voltage constant change signal kv then.

The control voltage ratio is compared than the output signal kv that setting device 71 amplifies calculation element 70 with the output signal kvn and the error signal of V/f setting device 65, produce frequency converter output voltage control signal Va, make reactive current composition Ir become setting by control of conversion device output voltage.The control voltage ratio is added in 2 phases → 3 phase standard shaft inverters 72 than the frequency converter output voltage control signal Va of setting device 71 outputs.

2 phases → 3 phase standard shaft inverters 72 use the inverse transformation formula shown in the formula 5 to produce 3 phase sine voltage signals.Because frequency converter output voltage and a axle homophase, as long as therefore calculate Va, 3 mutually electric vu, vv, vw are output to impulse-width modulation control device 73.

[formula 5]

$\left[\begin{array}{c}\mathrm{Vu}\\ \mathrm{Vv}\\ \mathrm{Vw}\end{array}\right]=\sqrt{\frac{2}{3}}\left[\begin{array}{cc}1& 0\\ -\frac{1}{2}& \frac{\sqrt{3}}{2}\\ -\frac{1}{2}& -\frac{\sqrt{3}}{2}\end{array}\right]\left[\begin{array}{cc}\cos \mathrm{\&theta;}& -\sin \mathrm{\&theta;}\\ \sin \mathrm{\&theta;}& \cos \mathrm{\&theta;}\end{array}\right]\left[\begin{array}{c}\mathrm{Vr}\\ \mathrm{Va}\end{array}\right]$

$=\sqrt{\frac{2}{3}}\left[\begin{array}{cc}\cos \mathrm{\&theta;}& -\sin \mathrm{\&theta;}\\ \cos (\mathrm{\&theta;}-\frac{2\mathrm{\&pi;}}{3})& -\sin (\mathrm{\&theta;}-\frac{2\mathrm{\&pi;}}{3})\\ \cos (\mathrm{\&theta;}-\frac{4\mathrm{\&pi;}}{3})& -\sin (\mathrm{\&theta;}-\frac{4\mathrm{\&pi;}}{3})\end{array}\right]\left[\begin{array}{c}\mathrm{Vr}\\ \mathrm{Va}\end{array}\right]$

Load condition judgment means 74 is judged the motor load state by the output signal of V/f setting device 65 and error signal amplification calculation element 70 is compared.In normal operating process, almost there is not difference between the output signal kv of the output signal kvn of V/f setting device 65 and error signal amplification calculation element 70, when motor is rotated control, can make reactive current Isin φ become setting.But, under the occasion that motor generation step-out, rotation stop, motor induced voltage Vr will be shown in the polar plot among Fig. 6 become zero like that, therefore if making reactive current Isin φ is that the voltage that setting is added on the motor will reduce, the value when the output signal kvn of V/f setting device 65 and error signal are amplified difference between the output signal kv of calculation element 70 with normal running is compared and just will be seemed very big.Like this, because the output signal kvn of V/f setting device 65 is certain, the value of the output signal kv that amplifies calculation element 70 when error signal during than normal running hour just can detect stopping or rotating abnormality of motor.The restarting device 75 that abends is used for judging unusually from the output signal of load condition judgment means 74, after converter circuit 3 shut-down operations, motor being restarted.When restarting, earlier the set point of starting conditions such as the starting time of drive condition setting device 60 being set by drive condition modifier 76, starting current and reactive current Isin φ is carried out after changing again.

If motor generation step-out former is because torque current Iq deficiency, phase place occurs postponing to the q axle or phase place is too leading etc., when causing normal running or the reactive current set point Irs in when starting is too little, when causing step-out, as long as restart just passable after reactive current set point Irs changed.When starting, will become greatly, need simultaneously bigger torque current owing to will shorten brief acceleration the starting time, therefore, changing the starting time, prolonging the starting time also is a kind of selection scheme.

The sequential chart of various waveforms when carrying out pulse width modulation controlled has been shown among Fig. 7.Wherein, the motor induction voltage waveform of Eu for seeing from neutral point, Iu is the U phase current waveform, Eu comes slightly more in advance compared with the motor induced voltage.Vu, vv, vw are the pulse width modulation controlled input signal of U phase, V phase, equal each phase of W, by the output signal of 2 phases → 3 phase standard shaft inverters 72 is compared with triangular modulation signal Vt, produce pulse width modulation controlled output signal U p.Signal vu is identical with the phase place of U phase output voltage, and the phase place of U phase current Iu is than signal vu phase retardation φ.

Fig. 8 is the flow chart of the operational circumstances of the motor driver in expression the utility model.The motor-driven program drives various settings such as rotating speed, V/f, reactive current from step 100 in step 101.Next, enter step 102, judge whether to carry out start-up function; Need start if be judged to be, then enter step 103 and carry out the starting control subprogram.

Starting control subprogram 103 makes driving frequency f straight line before arriving starting time t1a rise as shown in the starting control timing figure among Figure 11, rotating speed is reached from zero set rotating speed fs, therefore need change reactive current set point Irs according to driving frequency f.At water pump and fan even load is under the occasion of fluid, torque changes with 3 powers of rotating speed, therefore wait method strictly to obtain with the corresponding torque current Iq of rotating speed, calculate Isin φ by experiment, can realize stable starting again by showing to start control.But, need quicken during owing to starting, need to increase torque current, in order to prevent step-out, reactive current set point Irs need set than big with the corresponding value of torque in addition.

In normal start-up function, V/f set point, reactive current set point Irs start under the set point of common state, also can successfully start.

When detecting under the occasion that step-out or unusual supination start again, will the starting time change into t1b, and the reactive current set point Irsa when setting reactive current set point Irsb greater than initial start, starting torque is increased.

Next, enter determination step 104 (Fig. 8) and judge have carrier-less signal to interrupt; If have carrier signal to interrupt, then carrier signal interruption subroutine in the execution in step 105 and the rotating speed control subprogram in the step 106.

Fig. 9 is the flow chart of carrier signal interruption subroutine.Program judges in step 201 from step 200 whether the count value k of carrier synchronization signal ck is the carrier number kc of motor-driven frequency f in 1 cycle; If equate, then enter step 202, make carrier wave count value k zero clearing.The carrier number kc of motor-driven frequency f in 1 cycle then obtains when setting driving frequency in advance.

For example, be that 4040 rev/mins, driving frequency f are 269.3Hz at 8 utmost point motor speeds, period T is that 3.712ms, carrier cycle Tc are under the occasion of 64 μ s (carrier frequency 15.6kHz), umber of pulse kc is 58.If when 1 cycle of driving frequency f was 2 π, the phase delta θ of 1 carrier cycle Tc was: Δ θ=2 π/kc.

In step 203, the count value of carrier synchronization signal is increased progressively, next, enter step 204, carry out the calculating of electric phase angle θ according to the phase delta θ of carrier number k and 1 carrier cycle Tc.Next, enter step 205, the signal of current sensing means 5 is detected, thereby detect frequency converter output current Iu, Iv, Iw.Next, enter step 206, carry out 3 phases → 2 phase standard shaft coordinate conversions, obtain reactive current Ir and effective current Ia by formula 2.Then, enter step 207, Ir, Ia are stored.

Next, enter step 208, obtain the vector absolute value Im of current of electric by formula 3; Next, enter step 209, judge that calculated value Im is whether more than overcurrent set point Imax.

If calculated value Im then enters step 210 on overcurrent set point Imax, the high power semiconductor component that stops to drive in the converter circuit 3 promptly stops motor-driven, and enters step 211, sets up the overcurrent abnormality sign.

If calculated value Im does not reach overcurrent set point Imax, then enter step 212, call frequency converter output control signal Va from the rotating speed control subprogram; Next, enter step 213, carry out 2 phases → 3 phase standard shaft coordinate conversions, obtain each phase control signal vu, vv, the vw of frequency converter, and enter step 214 and carry out pulse width modulation controlled according to formula 5; Then, enter step 215, return main program.

Figure 10 is the flow chart of rotating speed control subprogram.The rotating speed control subprogram needn't all be carried out each carrier signal, so for example every pair of 2 carrier signal is carried out once.When carrier frequency becomes ultrasonic frequency, the routine processes time in the carrier cycle will go wrong, therefore, can calculate phase calculation, current detecting or processing that pulse width modulation controlled etc. all must be carried out each carrier wave, with needn't the processing that each carrier wave is all carried out be separated shown in coordinate conversion and Figure 10, to not compare the processing that each carrier wave all carries out again and be divided into several batches of implementations, thus the process control block (PCB) in the dish cleaning machine beyond can actuating motor control etc.

The rotating speed control subprogram is from step 300, call driving frequency set point fs in step 301, next enter step 302, call and the corresponding reactive current set point of frequency setting value fs Irs, enter step 303 and call, enter step 304 and call and apply voltage constant set point V/f by the reactive current Ir that 3 phases → 2 phase standard shaft coordinate conversions are obtained.Next, enter step 305, Irs and Ir are compared, calculate from error signal Δ Ir and apply voltage constant kv.Next, enter step 306, calculate and apply voltage constant set point V/f and apply poor Δ kv between the voltage constant kv.Next, enter step 307, calculate standard shaft from Δ kv and apply voltage signal Va, and the Va memory is come.Next, enter step 308, Δ kv and set point Δ kvmax are compared.If Δ kv is bigger than Δ kvmax, then enter step 309, judge step-out has taken place, set up the step-out sign, enter step 310 then, make subprogram return main program.

Below, get back to the motor-driven program among Fig. 8.In step 107, judge to have or not the step-out sign, if the step-out sign is arranged, then enter step 108, motor-driven is stopped, in step 109, change reactive current Isin φ; Enter step 110 then, carry out and restart subprogram, enter step 111 at last, make the motor-driven subprogram return main program.

(embodiment 2)

Use Figure 12, Figure 13, Figure 14 and Figure 15 that the 2nd embodiment of the present utility model is described below.

Figure 12 is the motor driver sectional view of the dish cleaning machine among the 2nd embodiment of the present utility model, and what water pump here and motor adopted is single motor single water pump mode.

Wherein, running water is added to the rinse bath 7 from water intaking valve 8, and rinse water 9 stockpiles in rinse bath 7.The bottom of rinse bath 7 is provided with the dc brushless motor 4a of flat, and its rotating shaft is in vertical direction, and the bottom of motor 4a is provided with water pump cover 10.By making impeller 11 rotations, water is added from the pressure of rotating shaft towards centrifugal direction.

When impeller 11 was rotated in the forward, rinse water sprayed to the tableware (not shown) from the injection wing 12b that is provided with injection nozzle 12a, carries out cleaning operation.When just changeing, the internal pressure of pump case 10 will improve, but because the draining valve 13 that is located on pump case 10 sides is closed, water (flow) direction is towards spraying wing 12b one side.During impeller 11 reverse rotations, pressure will be added to from the side of impeller 11 on the vertical rotating shaft direction, and open draining valve 13 this moment, and the current of vertical direction will flow to drainage pipe 14 directions.Therefore, only just can realize respectively cleaning and draining with 1 motor and 1 pump.

Be provided with under the impeller and occasion pump case, single motor double water pump mode that is used for respectively cleaning with draining, also can when just changeing, clean, when counter-rotating, carry out draining, still, the problem that the height that exists pump will increase, the lower volume of rinse bath 7 can't reduce.

Under the occasion that adopts single motor single water pump mode, the non-constant of the operating efficiency of draining pump exists following two large problems.The one, in the drain operation process, will suck air after rinse water arranged, send very big noise; The 2nd, in cleaning operation process, when because foreign material block etc. former thereby when causing draining valve 13 not close fully, rinse water will be missed bit by bit, and the heater (not shown) that is used for during the rinse water light leak rinse water is heated will be in Light Condition.

In the above two kinds of cases, owing to anhydrous in the water pump, load alleviate sharp, therefore, motor is imported or load torque changes rotating speed of motor or make motor stop to replenish water inlet by detecting, and can solve the above problems.

Figure 13 is the block diagram of the control device of the motor driver among the 2nd embodiment.Basic ideas of the present utility model are, are that motor input calculates load condition or load torque by frequency converter output.Power input to machine Pin can represent that being multiplied by efficiency of motor η promptly becomes motor power output Po with frequency converter output voltage Va and current of electric I and amassing of cos φ.Efficiency of motor η is decided by rotating speed basically, and motor torque T can be represented by amassing between torque constant kt and the torque current Iq, therefore, sets up following equation 6.

[formula 6]

Po＝η·Va·Ia＝kt·ωr·Iq

That is, torque current Iq being divided into rotational speed omega r and motor input (=VaIcos φ), just can calculate by formula 6.Because Ia=Icos φ, can obtain from formula 2, even therefore do not know and the q axle between phase deviation, also can obtain motor torque by calculating.In addition, owing to torque current Iq can calculate, and the phase deviation between the q axle also can infer out conversely.

Part in the block diagram among Figure 13 is improved on the basis of Fig. 4, below these is carried out improved part and describes.And other constitutes since with the 1st embodiment in identical, its operational circumstances, effect are also identical, therefore, this just omission it is carried out repeat specification.

Voltage signal Va with 3 mutually → 2 a axis signal Ia of phase standard shaft converting means 68 be added on the electromotive power output calculation element 77 of frequency converter, calculate the input of frequency converter output that is motor; Such motor input signal and driving frequency signal f are added among the load condition judgment means 74a, calculate load torque, and the motor load state is judged.If driving frequency is certain, just can judge load variations from the motor input.Reduce load torque in order to reduce noise, when reducing rotating speed, send control signal control, tach signal is added on the drive condition setting device 60a, control setting rotating speed by drive condition modifier 78 to drive condition modifier 78.Drive condition modifier 78 not only can change the driving rotating speed, the various conditions in the time of can also changing reactive current Isin φ or starting.

The drain operation that Figure 14 shows dish cleaning machine begins the situation of change of time dependent power input to machine W in back and motor speed N.When stockpiling rinse water in the rinse bath, power input to machine is certain substantially; When rinse water has been arranged, will suck air, power input to machine and torque will sharply descend.Like this, the variation from motor input or torque can detect whether sucked air; When drain operation when output when certain value (W1) drops to setting (W3), can judge to have sucked air; Therefore, make rotating speed drop to N2, can reduce the noise when sucking air in the drain operation like this from N1 at time t3.

Power input to machine W has been shown under the occasion that the draining valve of dish cleaning machine do not cut out fully in the ongoing situation of change of cleaning among Figure 15.Make scavenging pump motor when rotation, if will suck air when having rinse water to spill in the draining valve, the load of motor will lighten.Therefore, when power input to machine becomes less than setting Wd, promptly can detect the situation that rinse water is leaked, take to stop drive motors, replenish the measure of intaking.

Figure 16 imports the embodiment of the rotating speed control subprogram of variation for detecting motor.Wherein, from step 300 to step 306a and the Figure 10 the 1st embodiment basic identical, so just be not repeated at this.In step 311, access the effective current Ia that in the carrier signal interruption subroutine, obtains, next, enter step 312 and obtain motor input Pin, enter step 313.The motor input descends, the motor input is lower than setting if determine in step 313, promptly sets up the low value sign, makes subprogram realize returning then.

When motor input decline sign is established, promptly conclude to have sucked air; If carrying out cleaning operation, motor is stopped, replenishing water inlet.Even still detected the sky aspiration and gone into if carry out replenishing after the multi-pass operation water inlet, then judge and taken place unusually, operation is ended or made the motor counter-rotating, remove the operations such as foreign matter in the draining valve, unloaded phenomenon takes place to prevent heater.

On the other hand, when carrying out drain operation, be lower than setting by input and can judge and sucked air, like this, by rotating speed being controlled the noise in the time of can reducing draining.

The utility model be owing to can detect the variation of motor loads such as power input to machine and torque variation in moment, so be very suitable for changing the non-equilibrium state that detects clothing by the detection torque when washing machine or clothes washer-dryer carry out dehydrating operations.

(embodiment 3)

Figure 17 is the block diagram of the control device of the motor driver among the 3rd embodiment, after this control device detects motor torque, reactive current Isin φ is controlled, thereby makes operating efficiency reach maximum.

Figure 17 has carried out a part of improvement to the block diagram shown in the Figure 13 among the 2nd embodiment, thus below only the part of having improved is described.Wherein, the electromotive power output calculation element 77 of frequency converter calculates frequency converter electromotive power output that is power input to machine from frequency converter output voltage Va and effective current Ia, described motor input signal and driving frequency signal are added on the torque current calculation element 79, obtain motor torque electric current I q according to formula 6 again.

Effective current calculation element 80 is obtained current of electric vector absolute value Im from formula 2, current of electric comparison means 81 compares torque current Iq and current of electric vector absolute value Im, and reactive current modifier 82 changes reactive current set point Isin φ according to the difference signal between Im and the Iq.Specifically, when Im increases with respect to Iq, the set point of Isin φ is reduced, when Im reduces with respect to Iq, the set point of Isin φ is increased, thereby be controlled to Im and Iq basic identical.Because make I shown in Fig. 5 and Iq become equal substantially by control Isin φ, I is coaxial with the q axle, therefore can reach the maximum operating efficiency identical with vector control.

When carrying out that current of electric vector absolute value Im and torque current Iq be controlled to essentially identical operation, want to realize that such control is the comparison difficulty during the high torque operation when starting, therefore, do not carry out such control when being preferably in starting, but after rotating speed reaches necessarily substantially, carry out Control Circulation again.In addition, the dishwasher pump motor that changes greatly compared with load torque comes, and present embodiment is more suitable in the cylinder in the compressor of air conditioner, fan electromotor etc. or the drum type washing machine etc. being rotated control.

In sum, the utility model is after detecting 3 phase frequency converter output currents, carrying out 3 phases → 2 phase inversion, carry out coordinate conversion by standard shaft and control motor reactive current or current phase, can make dc brushless motor (permanent-magnet synchronous motor) realize no transducer sine wave drive to the converter circuit output voltage.In addition, power output or the output voltage from frequency converter can detect load condition.

Because the utility model just can detect the load condition of input of frequency converter electromotive power output that is motor and motor in moment, therefore can realize the control identical with vector control, thereby can make operating efficiency reach maximum, realize the Optimal Control that adapts with load.

In addition, the utility model can also detect load variations in moment, thereby can the air suction situation of water pump be detected, and can go out dehydration the washing machine laod unbalance situation of washing tube and swing roller etc. of holding concurrently from the torque change-detection of motor.

In addition, the detection of loss of mains of motor also is easy to carry out, and can carry out abnormal alarm under the occasion of step-out or restarts after changing drive condition such as reactive current producing, and rotation is driven realize stabilisation.

In addition, in existing no transducer sine wave drive mode, the calculating of carrying out position deduction is very complicated, processor burden very big; In addition, carry out position deduction and calculate the necessary parameter of electric machine, need carry out the chronic of various tests, cost in order to obtain.In contrast, adopt words of the present utility model, owing to need not to carry out position deduction, the calculation procedure of processor can reduce, and the figure place of calculated data also can reduce, and also needs the parameter of electric machine hardly, and can automatically realize maximum operating efficiency.Therefore, can alleviate the burden of processor, can realize the control identical, thereby realize cheaply, can realize not having the motor driver of transducer sine wave drive with vector control.

Particularly, in the Electric Machine Control of clothes washer-dryer and dishwashing detergent cleaning machine and operating process control, need complicated program, in addition, also need carrier frequency is arranged to ultrasonic frequency to reduce noise, therefore, in existing no transducer sine wave drive mode, the procedure quantity of processor controls and calculated performance burden are very big, need expensive processor, and adopt words of the present utility model, just can realize and do not have the identical performance of sensor vector control by the processor of cheapness, thereby can reduce the cost of clothes washer-dryer and dishwashing detergent cleaning machine.

In addition, though above serve as main being illustrated with the SPM motor, it should be apparent that the utility model also goes for being embedded with in the core rotor ipm motor of permanent magnet.

In addition, certain by the phase place of frequency converter output voltage and output current or effective current Icos φ are controlled to, also can reach same effect.

As mentioned above, motor driver of the present utility model is transformed into direct current by rectification circuit with alternating current, by the converter circuit drive motors, detect the output current of converter circuit by current sensing means, converter circuit is carried out pulse width modulation controlled to reach the setting rotating speed, and converter circuit output voltage, current phase or reactive current be controlled to setting, by converter circuit output voltage or power output load condition is judged.Therefore, the rotation abnormal conditions of motor and torque variation are easy to detect, not only can be used for the pump motor of the dish cleaning machine shown in the embodiment, and compressor electric motor, fan electromotor and the washing machine, the dehydration in the clothes washer-dryer that the go for air conditioner Spin Control of washing tube and swing roller of holding concurrently.

Claims (6)

1. motor driver is characterized in that comprising:

AC power;

The alternating current with described AC power that links to each other with described AC power is transformed into galvanic rectification circuit:

The direct current with described rectification circuit that links to each other with described rectification circuit is transformed into the converter circuit of alternating current:

The motor that drives by described converter circuit that links to each other with described converter circuit;

Being used to of linking to each other with the negative voltage side of described converter circuit detected the current sensing means of the output current of described converter circuit; With

With the output signal of passing through described current sensing means that described current sensing means links to each other with described converter circuit described converter circuit is carried out pulse width modulation controlled, makes its rotating speed become the control device of set point thereby control described motor,

Described control device comprises the high-speed a/d converting means that links to each other with described current sensing means, 3 phases → 2 phase standard shaft converting means link to each other with described high-speed a/d converting means, the load condition judgment means of load condition being judged from the output voltage of described converter circuit or power output with described 3 mutually → 2 phase standard shaft converting means link to each other.

2, motor driver as claimed in claim 1, it is characterized in that: described control device also comprise by the reactive current comparison means with described 3 mutually → 2 the reactive current setting device and the error signal that link to each other of phase standard shaft converting means amplify calculation element, the drive condition setting device links to each other with described reactive current setting device, the V/f setting device links to each other with described drive condition setting device, described load condition judgment means and described V/f setting device with amplify calculation element with described error signal and link to each other.

3, motor driver as claimed in claim 1, it is characterized in that: described control device comprises also and the described 3 electromotive power output calculation elements that link to each other of phase standard shaft converting means mutually → 2 that described load condition judgment means links to each other with described electromotive power output calculation element.

4, as claim 2 or 3 described motor drivers, it is characterized in that: described control device also comprises speed setting device, described speed setting device links to each other with described V/f setting device with described drive condition setting device, the electricity phase angle is calculated device and is linked to each other with described speed setting device, and storage device and coordinate transformation device calculate device with described electric phase angle and link to each other.

5, motor driver as claimed in claim 2 is characterized in that: described control device also comprises the drive condition change device that links to each other with described drive condition setting device.

6, motor driver as claimed in claim 2 is characterized in that: described control device also comprises the restarting device that abends that links to each other with described load condition judgment means with described drive condition change device.

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