CN101546978A - Control method of complete-period generator of bearing-free switch reluctance motor - Google Patents

Abstract

The invention discloses a control method of a complete-period generator of a bearing-free switch reluctance motor, belonging to a control method of a bearing-free switch reluctance generator. In the method, through the judgment on suspension force directions, a corresponding suspension current computing formula which is adopted under the condition of different suspension force directions is designed as follows: confirming the plus and the minus in a concrete suspension force current formula based on the judgment on the output voltage amplitude; and setting an output voltage hysteresis controlling unit in order to reduce the output voltage ripple and avoid the control complexity caused by frequent change of the current direction of suspension windings. The invention constructs a suspension winding current control method from the angle of minimum suspension power consumption and lays a foundation for the theoretical research and the practical application of the complete-period generator of the bearing-less switch reluctance motor.

Description

The control method of complete-period generator of bearing-free switch reluctance motor

Technical field

The present invention relates to a kind of control method of complete-period generator of bearing-free switch reluctance motor, belong to the bearing-free switch magnetic-resistance generator control method.

Background technology

Traditional switched reluctance machines adopts periodically timesharing power generation mode, compares with magneto, and power density is its limitation.In order to remedy the periodically limitation of timesharing power generation mode, a kind of complete-period electrification operational mode based on the double winding bearing-free switch reluctance motor is suggested.With 12/8 bearing-free switch magnetic-resistance complete-period generator is example, Fig. 1 is A phase winding structure chart (other two phase winding does not mark), and motor adopts concentrates winding, and two cover windings are arranged on each stator salient poles, the one, by four main windings that are in series on the salient pole, main winding connects rectifying installation; The 2nd, each extremely goes up the suspending windings of independent control, and suspending windings connects asymmetrical half-bridge.As shown in Figure 2, make the magnetic field influence of unbalance of a pair of utmost point of rotor both sides produce the axial asymmetric radially magnetic pull of α by the suspending windings electric current that suspending windings α axle is led to direction as shown and vary in size, reach the purpose of regulating the rotor radial position thereby in like manner can produce the axial asymmetric radially magnetic pull of β.The suspending windings electric current can be used as the exciting current of generating, in the motor rotation process, will have induced potential to produce in the main winding.After suspending windings was finished excitation, cut-off current, main winding afterflow generating entered the afterflow power generating stage that is similar to the conventional switch reluctance generator.Therefore, the bearing-free switch reluctance motor that works under this power generation mode is called the bearing-free switch magnetic-resistance complete-period generator.

In the bearing-free switch magnetic-resistance complete-period generator, suspending windings is not only born the task of producing controllable radial power, and the function of excitation also is provided for complete-period electrification simultaneously.Therefore, the control method of suspending windings electric current is related to the performance that suspends and generate electricity, and is necessary to study a kind of method of effective control suspending windings electric current, to realize that the bearing-free switch magnetic-resistance complete-period generator suspends and the premium properties of generating.

Summary of the invention

The present invention seeks to provide a kind of control method of complete-period generator of bearing-free switch reluctance motor at the defective that prior art exists.

The present invention adopts following technical scheme for achieving the above object:

The control method of complete-period generator of bearing-free switch reluctance motor of the present invention is characterized in that comprising the steps:

A.) adopt the axial radial displacement transducer of β to detect described bearing-free switch reluctance motor and obtain the actual displacement of β direction of principal axis, adopt the axial radial displacement transducer of α to detect described bearing-free switch reluctance motor and obtain the actual displacement of α direction of principal axis, described bearing-free switch reluctance motor main winding voltage is obtained main winding virtual voltage U through rectifying installation ₀, wherein the β axle is the longitudinal axis in the rectangular coordinate system, the α axle is the transverse axis in the rectangular coordinate system, down together;

B.) given bearing-free switch reluctance motor β direction of principal axis is obtained bearing-free switch reluctance motor β direction of principal axis suspending power with reference to the difference of displacement and the actual displacement of the described β direction of principal axis of step a through a PID adjuster Given bearing-free switch reluctance motor α direction of principal axis is obtained bearing-free switch reluctance motor α direction of principal axis suspending power with reference to the difference of displacement and the actual displacement of the described α direction of principal axis of step a through the 2nd PID adjuster

With given bearing-free switch reluctance motor main winding reference voltage

With the described main winding virtual voltage of step a U ₀Difference through pi regulator adjusted current value;

C.) with the described bearing-free switch reluctance motor β of step b direction of principal axis suspending power

α direction of principal axis suspending power

Reference voltage

With main winding virtual voltage U ₀Poor, regulate current value and main winding current i _m, described bearing-free switch reluctance motor stator upper position sensor detects the position signalling θ that obtains and obtains β axle, the floating winding current of α axle suspension through the suspending windings current controller;

D.) the floating winding current of the described β axle suspension of step c is obtained the Control current that described bearing-free switch reluctance motor β axle suspension is floated winding through the floating winding inverter of β axle suspension, the floating winding current of the described α axle suspension of step c is obtained the Control current of the floating winding of described bearing-free switch reluctance motor α axle suspension through the floating winding inverter of α axle suspension.

The control method of complete-period generator of bearing-free switch reluctance motor of the present invention is by the asymmetric excitation of suspending windings of relative position produces the radial suspension force that unbalanced radially magnetic pull obtains acting on rotor to being positioned at radially.If need the radial load of positive direction, then the air gap flux density amplitude at negative direction place is more little, and it is more little that suspending windings produces the required exciting power of same radial power.This programme has been set up the different suspension electric current computing formula of employing under the different suspending power directions based on this principle.Simultaneously, in order to reduce output voltage ripple and to avoid suspending windings sense of current frequent variations and complexity in the control that brings, be provided with the output voltage ring controlling unit that stagnates.

Description of drawings

Fig. 1 is a non-bearing switch reluctance motor complete-period electrification structure A phase winding structure chart.

Fig. 2 is non-bearing switch reluctance motor complete-period electrification suspension mechanism figure.

Fig. 3 is control principle figure of the present invention.

Number in the figure meaning: 1-stator, 2-rotor, 3-bearing-free switch reluctance motor main winding, 4-bearing-free switch reluctance motor suspending windings, 5-asymmetrical half-bridge power inverter, 6-rectifying installation, 7-α axial coordinate, 8-β axial coordinate.

Embodiment

Be elaborated below in conjunction with the technical scheme of accompanying drawing to invention:

As shown in Figure 1, be non-bearing switch reluctance motor complete-period electrification structure A phase winding structure chart.

As shown in Figure 2:

1. selecting the α axle for use is that example illustrates.Set up radial suspension force expression formula (1) according to existing theory.

2. by the detection rotor radial displacement, after the adjusting of PID controller, export given suspending power F ^*Judge that whether given suspending power is greater than 0.If F ^*0, then calculate i according to formula (2) _S3, calculate i according to formula (3) _S1If F ^*＜0, then ask for i according to formula (4) _S1, calculate i according to formula (5) _S3

3. compare actual output voltage U _oWith given output voltage U _o ^*If U _oU _o ^*, in formula (3) and (5) ± get-number; If U _o＜U _o ^*, in formula (3) and (5) ± get+number.If in the suspending windings current formula (3) ± get-number the time, U _oStill greater than U _o ^*, can pass through Δ U=U _o-U _o ^*Carry out PI and regulate, make i _S3Thereby reducing to reach reduces the suspending windings current i _S1Purpose; When in suspending windings electric current (3) formula ± get+number the time, U _oStill less than U _o ^*, can regulate Δ U by the PI controller and make i _S3Increase, increase the suspending windings current i thereby reach _S1Purpose.

4. be complexity in the control of avoiding bringing owing to electric current positive and negative frequent variations among Fig. 3 and minimizing output voltage ripple, the stagnant ring of output voltage controlling unit need be set.Wherein, the stagnant ring of voltage lower limit is set to U ₁ ^*, the stagnant ring of the voltage upper limit is set to U ₂ ^*When detecting Uo＜U ₁ ^*, in formula (3), (5) ± number get+number; When detecting U ₁ ^*＜Uo＜U ₂ ^*, in formula (3), (5) ± number orientation identical with a last sense cycle; When detecting Uo〉U ₂ ^*, in formula (3), (5) ± number get-number.Simultaneously, can realize the control among similar Fig. 3 by Δ U is regulated through the PID controller.

5. the control method of β shaft current is similar to the above.

Because the suspending windings sense of current can change, therefore need to adopt the power inverter of adjustable current direction when control.

Formula table

F in the table _α---the radial load of α direction, N _mBe the number of turn, the N of main winding _bBe the suspending windings number of turn, i _m---main winding current, i _S1---α axle positive direction suspending windings electric current, i _S3---α axle negative direction suspending windings electric current, k _f(θ)---the suspending power coefficient, relevant with motor size and rotor position angle.

As shown in Figure 3, the control method of complete-period generator of bearing-free switch reluctance motor is characterized in that comprising the steps:

A.) adopt the axial radial displacement transducer of β to detect described bearing-free switch reluctance motor and obtain the actual displacement of β direction of principal axis, adopt the axial radial displacement transducer of α to detect described bearing-free switch reluctance motor and obtain the actual displacement of α direction of principal axis, described bearing-free switch reluctance motor main winding voltage is obtained main winding virtual voltage U through rectifying installation ₀, wherein the β axle is the longitudinal axis in the rectangular coordinate system, the α axle is the transverse axis in the rectangular coordinate system, down together;

B.) given bearing-free switch reluctance motor β direction of principal axis is obtained bearing-free switch reluctance motor β direction of principal axis suspending power with reference to the difference of displacement and the actual displacement of the described β direction of principal axis of step a through a PID adjuster

Given bearing-free switch reluctance motor α direction of principal axis is obtained bearing-free switch reluctance motor α direction of principal axis suspending power with reference to the difference of displacement and the actual displacement of the described α direction of principal axis of step a through the 2nd PID adjuster

With given bearing-free switch reluctance motor main winding reference voltage With the described main winding virtual voltage of step a U ₀Difference through pi regulator adjusted current value;

C.) with the described bearing-free switch reluctance motor β of step b direction of principal axis suspending power

α direction of principal axis suspending power

Reference voltage

With main winding virtual voltage U ₀Poor, regulate current value and main winding current i _m, described bearing-free switch reluctance motor stator upper position sensor detects the position signalling θ that obtains and obtains β axle, the floating winding current of α axle suspension through the suspending windings current controller;

D.) the floating winding current of the described β axle suspension of step c is obtained the Control current that described bearing-free switch reluctance motor β axle suspension is floated winding through the floating winding inverter of β axle suspension, the floating winding current of the described α axle suspension of step c is obtained the Control current of the floating winding of described bearing-free switch reluctance motor α axle suspension through the floating winding inverter of α axle suspension.

The control method of described complete-period generator of bearing-free switch reluctance motor is characterized in that asking for of the described suspending windings electric current of step c comprises the steps:

When required suspending power is timing

E.) the suspending windings electric current at adjusting negative direction place $i_{-}=\frac{N_m{i}_m}{N_b};$

F.) when the actual output voltage of described bearing-free switch reluctance motor greater than given output voltage amplitude, then regulate the positive direction place the suspending windings electric current $i_{+}=\frac{N_m{i}_m}{N_b}-\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}};$ When the actual output voltage of described bearing-free switch reluctance motor less than given output voltage amplitude, then regulate the positive direction place the suspending windings electric current $i_{+}=\frac{N_m{i}_m}{N_b}+\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}};$

When required radial suspension force when negative

G.) the suspending windings electric current at adjusting positive direction place is $i_{+}=\frac{N_m{i}_m}{N_b};$

H.) when the actual output voltage of described bearing-free switch reluctance motor greater than given output voltage amplitude, then regulate the negative direction place the suspending windings electric current $i_{-}=\frac{N_m{i}_m}{N_b}-\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}};$ When the actual output voltage of described bearing-free switch reluctance motor less than given output voltage amplitude, then regulate the negative direction place the suspending windings electric current $i_{-}=\frac{N_m{i}_m}{N_b}+\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}},$ Wherein F is suspending power, N _mBe the number of turn, the N of main winding _bBe the suspending windings number of turn, i _mBe main winding current, k _f(θ) be the suspending power coefficient.

The control method of described complete-period generator of bearing-free switch reluctance motor is characterized in that also comprising the voltage hysteresis control method thereof, and concrete steps are as follows:

1.) stagnate ring lower limit and actual output voltage during less than given output voltage amplitude less than voltage when the actual output voltage of bearing-free switch reluctance motor, the suspending windings electric current at positive direction place is $i_{+}=\frac{N_m{i}_m}{N_b}+\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}},$ The suspending windings electric current at negative direction place $i_{-}=\frac{N_m{i}_m}{N_b};$

2.) stagnate the ring upper limit and actual output voltage during greater than given output voltage amplitude greater than voltage when the actual output voltage of bearing-free switch reluctance motor, the suspending windings electric current at positive direction place is $i_{+}=\frac{N_m{i}_m}{N_b},$ The negative direction place the suspending windings electric current $i_{-}=\frac{N_m{i}_m}{N_b}-\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}};$

3.) when the actual output voltage of bearing-free switch reluctance motor was in the stagnant ring of voltage centre, the suspending windings electric current was identical with last one-period.

Claims (3)

1, a kind of control method of complete-period generator of bearing-free switch reluctance motor is characterized in that comprising the steps:

A.) adopt the axial radial displacement transducer of β to detect described bearing-free switch reluctance motor and obtain the actual displacement of β direction of principal axis, adopt the axial radial displacement transducer of α to detect described bearing-free switch reluctance motor and obtain the actual displacement of α direction of principal axis, described bearing-free switch reluctance motor main winding voltage is obtained main winding virtual voltage U through rectifying installation ₀, wherein the β axle is the longitudinal axis in the rectangular coordinate system, the α axle is the transverse axis in the rectangular coordinate system, down together;

B.) given bearing-free switch reluctance motor β direction of principal axis is obtained bearing-free switch reluctance motor β direction of principal axis suspending power with reference to the difference of displacement and the actual displacement of the described β direction of principal axis of step a through a PID adjuster

Given bearing-free switch reluctance motor α direction of principal axis is obtained bearing-free switch reluctance motor α direction of principal axis suspending power with reference to the difference of displacement and the actual displacement of the described α direction of principal axis of step a through the 2nd PID adjuster

With given bearing-free switch reluctance motor main winding reference voltage With the described main winding virtual voltage of step a U ₀Difference through pi regulator adjusted current value;

C.) with the described bearing-free switch reluctance motor β of step b direction of principal axis suspending power

α direction of principal axis suspending power

Reference voltage

With main winding virtual voltage U ₀Poor, regulate current value and main winding current i _m, described bearing-free switch reluctance motor stator upper position sensor detects the position signalling θ that obtains and obtains β axle, the floating winding current of α axle suspension through the suspending windings current controller;

D.) the floating winding current of the described β axle suspension of step c is obtained the Control current that described bearing-free switch reluctance motor β axle suspension is floated winding through the floating winding inverter of β axle suspension, the floating winding current of the described α axle suspension of step c is obtained the Control current of the floating winding of described bearing-free switch reluctance motor α axle suspension through the floating winding inverter of α axle suspension.

2, the control method of complete-period generator of bearing-free switch reluctance motor according to claim 1 is characterized in that asking for of the described suspending windings electric current of step c comprises the steps:

When required suspending power is timing

E.) the suspending windings electric current at adjusting negative direction place $i_{-}=\frac{N_m{i}_m}{N_b};$

F.) when the actual output voltage of described bearing-free switch reluctance motor greater than given output voltage amplitude, then regulate the positive direction place the suspending windings electric current $i_{+}=\frac{N_m{i}_m}{N_b}-\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}};$ When the actual output voltage of described bearing-free switch reluctance motor less than given output voltage amplitude, then regulate the positive direction place the suspending windings electric current $i_{+}=\frac{N_m{i}_m}{N_b}+\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}};$

When required radial suspension force when negative

G.) the suspending windings electric current at adjusting positive direction place is $i_{+}=\frac{N_m{i}_m}{N_b};$

H.) when the actual output voltage of described bearing-free switch reluctance motor greater than given output voltage amplitude, then regulate the negative direction place the suspending windings electric current $i_{-}=\frac{N_m{i}_m}{N_b}-\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}};$ When the actual output voltage of described bearing-free switch reluctance motor less than given output voltage amplitude, then regulate the negative direction place the suspending windings electric current $i_{-}=\frac{N_m{i}_m}{N_b}+\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}},$ Wherein F is suspending power, N _mBe the number of turn, the N of main winding _bBe the suspending windings number of turn, i _mBe main winding current, k _f(θ) be the suspending power coefficient.

3, the control method of complete-period generator of bearing-free switch reluctance motor according to claim 1 and 2 is characterized in that also comprising the voltage hysteresis control method thereof, and concrete steps are as follows:

1.) actual output voltage when bearing-free switch reluctance motor stagnates ring down in limited time less than voltage, by output voltage and given voltage pressure reduction PI are regulated, makes the suspending windings electric current at negative direction place $i_{-}=\frac{N_m{i}_m}{N_b}$ Increase, thereby make the suspending windings electric current at positive direction place $i_{+}=\frac{N_m{i}_m}{N_b}+\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}}$ Increase;

2.) actual output voltage when bearing-free switch reluctance motor stagnates ring upward in limited time greater than voltage, by output voltage and given voltage pressure reduction PI are regulated, makes the suspending windings electric current at positive direction place be $i_{+}=\frac{N_m{i}_m}{N_b}$ Reduce, thus make the negative direction place the suspending windings electric current $i_{-}=\frac{N_m{i}_m}{N_b}-\sqrt{\frac{F}{N_b{k}_f\left(\mathrm{\θ}\right)}}$ Reduce;

3.) when the actual output voltage of bearing-free switch reluctance motor was in the stagnant ring of voltage centre, the suspending windings electric current was identical with last one-period.

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