CN103166502B - Space phase modulation annular Traveling Ultrasonic Motor and control method thereof - Google Patents

Abstract

A kind of space phase modulation annular Traveling Ultrasonic Motor and control method, this motor is divided into A district piezoelectric ceramic and B district piezoelectric ceramic, the width of each polarization subregion of piezoelectric ceramic is that four/a line wave-wave is long, it is the half of traditional Traveling Ultrasonic Motor, polarised direction is pressed clockwise successively " ++--" arrangement, it is long that A district and piezoelectric ceramic space, B district differ four/a line wave-wave.A district and B district piezoelectric ceramic respectively apply two power supplys, totally four power supplys.Two power supplys in same district have identical time phase, different voltage magnitudes; The power supply of same district does not differ pi/2 time phase; Voltage magnitude on the piezoelectric ceramic polarization subregion that same district two/a line apart wave-wave is long is identical.This pattern annular traveling wave supersonic motor has repertoire and the advantage of traditional travelling wave motor, and can by simple voltage magnitude regulating measure, and implementation space phase shifting control, replaces traditional time phase shifting control.

Description

Space phase modulation annular Traveling Ultrasonic Motor and control method thereof

Technical field

The present invention relates to supersonic motor manufacture and control field, particularly relate to a kind of annular traveling wave supersonic motor and control method thereof.

Background technology

Annular traveling wave supersonic motor uses many a kind of supersonic motors at present, and the essence of its speeds control is the elliptical orbit of the wave amplitude of change row ripple, speed and particle, and three corresponding base control amounts are voltage magnitude, frequency and phase difference.Conventional control program is combined voltage, frequency, phase place three kinds of control modes, suitable way is, utilizing voltage and frequency to realize on the basis of motor body control, utilize phase place to realize servo and export control, therefore phase-difference control is one of important core.

The phase-difference control scheme generally used at present is realized by the controllable power supply of two-phase relation time phase, the i.e. each autoexcitation of supersonic motor two-phase independently standing wave, these two standing waves are fixing in locus and mutual deviation four/a line wave-wave is long, but time phase is adjustable, time phase, size depended on the time phase of respective power supply.When power supply actuation duration phase place mutual deviation pi/2, it synthesizes a pure row ripple.And when the power supply actuation duration, phase place mutual deviation value departed from pi/2 gradually, inside synthetic waveform, comprise traveling and standing wave, and bias is larger, standing wave is larger, thus changes motor speed.In order to realize the continuous control of motor speed, continuously adjustable time phase must be obtained, the employing Direct Digital that people are many, but control non-linear, and circuit is complicated.

Summary of the invention

The object of the invention is to solve the problem, provide one to utilize space phase to regulate the phase-adjusted annular traveling wave supersonic motor of takeover time and control method.

The present invention is by the following technical solutions:

A kind of space phase modulation annular Traveling Ultrasonic Motor, comprise piezoelectric ceramic, it is characterized in that, described piezoelectric ceramic comprises A district piezoelectric ceramic and B district piezoelectric ceramic, it is long that A district piezoelectric ceramic and piezoelectric ceramic space, B district differ four/a line wave-wave, the piezoelectric patches polarization subregion that A district piezoelectric ceramic and B district piezoelectric ceramic adopt four/a line wave-wave long, and along clockwise direction, the polarised direction of the piezoelectric ceramic polarization subregion in each district is all arranged in order by " ++--", described piezoelectric ceramic adopts power supply one, power supply two, power supply three, power supply four encourages, power supply one and power supply two in the direction of the clock interval action in each polarization subregion of A district piezoelectric ceramic, power supply three and power supply four in the direction of the clock interval action in each polarization subregion of B district piezoelectric ceramic, power supply one and power supply two have same time phase place, power supply three and power supply four have same time phase place, the time phase of power supply three and power supply four differs pi/2 with power supply one and power supply two, power supply one and power supply four have identical voltage magnitude, power supply two and power supply three have identical voltage magnitude.

Further, setting power supply one is a with the identical voltage magnitude that power supply four has, and the identical voltage magnitude that power supply two and power supply three have is b, and voltage magnitude a and b meets a=|b|, and the amplitude of implementation space phase modulation annular Traveling Ultrasonic Motor controls.

Further, setting power supply one is a with the identical voltage magnitude that power supply four has, and the identical voltage magnitude that power supply two and power supply three have is b, and voltage magnitude a and b meets voltage magnitude a presses do with voltage magnitude b and change, the spatial Phase-shifting Method of implementation space phase modulation annular Traveling Ultrasonic Motor controls.

Further, setting power supply one is a with the identical voltage magnitude that power supply four has, and the identical voltage magnitude that power supply two and power supply three have is b, changes the symbol of voltage magnitude b, and voltage magnitude a is just always, the rotating of implementation space phase modulation annular Traveling Ultrasonic Motor controls.

Beneficial effect of the present invention:

1, space phase modulation annular Traveling Ultrasonic Motor has this new base control amount of space phase, and this is not available for conventional ultrasonic wave motor;

2, the spatial Phase-shifting Method of space phase modulation annular Traveling Ultrasonic Motor controls to have similar effect with the time phase shifting control of traditional endless travelling wave motor, but it is realized by the change of supply voltage amplitude, and historical facts or anecdotes is now comparatively simple and convenient.

Accompanying drawing explanation

Accompanying drawing 1 is electric machine structure schematic diagram of the present invention.

Accompanying drawing 2 is piezoelectric ceramic of the present invention polarization partition scheme and power supply connection scheme schematic diagram.

Embodiment

Below in conjunction with accompanying drawing, the present invention is described further.

As shown in Figure 1, this motor comprises end cap 1, bearing 1, bearing 23, rotating shaft 4, rotor 5, stator 6, base 7, piezoelectric ceramic.Except the polarization partitioned mode of piezoelectric ceramic, other structure of motor, material and assembling scheme and conventional ultrasonic wave motor completely the same.The piezoelectric ceramic of motor is divided into A district piezoelectric ceramic 8 and B district piezoelectric ceramic 9.As shown in Figure 2, during machine operation, stator circumference is distributed with the spatial row ripple of nine wavelength, count space phase 2 π as each row wave-wave is long, whole circumference can count space phase 18 π.In the direction of the clock, the original position of definition A district piezoelectric ceramic 8 is original position, then 8 π places are the end position of A district piezoelectric ceramic 8, and 9.5 π places are the original position of B district piezoelectric ceramic 9, and 17.5 π places are the end position of B district piezoelectric ceramic 9.A district piezoelectric ceramic 8 and piezoelectric ceramic 9 inside, B district have employed the polarization partition scheme of segmentation respectively, and the space phase length of each polarization subregion is all pi/2s, and also namely four/a line wave-wave is long, is the half of traditional Traveling Ultrasonic Motor.The polarization subregion of A district piezoelectric ceramic 8 and piezoelectric ceramic 9 inside, B district all polarizes by " ++--" direction along clockwise direction."+" represents forward polarization, and "-" represents reverse polarization.

Space phase modulation annular Traveling Ultrasonic Motor must coordinate new power source design ability implementation space phase shifting control.New power source design have employed four power supplys: power supply 1, power supply 2 11, power supply 3 12, power supply 4 13.A district piezoelectric ceramic 8 in the direction of the clock, is divided into 16 piezoelectric ceramic polarization subregions, wherein in A district first, three, five, seven, nine, 11,13,15 amount to eight piezoelectric ceramic polarization subregions is connected with power supply 1, and second, four, six, eight, ten, 12,14,16 amount to eight piezoelectric ceramic polarization subregions is connected with power supply 2 11; B district piezoelectric ceramic 9 in the direction of the clock, is divided into 16 piezoelectric ceramic polarization subregions, wherein in B district first, three, five, seven, nine, 11,13,15 amount to eight piezoelectric ceramic polarization subregions is connected with power supply 3 12, and second, four, six, eight, ten, 12,14,16 amount to eight piezoelectric ceramic polarization subregions is connected with power supply 4 13.Power supply 1 and power supply 2 11 have identical time phase; Power supply 3 12 and power supply 4 13 have identical time phase, and on time phase, differ pi/2 with power supply 1 and power supply 2 11.Power supply 1 and power supply 4 13 have identical voltage magnitude, and power supply 2 11 and power supply 3 12 have identical voltage magnitude, and two voltage magnitudes are adjustable.

Power supply expression formula is described as that power supply 1 is acos ω t, power supply 2 11 is bcos ω t, power supply 3 12 is bsin ω t, power supply 4 13 is asin ω t; A is the voltage magnitude of power supply 1 and power supply 4 13, and b is the voltage magnitude of power supply 2 11 and power supply 3 12, and voltage magnitude a and b is per unit value.

Four power supplys excite four standing waves on stator, and two standing wave expression formulas that wherein A district power supply excites are

w ₁=arsin(nx+π/4)cosωtw ₂=brsin(nx-π/4)cosωt

Two standing wave expression formulas that B district power supply excites are

w ₃=brcos(nx+π/4)sinωtw ₄=arcos(nx-π/4)sinωt

Excite two standing waves of same piezoelectric regions synthesize a new standing wave, and its expression formula is

$w_A=w_1+w_2=r\sqrt{a^2+b^2}\sin (\mathrm{nx}+\mathrm{\θ})\cos \mathrm{\ωt}$

$w_B=w_3+w_4=r\sqrt{a^2+b^2}\cos (\mathrm{nx}-\mathrm{\θ})\sin \mathrm{\ωt}$

The expression formula of the complex wave that final stator synthesizes is:

$w=w_A+w_B=r\sqrt{a^2+b^2}\sin (\mathrm{nx}+\mathrm{\θ})\cos \mathrm{\ωt}+r\sqrt{a^2+b^2}\cos (\mathrm{nx}-\mathrm{\θ})\sin \mathrm{\ωt}$

Wherein ar, br are standing wave transverse vibration amplitude, and r is the coefficient of standing wave amplitude relative to voltage magnitude, and x is locus angle, and ω is angle of throw frequency, and n=l/ λ is the wave number along stator circumference, and l is stator girth, and λ is elasticity wavelength, and t is the time.In specification, same-sign represents identical implication.The expression formula of composite wave has identical expression formula form with conventional ultrasonic wave motor time phase shifting control, and it is equivalent to conventional ultrasonic wave motor time phase-shift control angle and is $2\mathrm{\θ}=2\arctan \frac{a-b}{a+b}$ Phase shifting control, correspondingly, definition space phase modulation annular travelling wave motor spatial Phase-shifting Method pilot angle be $\mathrm{\β}=2\mathrm{\θ}=2\arctan \frac{a-b}{a+b},$ Then spatial Phase-shifting Method angle is $\mathrm{\β}-\frac{\mathrm{\π}}{2}=2\mathrm{\θ}-\frac{\mathrm{\π}}{2}=-2\arctan \frac{b}{a}.$ Change a, b and can change spatial Phase-shifting Method pilot angle and spatial Phase-shifting Method angle, also can change the amplitude of complex wave simultaneously

In order to the convenience controlled, with the voltage magnitude b of power supply 2 11 and power supply 3 12 for controlled quentity controlled variable, the voltage magnitude a of power supply 1 and power supply 4 13 is for associating controlled quentity controlled variable:

1. amplitude controls

When association controlled quentity controlled variable voltage magnitude a is with controlled quentity controlled variable voltage magnitude | b| does identical change, i.e. a=|b|, can the amplitude of implementation space phase modulation annular Traveling Ultrasonic Motor control.

2. spatial Phase-shifting Method controls

When association controlled quentity controlled variable voltage magnitude a presses with controlled quentity controlled variable voltage magnitude b do change time, and can the spatial Phase-shifting Method of implementation space phase modulation annular Traveling Ultrasonic Motor control, time speed maximum.

3. rotating controls

Change the symbol of controlled quentity controlled variable voltage magnitude b, and associate controlled quentity controlled variable voltage magnitude a and be just always, can the rotating of implementation space phase modulation annular Traveling Ultrasonic Motor control.

Claims (1)

1. a control method for space phase modulation annular Traveling Ultrasonic Motor, is characterized in that:

Described space phase modulation annular Traveling Ultrasonic Motor comprises piezoelectric ceramic, described piezoelectric ceramic comprises A district piezoelectric ceramic and B district piezoelectric ceramic, it is long that A district piezoelectric ceramic and piezoelectric ceramic space, B district differ four/a line wave-wave, the piezoelectric patches polarization subregion that A district piezoelectric ceramic and B district piezoelectric ceramic adopt four/a line wave-wave long, and along clockwise direction, the polarised direction of the piezoelectric ceramic polarization subregion in each district is all arranged in order by " ++--", "+" represents forward polarization, and "-" represents reverse polarization, described piezoelectric ceramic adopts power supply one, power supply two, power supply three, power supply four encourages, power supply one and power supply two in the direction of the clock interval action in each polarization subregion of A district piezoelectric ceramic, power supply three and power supply four in the direction of the clock interval action in each polarization subregion of B district piezoelectric ceramic, power supply one and power supply two have same time phase place, power supply three and power supply four have same time phase place, the time phase of power supply three and power supply four differs pi/2 with power supply one and power supply two, power supply one and power supply four have identical voltage magnitude, power supply two and power supply three have identical voltage magnitude,

Setting power supply one is a with the identical voltage magnitude that power supply four has, and the identical voltage magnitude that power supply two and power supply three have is b, and voltage magnitude a and b meets a=|b|, and the amplitude of implementation space phase modulation annular Traveling Ultrasonic Motor controls;

Setting power supply one is a with the identical voltage magnitude that power supply four has, and the identical voltage magnitude that power supply two and power supply three have is b, and voltage magnitude a and b meets voltage magnitude a presses do with voltage magnitude b and change, the spatial Phase-shifting Method of implementation space phase modulation annular Traveling Ultrasonic Motor controls;

Setting power supply one is a with the identical voltage magnitude that power supply four has, the identical voltage magnitude that power supply two and power supply three have is b, change the symbol of voltage magnitude b, and voltage magnitude a is just always, the rotating of implementation space phase modulation annular Traveling Ultrasonic Motor controls.