CN110190797B

CN110190797B - Vibration control system and washing machine

Info

Publication number: CN110190797B
Application number: CN201811024422.7A
Authority: CN
Inventors: 马饲野祐贵; 岩路善尚; 法月邦彦
Original assignee: Hitachi Global Life Solutions Inc
Current assignee: Hitachi Global Life Solutions Inc
Priority date: 2018-02-23
Filing date: 2018-09-04
Publication date: 2022-08-02
Anticipated expiration: 2038-09-04
Also published as: TWI675950B; JP2019143780A; JP6975659B2; CN110190797A; TW201937034A

Abstract

The invention provides a low-cost vibration control system and a washing machine which properly control the vibration of an object. It is characterized by comprising: a linear actuator (10) which includes a mover and a stator, and which is connected to a target (G) that can vibrate; a current detection unit (50) that detects the current value (i) of the current flowing in the linear actuator (10); an acceleration/position estimation unit (60) that estimates the relative acceleration (am) and/or the relative position (xm) of the mover and the stator of the linear actuator (10) on the basis of the current value (i) detected by the current detection unit (50); and a thrust adjustment unit (90) that adjusts the thrust of the linear actuator (10) on the basis of the relative acceleration (am) and/or the relative position (xm) estimated by the acceleration/position estimation unit (60).

Description

Vibration control system and washing machine

Technical Field

The present invention relates to a vibration control system for controlling vibration of an object and a technique of a washing machine.

Background

For example, patent document 1 discloses a vibration damping device of a washing machine, "including: a linear motor and an elastic body disposed between the washing tub and the casing; a current detection unit for detecting a current flowing through a winding of the linear motor and outputting a current signal; a relative position calculating unit for detecting a relative position of a mover of the linear motor and calculating a moving distance of the mover; a relative acceleration sensor detecting a relative acceleration of the washing tub or the casing and outputting a relative acceleration signal; an excitation force calculation unit that calculates an excitation force signal based on the movement distance, the relative acceleration signal, and an elastic constant of the elastic body; a torque control unit that outputs a command q-axis current value based on a difference between the excitation force signal and a target vibration value; and a power supply control unit for controlling power supply to the winding based on the current signal and the command q-axis current value (refer to the abstract of the specification).

Documents of the prior art

Patent literature

Patent document 1: japanese patent laid-open publication No. 2011-182934

Disclosure of Invention

Technical problem to be solved by the invention

However, since the vibration damping device of patent document 1 is provided with a relative acceleration sensor for detecting vibration of the washing machine, the cost increases.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a low-cost vibration control system and a washing machine that appropriately control vibration of an object.

Means for solving the problems

In order to solve the above problems, the present invention includes: a driving unit including a mover and a stator, and connected to an object capable of vibrating; a current detection unit that detects a current value of the current flowing in the drive unit; an estimation unit that estimates a relative acceleration and/or a relative position of the mover and the stator of the drive unit based on the current value detected by the current detection unit; and a thrust adjusting unit that adjusts the thrust of the driving unit based on the relative acceleration and/or the relative position estimated by the estimating unit.

Other solutions are described in the embodiments below.

Effects of the invention

According to the present invention, it is possible to provide a low-cost vibration control system and a washing machine that appropriately control vibration of an object.

Drawings

Fig. 1 is a diagram showing a configuration example of a vibration control system Z used in the first embodiment.

Fig. 2 is a vertical sectional perspective view of the linear actuator 10 provided in the vibration control device 100.

Fig. 3 is an end view taken along line a-a of fig. 2.

Fig. 4 is a diagram (example 1) showing a method of fixing the linear actuator 10.

Fig. 5 is a diagram (example 2) showing a method of fixing the linear actuator 10.

Fig. 6 is a diagram showing the configuration of the rectifier circuit Re and the inverter unit 40 provided in the vibration control apparatus 100.

Fig. 7 is a diagram showing connection of 3 linear actuators 10b to 10d (10) to a rectifier circuit Re and an inverter unit 40.

Fig. 8 is a diagram showing a specific configuration of the current command generating unit 70 and the voltage command generating unit 80 used in the first embodiment.

Fig. 9 is a diagram showing a specific configuration example of the acceleration estimation unit 610 in the acceleration/position estimation unit 60.

Fig. 10 is a diagram showing a specific configuration example of the position estimation unit 620 in the acceleration/position estimation unit 60.

Fig. 11 is a diagram showing the configuration of a vibration control system Za used in the second embodiment.

Fig. 12 is a diagram showing the configuration of a current command generating unit 70a used in the second embodiment.

Fig. 13 shows a variation of the gains m and k.

Fig. 14 is a diagram showing the result of the control according to the example shown in fig. 13.

Fig. 15 shows another example of changing the gain m or k.

Fig. 16 is a diagram showing the result of the control according to the example shown in fig. 15.

Fig. 17 is a diagram showing a configuration example of the vibration control system Zb used in the third embodiment.

Fig. 18 is a diagram showing a configuration example of the current command generating unit 70b used in the third embodiment.

Fig. 19 is a diagram showing a relationship between the vibration frequency f and the absolute value of the vibration amplitude of the object G when the gain k is changed.

Fig. 20 is a diagram showing a configuration example of a vibration control system Zc used in the fourth embodiment.

Fig. 21 is a perspective view of washing machine W provided with vibration control device 100.

Fig. 22 is a vertical cross-sectional view of washing machine W provided with vibration control device 100.

Fig. 23 is a diagram showing the configuration of the rectifier circuit Re and the inverter unit 40 used in the fourth embodiment.

Detailed Description

Next, a mode for carrying out the present invention (referred to as "embodiment") will be described in detail with reference to the drawings as appropriate. In the drawings, the same components are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

First embodiment

(vibration control system Z)

The vibration control system Z is for damping vibration of the object G, and includes a rectifier circuit (rectifier) Re and a vibration control device 100.

The rectifier circuit Re converts an ac voltage input from the ac power supply E into a dc voltage and outputs the dc voltage. The rectifier circuit Re will be described later.

The vibration control device 100 uses the dc voltage input from the rectifier circuit Re as a drive source to damp vibration of the object G. The vibration damping in the present embodiment means that the vibration frequency of the object G vibrating at the resonance frequency is shifted.

(vibration control device 100)

Next, the configuration of the vibration control device 100 that controls the linear actuator (driving unit, second driving unit) 10 will be described.

The vibration control device 100 includes a linear actuator 10, an inverter section (power conversion section) 40, a current detection section 50, an acceleration/position estimation section (estimation section) 60, and a thrust adjustment section 90. The thrust force adjusting unit 90 includes a current command generating unit 70 and a voltage command generating unit 80.

The linear actuator 10 is connected to (e.g., in contact with) the object G. The actuator 10 is linearly moved by the input ac voltage, and transmits the motion to the object G. As will be described later with respect to the linear actuator 10.

The inverter unit 40 is an inverter that converts a dc voltage input from the rectifier circuit Re into an ac voltage based on the voltage command value V from the voltage command generating unit 80. The inverter unit 40 is assumed to be controlled by PWM (Pulse Width Modulation), but is not limited thereto. The inverter section 40 will be described later.

The double-headed arrow shown in the object G indicates vibration of the object G. The "+" and "-" in the rectifier circuit Re indicate the polarities of the voltages output from the rectifier circuit Re.

The current detection unit 50 is provided downstream of the inverter unit 40, and detects a current flowing in the inverter unit 40, that is, a current value i of a current flowing in the linear actuator 10.

The acceleration/position estimation unit 60 estimates the relative acceleration am and the relative position xm of the linear actuator 10 based on the current value i detected by the current detection unit 50. The acceleration/position estimating section 60, the relative acceleration am, and the relative position xm will be described later.

The current command generation unit 70 generates a current command value i on the basis of the relative acceleration am and the relative position xm estimated by the acceleration/position estimation unit 60. The current command generating section 70 will be described later.

The voltage command generating unit 80 generates a voltage command value V based on the current command value i generated by the current command generating unit 70 and the current value i detected by the current detecting unit 50. The generated voltage command value V is input to the inverter unit 40. The voltage command generating portion 80 will be described later.

(Linear actuator 10)

Next, the linear actuator 10 will be described with reference to fig. 2 to 5. The linear actuator 10 shown in fig. 2 to 5 is merely an example, and the structure shown in fig. 2 to 5 may not be provided.

Here, the xyz axis is defined as shown in fig. 2. Also, fig. 2 illustrates only half of the linear actuator 10 in the x direction, and the structure of the linear actuator 10 is symmetrical about the yx plane.

The linear actuator 10 includes a stator 11 as an armature, and a plate-shaped mover 12 extending in the z direction. The linear actuator 10 is a motor that linearly changes the relative position of the stator 11 and the mover 12 in the z direction using magnetic attraction and repulsion (i.e., thrust) in the z-axis direction between the stator 11 and the mover 12. As described later, in the linear actuator 10, either one of the mover 12 and the stator 11 is connected to the object G.

The stator 11 has a core 11a formed by laminating electromagnetic steel plates, and is provided with a plurality of windings 11b wound around the magnetic pole teeth M of the core 11 a.

Fig. 3 is an end view taken along line a-a of fig. 2. In which fig. 3 does not represent half of the linear actuator 10 in the x-direction (refer to fig. 2), but illustrates the entire linear actuator 10.

As shown in fig. 3, the core 11a of the stator 11 includes an annular portion N and magnetic pole teeth M (M1, M2).

The annular portion N is annular (rectangular frame-shaped) in a longitudinal sectional view, and the annular portion N forms a magnetic circuit. The pair of magnetic pole teeth M1, M2 extend inward in the y direction from the annular portion N and face each other. The distance between the magnetic pole teeth M1 and M2 is slightly longer than the thickness of the plate-shaped mover 12. The windings 11b (11b1, 11b2) are wound around the magnetic pole teeth M1, M2, respectively. By supplying current to this winding 11b, the stator 11 functions as an electromagnet.

In the example shown in fig. 2, 2 pairs of magnetic pole teeth M are provided in the z direction (the moving direction of the mover 12). The windings 11b wound around the 2 pairs of magnetic pole teeth M are configured as one winding 11b, and both ends thereof are connected to the output side of the inverter unit 40 (see fig. 1).

The mover 12 shown in fig. 3 penetrates the annular core 11a and extends in the z direction. As shown in fig. 2, the mover 12 includes a plurality of metal plates 12a extending in the z direction and

permanent magnets

121b, 122b, 123b provided on the metal plates 12a at predetermined intervals in the z direction. Here, the plurality of permanent magnets may be attached to the metal plate 12a, or the plurality of permanent magnets may be embedded in the metal plate 12 a.

The

permanent magnets

121b, 122b, 123b shown in fig. 2 are magnetized in the y direction. In more detail, permanent magnets (for example,

permanent magnets

121b, 123b) magnetized in the positive direction of the y direction and permanent magnets (for example, permanent magnet 122b) magnetized in the negative direction of the y direction are alternately arranged in the z direction. Accordingly, the z-direction thrust is generated to the mover 12 by the attractive and repulsive forces between the mover 12 and the stator 11 functioning as an electromagnet. Here, the "thrust" refers to a force that changes the relative position of the mover 12 and the stator 11.

(method of fixing the Linear actuator 10)

In the example shown in fig. 4, one end of the mover 12 of the linear actuator 10 is connected to the object G, and the other end is fixed to a fixing jig (jig) J via a spring (elastic body) 20.

Here, the spring (elastic body) 20 is a spring that applies an elastic force to the mover 12, and is provided between the mover 12 and the fixing jig J. The fixing jig J is provided on the ground or the like, for example. As shown in fig. 4, the mover 12 penetrates the stator 11.

In the example of fig. 5, one end of the stator 11c of the linear actuator 10a may be connected to the object G, and the other end may be fixed to the fixing jig J via a spring (elastic body) 20 a. One end of the mover 12a is connected to the fixing jig J, and the other end is not connected to anything.

In the example of fig. 4 and 5, one end of the

stators

11 and 11c is connected to the object G, but one end of the

stators

11 and 11c may be fixed to the object G by a screw or the like.

Although not shown, a spring (elastic body) and the linear actuator 10 may be fixed to the fixing jig J and the object G in parallel.

As shown in fig. 4 and 5, one of the stator 11 and the mover 12 may be connected to the object G, and the relative position of the stator 11 and the mover 12 may be changed by a magnetic attraction force and a repulsive force.

(rectifier circuit Re, inverter 40)

Fig. 6 is a diagram showing the configuration of the rectifier circuit Re and the inverter unit 40 provided in the vibration control apparatus 100. Among them, the rectifier circuit Re and the inverter section 40 are conventional technologies.

Here, fig. 6 shows a configuration in the case of controlling 2 linear actuators 10 using a three-phase full-bridge inverter. The first linear actuator 10 is referred to as a linear actuator 10b, and the second linear actuator 10 is referred to as a linear actuator 10 c.

In the case of controlling only 1 linear actuator 10, the inverter unit 40 may use a single-phase full bridge circuit.

The inverter unit 40 shown in fig. 1 converts the direct-current voltage applied by the rectifier circuit Re into a single-phase alternating-current voltage based on the voltage command value V from the voltage command generation unit 80. Then, the inverter section 40 applies the single-phase alternating-current voltage to the winding 11b (refer to fig. 2 and 3) of the linear actuator 10. That is, the inverter unit 40 has a function of driving the linear actuator 10 based on the voltage command value V.

(rectifier circuit Re)

The rectifier circuit Re is a well-known voltage doubler rectifier circuit that converts an ac voltage applied from the ac power supply E into a dc voltage. The rectifier circuit Re includes a diode bridge circuit Re1 in which diodes D1 to D4 are connected in a bridge manner, and 2 smoothing capacitors Ch connected in series.

Then, the voltage (dc voltage including a pulsating current) applied from the diode bridge circuit Re1 is smoothed by the smoothing capacitor Ch, and a dc voltage E equivalent to approximately 2 times the voltage of the ac power supply E is generated _DC 。

The rectifier circuit Re is connected to the inverter unit 40 via the positive-side wiring 201a and the negative-side wiring 201 b. The "+" and "-" in fig. 6 indicate the polarities of the voltages output from the rectifier circuit Re.

(inverter 40)

The inverter unit 40 converts the dc voltage into a single-phase ac voltage, and applies the single-phase ac voltage to the windings 11b (see fig. 2 and 3) of the

linear actuators

10b and 10 c.

As the switching elements S1 to S6 of the inverter unit, for example, IGBTs (Insulated Gate Bipolar transistors) are used. Flywheel diodes D are connected in parallel in reverse directions to the switching elements S1 to S6, respectively. When IGBTs are used as the switching elements S1 to S6 and the inverter unit 40 generates an ac voltage by PWM control, the gate of the IGBT is connected to a pulse generator unit, not shown. The pulse generator generates a pulse having a duty ratio corresponding to the value of the voltage command value V output from the voltage command generator 80 shown in fig. 1.

The inverter unit 40 is turned ON (i.e., operated) when the vibration frequency of the linear actuator 10 (i.e., the object G) is close to the resonance frequency, and is turned OFF (i.e., not operated) otherwise.

The connection point of the switching elements S1 and S2 is connected to the winding 11b of the linear actuator 10b via the wiring 201 c. That is, one linear actuator 10b is connected to the arm corresponding to one phase of the three-phase inverter unit 40.

The connection point of the switching elements S5 and S6 is connected to the winding 11b of the linear actuator 10c via a wiring 201 e. That is, the other linear actuator 10c is connected to the other arm corresponding to one phase of the three-phase inverter unit 40.

That is, fig. 6 shows an example in which 2 linear actuators 10 are in contact with the object G.

The

linear actuators

10b and 10c are preferably connected to the inverter unit 40 so as to vibrate in the same direction.

The connection point between the switching elements S3 and S4 is connected to the winding 11b of the linear actuator 10b via the wiring 201d, and also connected to the winding 11b of the linear actuator 10 c. That is, the remaining arms of three-phase inverter unit 40 are connected to linear actuator 10b and linear actuator 10 c.

As described above, the inverter units 40 are not provided corresponding to the

linear actuators

10b and 10c, respectively, but the

linear actuators

10b and 10c are commonly connected to one inverter unit 40. In this way, the cost of the inverter unit 40 can be reduced. Then, by controlling ON/OFF of the switching elements S1 to S6 based ON PWM control, a single-phase ac voltage can be applied to the windings 11b of the

linear actuators

10b and 10 c.

The current detection unit 50 detects a current value i of the current supplied to the

linear actuators

10b and 10c, which are the inverter unit 40. The current detection unit 50 is provided on a wiring 201f located downstream of the inverter unit 40. That is, the current value i of the current flowing through the winding 11b of the

linear actuators

10b and 10c is detected by the current detection unit 50. However, at the time when the switching elements S2 and S3 are turned ON, the current value i detected by the current detection unit 50 needs to be inverted.

The wiring 201f is a wiring for connecting the emitters of the switching elements S2, S4, and S6 to the wiring 201 b.

Here, when the object G (see fig. 1) vibrates, the stator 11 (see fig. 2) and the mover 12 (see fig. 2) of the linear actuator 10 relatively move. An induced voltage is then generated in the winding 11 b. The induced voltage causes a change in the current flowing through the inverter unit 40 and the wiring 201 f. Such a change in current is detected by the current detection unit 50.

Further, the current detection unit 50 may be disposed on at least one of the wirings 201c to 201e to detect a current (current value i) flowing through the wirings 201c to 201 e.

Fig. 7 is a diagram in which 3 linear actuators 10b to 10d (10) are connected to a rectifier circuit Re and an inverter unit 40.

In the example shown in fig. 7, a connection point P1 between the diode D1 and the diode D2 is connected to the winding 11b (see fig. 2) of the linear actuator 10b via a wire 201D. The connection point P1 between the diode D1 and the diode D2 is also connected to the winding 11b of the linear actuator 10c via the wiring 201D. The windings 11b of the

linear actuators

10b and 10c may be connected to the connection point of the diodes D3 and D4.

Further, a connection point P1 between the diode D1 and the diode D2 is connected to the winding 11b of the linear actuator 10D via a wire 201 g.

That is, the linear actuators 10b to 10d are connected to the input side of a diode bridge circuit Re1 constituting the rectifier circuit Re.

Further, a connection point P2 between the switching elements S3 and S4 is connected to the winding 11b of the linear actuator 10d via a wire 201 h. That is, the linear actuator (first linear actuator) 10d is connected to the first arm corresponding to one phase in the three-phase full-bridge inverter constituting the inverter unit 40.

The connection between the wiring 201c and the wiring 201e is the same as that in fig. 6, and therefore, the description thereof is omitted. That is, the second arm corresponding to the other phase in the three-phase full bridge inverter constituting the inverter unit 40 is connected to the linear actuator (second linear actuator) 10 b. Further, the third arm corresponding to the remaining one phase is connected to the linear actuator (third linear actuator) 10 c. Here, the first arm is an arm including switching elements S3 and S4, the second arm is an arm including switching elements S1 and S2, and the third arm is an arm including switching elements S5 and S6.

By adopting such connection, 3 linear actuators 10 can be connected to 1 rectifier circuit Re and 1 inverter unit 40, and the cost can be suppressed.

Further, 4 or more linear actuators 10 may be connected to 1

inverter unit

40 and 1 rectifier circuit Re. In this way, the cost can be suppressed.

(acceleration/position estimating section 60, thrust adjusting section 90)

Next, the acceleration/position estimating unit 60 and the thrust adjusting unit 90 will be described with reference to fig. 1.

The acceleration/position estimating unit 60 and the thrust adjusting unit 90 are characteristic parts of the present embodiment.

The thrust adjusting Unit 90 and the acceleration/position estimating Unit 60 shown in fig. 1 are configured by circuits including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and various interfaces. The program stored in the ROM is read and developed into the RAM, and various processes are executed by the CPU.

Here, the control operation of each part will be described with reference to fig. 1.

As described above, when the object G (see fig. 1) vibrates, the stator 11 (see fig. 2) and the mover 12 (see fig. 2) of the linear actuator 10 relatively move. An induced voltage is then generated in the winding 11 b. The induced voltage causes a change in the current flowing through the inverter unit 40 and the wiring 201f shown in fig. 7. Such a change in current is detected by the current detection unit 50.

The acceleration/position estimation unit 60 in fig. 1 estimates the relative acceleration am and/or the relative position xm of the linear actuator 10 based on the current value i of the current detected by the current detection unit 50. Here, the relative acceleration am of the linear actuator 10 refers to the relative acceleration of the stator 11 and the mover 12 of the linear actuator 10 shown in fig. 2. Likewise, the relative position xm of the linear actuator 10 refers to a relative value of the stator 11 and the mover 12 of the linear actuator 10. At least one of the relative acceleration am and the relative position xm may be estimated.

The voltage equation of the linear actuator 10 is expressed by equation (1) where R [ omega ], L [ H ] and Em [ V ] are the resistance of the linear actuator 10. In addition, expression (1a) is obtained by transforming expression (1) with respect to induced voltage Em.

V＝Ri+L(di/dt)+Em……(1)

Em＝V-Ri-L(di/dt)……(1a)

Em＝ωm·Ke……(2)

Here, V is a voltage applied between terminals of the winding 11b of the linear actuator 10, and i is a current (current value i) flowing in the linear actuator 10.

The acceleration/position estimation unit 60 estimates the induced voltage Em from the expression (1a) by using the voltage command value V, which is an output of the voltage command generation unit 80, instead of the voltage V and using the current value i detected by the current detection unit 50 (the voltage command value V is substituted for V of the expression (1 a)).

The induced voltage Em is proportional to the relative speed ω m [ m/s ] of the mover 12 and the stator 11 of the linear actuator 10, and satisfies the relationship of expression (2). Here, Ke [ V · s/m ] is an induced voltage constant of the linear actuator 10. The induced voltage constant Ke of the linear actuator 10, the resistance R of the linear actuator 10, the inductance L of the linear actuator 10, and the like can be measured in advance.

The expression (2) is modified to a formula for ω m to obtain the following expression (2 a).

ωm＝Em/Ke……(2a)

Therefore, the acceleration/position estimation unit 60 estimates the relative velocity ω m based on the product of the equation (2a) and the inverse of the induced voltage constant Ke with respect to the induced voltage Em estimated by the equation (1 a). Then, the speed/position estimation unit 60 estimates the relative acceleration am by time-differentiating (d ω m/dt) the estimated relative speed ω m. The speed/position estimation unit 60 estimates the relative position xm by time-integrating ω m. The relative acceleration am and the relative position xm can be calculated from the following equations (3) and (4) by using the equations (1) and (2).

am＝(1/Ke)[(dV/dt)-R(di/dt)-L(d ² i/dt ² )]……(3)

As shown in fig. 1, the acceleration/position estimation unit 60 outputs the estimated relative acceleration am and the relative position xm to the current command generation unit 70.

(Current instruction generating section 70)

First, a specific configuration of the current command generating unit 70 will be described.

The current command generating unit 70 includes an m × gain multiplying unit 71, a k × gain multiplying unit 72, an adding unit 73, a current command value calculating unit 74, and a current command limiting unit 75.

First, the m gain multiplying unit 71 multiplies the relative acceleration am estimated by the acceleration/position estimating unit 60 by a predetermined gain m. As a result, the m gain multiplying unit 71 outputs the thrust command value Tm. The thrust command value Tm indicates the thrust to be output by the linear actuator 10.

Similarly, the k gain multiplying unit 72 multiplies the relative position xm estimated by the acceleration/position estimating unit 60 by a predetermined gain k. As a result, the k gain multiplying unit 72 outputs the thrust command value Tk.

Here, the gain m is a proportional gain for multiplying the relative acceleration am, and the gain k is a proportional gain for multiplying the relative position xm. The meaning of the gains m, k will be described later. In the first embodiment, the gains m and k are values determined by the designer and are constants.

Next, the adder 73 adds the thrust command value Tm and the thrust command value Tk to output the resultant as a thrust command value T. As described above, since it is only necessary to calculate one of the thrust command value Tm and the thrust command value Tk, either one of the thrust command value Tm and the thrust command value Tk is output as the thrust command value T. When both the thrust command value Tm and the thrust command value Tk are input to the adding unit 73, the average value of the thrust command value Tm and the thrust command value Tk may be output as the thrust command value T.

The current command value calculation unit 74 multiplies the thrust command value T input from the addition unit 73 by the reciprocal of the thrust constant Kt [ N/a ] of the linear actuator 10 to generate a current command value i.

When the current command value i is larger than the maximum current of the linear actuator 10, the inverter unit 40, and the like, the current command limiting unit 75 limits the current command value i and outputs a new current command value i after the limitation. The current command limiting unit 75 can be omitted. By providing such a current command limiting unit 75, it is possible to prevent an excessive current from flowing through the linear actuator 10 and the inverter unit 40.

(Voltage command generating section 80)

Next, the voltage command generation unit 80 will be described.

The voltage command generation unit 80 includes a subtraction unit 81 and a proportional-integral control unit 82.

The subtracting section 81 calculates a current deviation value Δ i, which is a difference between the current command value i generated by the current command limiting section 75 and the current (current value i) detected by the current detecting section 50.

Then, the Proportional-Integral control unit 82 calculates and outputs the voltage command value V by performing Proportional-Integral control (PI (Proportional-Integral) control) on the current deviation value Δ i.

By performing such control, feedback control by proportional-integral control is performed, and thereby control is performed so that the current value i coincides with (converges on) the current command value i.

The voltage command value V may be calculated by p (Proportional control) or PID (Proportional-Integral-Differential) control (Proportional-Integral-Differential control).

When the current value i coincides with the current command value i, the linear actuator 10 vibrates at the target amplitude and vibration frequency.

The voltage command value V is input to a pulse generator not shown. The pulse generator performs PWM control based ON the input voltage command value V, and switches ON/OFF the switching elements S1 to S6 shown in fig. 6. In this manner, the PWM-controlled voltage corresponding to voltage command value V is supplied to lines 201c to 201e shown in fig. 7.

By using such a proportional-integral control unit 82, control can be performed using a conventional technique.

(acceleration estimating unit 610)

The acceleration estimating unit 610 includes an induced voltage estimating unit 611, a 1/Ke calculating unit 612, a multiplying unit 613, and a differential calculating unit 614.

The induced voltage estimation unit 611 calculates the above equation (1a) based on the current value i detected by the current detection unit 50 and the voltage command value V output by the voltage command generation unit 80. That is, the induced voltage estimation unit 611 substitutes the voltage command value V into "V" of expression (1a) and substitutes the current value i into "i" of expression (1a) to calculate the induced voltage Em generated by the relative motion between the stator 11 (see fig. 2) and the mover 12 (see fig. 2) of the linear actuator 10.

The 1/Ke calculation unit 612 obtains the induced voltage constant Ke of the linear actuator 10 from a memory or the like not shown, and calculates the reciprocal thereof.

Then, the multiplying unit 613 multiplies the output (induced voltage Em) of the induced voltage estimating unit 611 by the output (1/Ke) of the 1/Ke calculating unit 612. The result output by the multiplying unit 613 is a result of substituting the formula (1a) into the induced voltage Em of the formula (2a), and is the relative velocity ω m between the stator 11 and the mover 12 of the linear actuator 10.

Next, the differential operation unit 614 differentiates the relative velocity ω m between the stator 11 and the mover 12 of the linear actuator 10, which is the output result of the multiplication unit 613. Thereby, the relative acceleration am (expression (3)) of the stator 11 and the mover 12 is calculated.

(position estimation unit 620)

The position estimating unit 620 includes an induced voltage estimating unit 621, a 1/Ke calculating unit 622, a multiplying unit 623, and an integration calculating unit 624.

The induced voltage estimating unit 621, the 1/Ke calculating unit 622, and the multiplying unit 623 in the position estimating unit 620 are the same as those in the units 611 to 613 shown in fig. 9, and therefore, the description thereof is omitted.

The integration calculator 624 integrates the relative velocity ω m of the stator 11 and the mover 12 of the linear actuator 10, which is the output result of the multiplier 623. Thereby, the relative position xm (expression (4)) of the stator 11 (see fig. 2) and the mover 12 (see fig. 2) is calculated.

The integral/differential operation in equations (3) and (4) is affected by an error in the current value i detected by the current detection unit 50, noise, an error between the voltage V actually applied and the voltage command value V ·, which is the output of the voltage command generation unit 80, and the like. Therefore, a low-pass filter and a high-pass filter may be provided.

< Effect of the first embodiment >

According to the first embodiment, the acceleration/position estimation unit 60 estimates and outputs the relative acceleration am and the relative position xm based on the current value i detected by the current detection unit 50.

The current command generating unit 70 calculates a thrust command value T and further calculates a current command value i based on the relative acceleration am and the relative position xm. Then, the voltage command generating unit 80 performs feedback control so that the current value i detected by the current detecting unit 50 follows the current command value i.

Here, the gain m and the gain k will be explained.

Here, a case is assumed where an object having a mass of m [ Kg ] is supported in parallel by a spring having a spring constant of k [ N/m ] and a damper having a damping coefficient of c [ Ns/m ], and a general vibration system having a single degree of freedom is configured and an excitation force F is applied to the vibration system.

Assuming that the displacement amount is x [ m ], the motion equation is given by the following equation (5), and the resonance frequency ω n [ rad/s ] thereof is given by equation (6).

m(d ² x/dt ² )+c(dx/dt)+kx＝F……(5)

ωn＝(k/m) ^1/2 ……(6)

According to equation (6), the resonance frequency ω n is determined by the mass m and the spring constant k.

For example, assuming that the object G shown in fig. 1 is a washing machine, the rotation speed of the washing tub changes constantly during washing, rinsing, and drying. As the rotation speed changes, the frequency of the vibration of the washing tub also changes. Therefore, when the rotation speed of the washing tub approaches the resonance frequency ω n, the vibration of the washing tub increases, which is propagated to the washing machine main body.

Here, the gain m for multiplying the relative acceleration am corresponds to the mass m in the equation of motion F ═ ma. Likewise, the gain k used to multiply the relative position xm corresponds to the spring constant k in the force F — kx experienced by the mass fixed to the spring.

According to the first embodiment, the thrust command value T is calculated by multiplying the relative acceleration am and the relative position xm of the linear actuator 10 by the predetermined gains m and k. That is, the force (thrust) to be generated can be controlled by adjusting the gain m corresponding to the mass in the equation of motion, and the force (thrust) to be generated can be controlled by the gain k corresponding to the spring constant (elastic coefficient). In other words, the set gains m and k correspond to changes in the mass of the washing machine, the spring constant of the spring 20 (see fig. 4) or the spring 20a (see fig. 5).

However, the gain m is different from the actual mass m. Similarly, the gain k is different from the spring constant k of the actual spring 20 (see fig. 4) or the spring 20a (see fig. 5).

In other words, the gains m and k are values determined by the designer as described above, and are set to values larger or smaller than the actual mass m and the spring constant k.

Thus, the thrust command value T output from the adder 73 becomes a thrust larger or smaller than the thrust actually output from the linear actuator 10. Accordingly, the vibration of the object G connected to the linear actuator 10 is shifted, and the vibration of the object G can be shifted from the resonance frequency.

Specifically, by using the gains m and k, the vibration frequency of the object G can be set to a frequency ω n represented by the following expression (7).

ωn＝[(k-k*)/(m-m*)] ^1/2 ……(7)

Equation (7) is satisfied under an ideal condition that the estimated relative acceleration am and the relative position xm are equal to the true value and the thrust command value T is accurately output.

In this way, if the object G is a washing machine, the resonance frequency ω n can be kept away from the rotation speed of the washing tub. Thus, a washing machine with low vibration and low noise can be provided. Further, if the object G is a washing machine, the force transmitted to the floor can be reduced during high-speed driving according to the first embodiment.

In addition, according to the first embodiment, only the current detection unit 50, i.e., the current sensor, is required as the sensor. That is, the first embodiment does not need to provide sensors for detecting the relative acceleration, relative position, and velocity of the mover 12 (see fig. 2 and 3).

That is, the linear actuator 10 generates the induced voltage Em due to the vibration of the object G, detects the vibration of the object G from the change in current due to the induced voltage Em, and performs vibration reduction of the object G based on the change in current. That is, since the linear actuator 10 is used as an acceleration sensor and a vibration sensor, it is not necessary to provide an acceleration sensor and a vibration sensor.

If more sensors are installed, the system will stop as a whole if 1 sensor fails. It is also not easy to ascertain which sensor is malfunctioning.

According to the first embodiment, only the current detection unit 50, i.e., the current sensor, is required as the sensor, so that the probability of the vibration control system Z stopping due to a sensor failure can be reduced. And it is easy to find out which sensor is malfunctioning.

In this manner, the vibration control system Z according to the first embodiment can achieve cost reduction. Further, since the components (the stator 11 and the mover 12) of the linear actuator 10 are hardly damaged or worn, the durability of the vibration control system Z can be improved.

As shown in fig. 6 and 7, the single-phase ac voltage applied to the plurality of linear actuators 10 is generated by one inverter unit 40. In this manner, cost reduction can be achieved compared to a configuration in which 2 inverter units are provided.

Thus, the vibration control system Z can appropriately suppress the vibration of the object G with a relatively simple configuration.

The vibration control system Z of the first embodiment includes a current command generation unit 70 that generates and outputs a current command value i to be supplied to the inverter unit 40 based on the relative acceleration am and/or the relative position xm. The vibration control system Z includes a voltage command generation unit 80 that generates a voltage command value V so that the current detected by the current detection unit 50 matches the current command. With this configuration, the vibration control of the object G can be easily performed.

In the first embodiment, the current command generating unit 70 multiplies the relative acceleration am and/or the relative position xm by predetermined gains m, k. In this way, the vibration control system Z virtually changes the mass of the washing machine and the spring constant of the

springs

20, 20a, causing the vibration frequency to change. That is, by adopting such a configuration, the vibration frequency of the object G can be easily changed based on the current value i.

Second embodiment

Next, a second embodiment of the present invention will be described with reference to fig. 11 to 16.

(vibration control System Za)

Fig. 11 is a diagram illustrating a configuration of a vibration control system Za used in the second embodiment.

The vibration control system Za shown in fig. 11 is different from the vibration control system Z shown in fig. 1 in that the current command generating unit 70 in fig. 1 is changed to a current command generating unit 70a of the thrust adjusting unit 90a of the vibration control device 100 a. The current command generating section 70a will be described later.

The other structures are the same as those in fig. 1, and therefore the same reference numerals are given thereto and the description thereof is omitted.

(Current instruction generating section 70a)

The current command generating unit 70a shown in fig. 12 is different from the current command generating unit 70 shown in fig. 8 in that the m × gain multiplying unit 71 is an m × gain multiplying unit 71a, and the k × gain multiplying unit 72 is a k × gain multiplying unit 72 a.

The m × gain multiplying unit 71a is different from the m × gain multiplying unit 71 in fig. 8 in that the gain m is variable. Similarly, the k × gain multiplying unit 72a is different from the k × gain multiplying unit 72 of fig. 8 in that the gain k is variable.

The other structures are the same as those in fig. 8, and the same reference numerals as those in fig. 8 are given thereto, and the description thereof is omitted.

As described above, the second embodiment is different from the first embodiment in that the magnitudes of the gains m and k are changed when the thrust command value T is generated from the output of the acceleration/position estimating unit 60.

(with respect to variable gain)

Fig. 13 shows a variation of the gains m and k.

In the example shown in fig. 13, the gains m, k vary with the polarity of the relative acceleration am or the relative position xm. In the example shown in fig. 13, when the relative acceleration am or the relative position xm is negative, the gains m and k are smaller than those when the relative acceleration am or the relative position xm is positive.

In fig. 14, the broken line indicates the temporal change in the relative acceleration am and the relative position xm of the linear actuator 10 caused by the vibration of the object G. The solid line represents a temporal change in the current value i flowing through the linear actuator 10 in order to suppress the vibration of the object G.

As shown in fig. 13, when the relative acceleration am or the relative position xm is negative, the control is performed such that the gains m and k are smaller than those when the relative acceleration am or the relative position xm is positive. Therefore, as shown in fig. 14, the current value i is smaller (in absolute value) when it is a negative value than when it is a positive value. Thus, even if the gains m and k are changed, the vibration of the object G can be appropriately suppressed.

Here, the relative acceleration am and the relative position xm are actually operated following the change in the current (current value i). However, since the operation is very complicated due to the influence of the structures of the object G and the linear actuator 10, the operation of the relative acceleration am and the relative position xm after the actual control is not shown in fig. 14. However, since the vibration is operated in accordance with the change in the current (current value i) as described above, when the relative acceleration am and the relative position xm are negative, the vibration amplitude is reduced as compared with the case where the relative acceleration am or the relative position xm is positive.

By performing such control, for example, when the space below and above the linear actuator 10 is narrow, the vibration amplitude in the space can be reduced.

Fig. 15 shows another example of changing the gain m or k.

When the relative acceleration am and the relative position xm are near zero, the polarities of the relative acceleration am and the relative position xm are alternately changed by noise or the like, and the vibration damping performance may be deteriorated. That is, when the relative acceleration am and the relative position xm are near zero, the current value i is also near zero. Therefore, the proportion of noise increases compared to the current value i. That is, the SN (Signal to noise) ratio decreases.

Then, as shown in fig. 15, when the relative acceleration am and the relative position xm are in the vicinity of zero, a dead zone is provided in which the gains m and k are 0.

In fig. 15, the width of the dead zone on the positive side of the gains m and k is different from the width of the dead zone on the negative side, but the dead zone may have the same width.

Fig. 16 also shows, similarly to fig. 14, the time change of the relative acceleration am and the relative position xm of the linear actuator 10 caused by the vibration of the object G by the broken line. The solid line represents a temporal change in the current value i flowing through the linear actuator 10 in order to suppress the vibration of the object G.

When the gains m and k are changed as shown in fig. 15, the relationship between the relative acceleration am, the relative position xm, and the current value i is as shown in fig. 16. That is, when the relative acceleration am and the relative position xm are near zero, the current value i is zero.

Here, the relative acceleration am and the relative position xm are actually operated following the change in the current (current value i). However, since the operation is very complicated due to the influence of the structures of the object G and the linear actuator 10, the operation of the relative acceleration am and the relative position xm after the actual control is not shown in fig. 16. However, since the operation follows the change in the current (current value i) as described above, the relative acceleration am and the relative position xm are controlled so as to substantially follow the operation of the current value i.

In this way, control at a position where the SN ratio of current value i is small can be avoided. This can appropriately suppress vibration of the object G. The current (current value i) shown in fig. 16 can be realized by controlling the gains m and k in the m × gain multiplying unit 71a and the k × gain multiplying unit 72a, by controlling the current command value calculating unit 74, and the like.

< Effect >

In the second embodiment, the gains m and k may be changed by the m × gain multiplying units 71a and k × gain multiplying unit 72 a. In this way, the current command value i can be changed according to the polarity, the magnitude, and the like of the relative acceleration am and the relative position xm. That is, appropriate vibration damping control can be provided according to the magnitude, direction, and vibration space of the vibration of the object G.

Third embodiment

Next, a third embodiment of the present invention will be described with reference to fig. 17 to 19.

(vibration control system Zb)

The vibration control system Zb shown in fig. 17 is different from the vibration control system Z shown in fig. 1 in the following 2 points.

(1) The current command generating unit 70b in the thrust adjusting unit 90b of the vibration control device 100b acquires information (vibration frequency information) on the vibration frequency f of the object G from the object G. However, when the object G is a rotating body, the rotational frequency may be acquired instead of the vibration frequency f.

For example, if the object G is a washing machine, the current command generating unit 70b detects a rotation frequency at which the vibration frequency f can be generated in the washing tub, based on a rotation command of a motor for rotating the washing tub or by using a sensor provided in the motor for detecting a rotation angle of the motor.

(2) The current command value i output by the current command generating unit 70b is limited based on the relative acceleration am calculated by the acceleration/position estimating unit 60, the relative position xm, and the acquired vibration frequency information. The current command generating section 70b will be described later.

The other structures are the same as those in fig. 1, and the same reference numerals as those in fig. 1 are assigned thereto, and the description thereof is omitted.

(Current instruction generating section 70b)

The current command generating unit 70b shown in fig. 18 is different from that shown in fig. 8 in the following 4 points.

(1) The thrust command generating unit 76a is provided in place of the m × gain multiplying unit 71.

(2) The k gain multiplying unit 72 is replaced with a thrust command generating unit 76 b.

(3) The thrust control device includes tables 77a and 77b to which the thrust

command generating units

76a and 76b refer, respectively. Table 77a stores the relative acceleration am, the vibration frequency f, the mass of the object G, the thrust command value Tm, and the like in association with each other. Table 77b stores relative position xm, vibration frequency f, the mass of object G, thrust command value Tk, and the like in association with each other. In the case where the object G is a washing machine, the mass of the object G is the mass of the washing machine and the mass of the laundry. Depending on the case, the mass of the linear actuator 10 may be included in the mass of the object G.

(4) The thrust command generating unit 76a outputs a corresponding thrust command value Tm with reference to the table 77a based on the input relative acceleration am and the vibration frequency information. Similarly, the thrust command generating unit 76b outputs a corresponding thrust command value Tk with reference to the table 77b based on the input relative position xm and vibration frequency information.

In this way, the thrust command generating unit 76a outputs the thrust command value Tm with the relative acceleration am and the vibration frequency information as inputs. This is essentially at the control gain m. Hereinafter, the thrust command generating unit 76a may be appropriately expressed as the control gain m.

Similarly, the thrust command generating unit 76b receives the relative position xm and the vibration frequency information as input, and outputs a thrust command value Tk. This is essentially at the control gain k. Hereinafter, the thrust command generating unit 76b may be appropriately expressed as the control gain k.

Note that the tables 77a and 77b may be combined into 1 table, and the thrust

command generating units

76a and 76b may refer to the table.

The other structure has the same structure as the current command generating unit 70 shown in fig. 8, and therefore the same reference numerals as those in fig. 8 are given to the other structure, and the description thereof is omitted.

The waveform 501 is a waveform in the case where the linear actuator 10 is not energized (the case where vibration damping control is not performed). That is, when no current is applied, the vibration amplitude becomes maximum at the resonance frequency ω n according to the relationship of equation (6).

Waveforms

502 and 503 show the results of controlling the linear actuator 10 by the method of the first embodiment.

Here, the waveform 502 represents a waveform in a case where the gain k is set so as to decrease the resonance frequency.

A waveform 503 indicates a waveform in a case where the gain k is adjusted so as to increase the resonance frequency.

Waveform 504 is the result of controlling the linear actuator 10 according to the third embodiment. Specifically, when the vibration frequency f is smaller than the resonance frequency ω n of the waveform 501, the gain k is controlled so that the resonance frequency increases (to be the waveform 503). After the vibration frequency f increases and exceeds the resonance frequency ω n of the waveform 501 (when it is larger than the resonance frequency ω n), the gain k is adjusted so that the resonance frequency decreases (becomes the waveform 502).

Fig. 19 shows the case where the gain k is controlled, but the gain m may be controlled similarly.

In this way, by changing the gain m or the gain k using the vibration frequency information from the object G, the vibration amplitude can be appropriately reduced.

< Effect >

According to the third embodiment, the thrust command value T is generated based on the vibration frequency information of the object G, and the increase of the vibration in the vicinity of the resonance frequency can be suppressed. For example, when the object G is the washing machine W, the relative acceleration of the linear actuator 10 may be different depending on the amount of laundry in the washing tub even if vibrations of the same vibration frequency are generated. The third embodiment can cope with such a situation. That is, the vibration control system Zb with high vibration damping performance can be provided.

Fourth embodiment

Next, a fourth embodiment of the present invention will be described with reference to fig. 20 to 23.

The fourth embodiment shows an example in which the vibration control system Z of the first to third embodiments is applied to a washing machine W.

(vibration control system Z)

The difference between fig. 20 and the vibration control system Z of fig. 1 is that the outer tub 37 of the washing tub W is provided in the linear actuator 10 as the object G of fig. 1.

And the rectifying circuit Re is originally provided in the washing machine W.

As shown in fig. 20, the rectifier circuit Re is connected to an inverter section 40, and also connected to an inverter section 38a that supplies electric power to a motor (first driving section) 38b, which motor 38 is used to rotate the washing tub 35 (refer to fig. 22).

(washing machine W)

Since the vibration control device 100 is provided inside the washing machine W, the vibration control device 100 is not illustrated in fig. 21.

The washing machine W shown in fig. 21 is a drum-type washing machine W, and has a laundry drying function. The washing machine W includes a base 31, a casing 32, a door 33, an operation/display panel 34, and a drain hose H.

The base 31 supports the housing 32.

The housing 32 includes left and right side plates 32a, a front face cover 32b, a back face cover 32c (refer to fig. 22), and a top face cover 32 d. A circular inlet h1 (see fig. 22) for taking and placing laundry is formed near the center of the front cover 32 b.

The door 33 is an openable and closable cover provided at the inlet h 1.

The operation/display panel 34 is a panel provided with an electric switch, an operation switch, a display, and the like, which is provided on the top surface cover 32 d.

The drain hose H is a hose for draining the washing water in the outer tub 37 (refer to fig. 22), and is connected to the outer tub 37.

Fig. 22 is a vertical cross-sectional view of washing machine W provided with vibration control device 100. The washing machine W includes, in addition to the above structure, a washing tub 35, a lift rib 36, an outer tub 37, a driving mechanism 38, and an air blowing unit 39.

The washing machine W is also provided with a control microcomputer C. The control microcomputer C controls various parts of the washing machine W, including an inverter unit 40, an acceleration/position estimation unit 60, a thrust adjustment unit 90, and the like shown in fig. 20. Note that, control lines indicating control performed by the control microcomputer C are not shown in order to prevent the drawing from becoming complicated.

In fig. 22, the ac power supply E and the rectifier circuit Re are not shown.

The washing tub 35 accommodates laundry and has a bottomed cylindrical shape. The washing tub 35 is enclosed in the outer tub 37 and is supported by the outer tub 37 so as to be rotatable coaxially therewith. A large number of through holes (not shown) for water and air are provided in the peripheral wall and the bottom wall of the washing tub 35. In addition, the opening h2 of the washing tub 35 faces the door 33 in the closed state together with the opening h3 of the outer tub 37.

In the example shown in fig. 22, the rotation center axis of the washing tub 35 is inclined so that the opening side is higher, but is not limited thereto. That is, the rotation center axis of the washing tub 35 may be horizontal or vertical.

The lifting ribs 36 lift and drop the laundry during washing and drying, and are provided on the inner circumferential wall of the washing tub 35.

The outer tub 37 is a bottomed cylindrical shape for storing washing water and the like. As shown in fig. 22, the outer tub 37 encloses the washing tub 35. The linear actuator 10 (stator 11, mover 12) and the spring 20 are provided on both the left and right sides of the outer tub 37. Fig. 6 shows one of the 2 linear actuators 10.

A drain hole (not shown) is provided in the lowermost portion of the bottom wall of the outer tub 37, and a drain hose H is connected to the drain hole. Accordingly, the washing water is stored in the outer tub 37 in a state where a drain valve (not shown) provided in the drain hose H is closed, and the washing water is discharged by opening the drain valve.

The driving mechanism 38 is a mechanism for rotating the washing tub 35, and is provided outside the bottom wall of the outer tub 37. The drive mechanism 38 includes an inverter portion 38a and a motor 38b for driving the motor 38b shown in fig. 20. A rotation shaft of a motor 38b (see fig. 20) of the driving mechanism 38 penetrates through a bottom wall of the outer tub 37 and is coupled to a bottom wall of the washing tub 35.

The blowing unit 39 blows hot air to the washing tub 35, and is disposed at an upper side of the washing tub 35. The air blowing unit 39 includes a heater (not shown) and a fan (not shown). Thus, the air heated by the heater is blown into the washing tub 35 by the fan. Thereby, the laundry containing moisture is gradually dried in the washing tub 35.

(rectifier circuit Re, inverter 40)

Fig. 23 is different from fig. 6 in that the output of the rectifier circuit Re is supplied to the inverter unit 40, and is also supplied to the motor driving inverter unit 38a that supplies a three-phase ac voltage to the motor 38b for rotating the washing tub 35 (see fig. 22), as described above. In this way, it is not necessary to separately prepare the rectifier circuit Re, and the cost can be reduced.

The other structures are the same as those in fig. 6, and therefore, the same reference numerals are given thereto and the description thereof is omitted.

As described above, the rectifier circuit Re is originally provided in the washing machine W.

Here, fig. 20 to 23 show an example in which the vibration control system Z of the first embodiment is applied to the washing machine W, but the vibration control system Za of the second embodiment and the vibration control system Zb shown in the third embodiment may be applied.

< Effect >

According to the fourth embodiment, the inverter section 40 and the inverter section 38a share the rectifier circuit Re. That is, the rectifier circuit Re originally provided in the washing machine W can be used for controlling the linear actuator 10. This makes it possible to provide a washing machine W having a low-cost vibration control system Z. Further, vibration can be reduced even in the washing machine W in which the rotation speed and the weight of laundry are changed in a complicated manner.

In each embodiment, as shown in fig. 4 and 5, the

springs

20 and 20a are provided between the linear actuator 10 and the fixing jig J, but the present invention is not limited thereto. For example, a mechanism using rubber or hydraulic pressure may be applied instead of the spring 20.

The fourth embodiment describes a configuration in which vibration control of washing machine W is performed by vibration control device 100 or the like, but the present invention is not limited to this configuration. For example, the first to third embodiments of the present invention can be applied to household electric appliances such as air conditioners and refrigerators, and to objects that vibrate such as railway vehicles, automobiles, construction machines, buildings, elevators, and compressors.

In addition, although the embodiments have been described with respect to the structure in which the linear actuator 10 is driven by the single-phase ac power, the linear actuator 10 may be driven by the three-phase ac power, for example.

The present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above embodiments have been described in detail to facilitate understanding of the present invention, but the present invention is not limited to the embodiments having all the configurations described. A part of the structure of one embodiment may be replaced with the structure of another embodiment, and the structure of another embodiment may be added to the structure of one embodiment. Further, a part of the configuration of each embodiment can be added, deleted, or replaced with another configuration.

Note that each of the above-described structures, functions,

parts

60, 90, memory units, and the like may be partially or entirely realized by hardware, for example, by designing an integrated circuit. As shown in fig. 4, the above-described structures, functions, and the like may be realized by software by a processor such as a CPU interpreting and executing a program for realizing the functions. The information such as the programs, tables 77a, 77b, and files for realizing the functions may be stored in the hd (hard disk), a memory, a recording device such as ssd (solid State drive), or a recording medium such as ic (integrated circuit) card, sd (secure digital) card, or dvd (digital Versatile disk), in addition to the hd (hard disk).

In addition, the control lines and the information lines in each embodiment represent parts necessary for description, and do not necessarily represent all the control lines and the information lines in a product. In practice it can also be considered that almost all structures are interconnected.

Description of the reference numerals

10. 10a to 10d Linear actuator (drive part, second drive part)

11. 11a stator

12. 12a mover

35 washing barrel

37 outer barrel

Inverter part of 38a washing machine

38b Motor (first drive part)

40 inverter part (power conversion part) of vibration control device

50 current detection unit

60 acceleration/position estimating unit (estimating unit)

70. 70a, 70b current command generating part

71. 71a m gain multiplying part

72. 72a k gain multiplying part

74 Current command value calculation unit

75 current command limiting unit

76a, 76b thrust command generating unit

77a, 77b table

80 Voltage instruction generating part

82 proportional integral control part

90. 90a, 90b thrust adjusting part

100. 100a, 100b vibration control device

E AC power supply

G object

Re rectifier circuit (rectifier)

Re1 diode bridge circuit

W washing machine

Z, Za vibration control system

Claims

1. A vibration control system, comprising:

a driving unit including a mover and a stator, and connected to an object capable of vibrating;

a current detection unit that detects a current value of the current flowing in the drive unit;

an estimation unit that estimates a relative acceleration and/or a relative position of the mover and the stator of the drive unit based on the current value detected by the current detection unit; and

a thrust adjusting unit that adjusts a thrust of the driving unit based on the relative acceleration and/or the relative position estimated by the estimating unit,

the thrust adjusting portion includes:

a current command generation unit that generates a current command to be output to the drive unit based on the relative acceleration and/or the relative position; and

a voltage command generation unit that generates a voltage command value to be output to a power conversion unit that drives the drive unit, the voltage command value being such that the current detected by the current detection unit matches the current command,

the current command generation unit generates the current command by multiplying the relative acceleration and/or the relative position by a predetermined proportional gain, and changes the magnitude of the proportional gain in accordance with the vibration frequency of the object in accordance with the relative acceleration and/or the relative position.

2. The vibration control system of claim 1, wherein:

the current command generation unit changes the amplitude of the current command in accordance with the relative acceleration and/or the polarity of the relative position.

3. A vibration control system as claimed in claim 1, wherein:

the current command generation unit sets the current command to zero when the relative acceleration and/or the relative position is near zero.

4. The vibration control system of claim 1, wherein:

the current command generation unit limits the magnitude of the absolute value of the current command.

5. The vibration control system of claim 1, wherein:

supplying power to the driving unit via a rectifying unit that rectifies an alternating-current voltage supplied from a power supply and a power converting unit that converts the voltage rectified by the rectifying unit into an alternating-current voltage,

the plurality of driving units are connected to 1 of the power conversion units, and connected to 1 of the rectifying units as necessary.

6. The vibration control system of claim 5, wherein:

the driving part comprises a first linear actuator, a second linear actuator and a third linear actuator,

the rectifying part is a diode bridge circuit,

the power conversion section is a three-phase full-bridge inverter,

the first linear actuator, the second linear actuator and the third linear actuator are connected to an input side of the diode bridge circuit,

a first linear actuator is connected to a first leg of the three-phase full-bridge inverter corresponding to one,

a second linear actuator is connected to a second leg of the three-phase full-bridge inverter corresponding to the other,

a third linear actuator is connected to a third leg of the three-phase full-bridge inverter corresponding to the remaining one.

7. A washing machine, characterized by comprising:

a washing tub for receiving laundry;

an outer tub enclosing the washing tub; and

a first driving part for rotating the washing tub,

and, the washing machine further includes:

a second driving part including a mover and a stator, and connected to the tub;

a current detection unit that detects a current flowing in the second drive unit;

an estimation unit that estimates a relative acceleration and/or a relative position of the mover and the stator in the second drive unit based on the current value detected by the current detection unit; and

a thrust adjusting unit that adjusts thrust of the second driving unit based on the relative acceleration and/or the relative position estimated by the estimating unit,

the thrust adjusting portion includes:

a current command generation unit that generates a current command to be output to the second drive unit based on the relative acceleration and/or the relative position; and

a voltage command generation unit that generates a voltage command value to be output to a power conversion unit that drives the second drive unit, the voltage command value being such that the current detected by the current detection unit matches the current command,

the current command generation unit generates the current command by multiplying the relative acceleration and/or the relative position by a predetermined proportional gain, and changes the magnitude of the proportional gain according to the relative acceleration and/or the relative position and the vibration frequency of the outer tub.

8. The washing machine as claimed in claim 7, wherein:

the first and second driving units are supplied with electric power via a rectifying unit that rectifies an alternating-current voltage supplied from a power supply and a power converting unit that converts the voltage rectified by the rectifying unit into an alternating-current voltage.