JP2002018178A - Controller for washing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller for a washing machine which prevents the occurrence of out-of-step with a fluctuation in the load torque to a DC brushless motor. SOLUTION: The phase shift quantity which is the shift between the phase of the sine-wave-like voltage generated when the sine-wave-like voltage of a prescribed set frequency is supplied to a motor 9 in starting spin-drying operation and the phase of a position signal detected by a Hall sensor 63 is detected and the waveform of the sine-wave-like voltage is shifted in a direction where the phase shift quantity is decreased according to the fluctuation in the phase shift quantity. The counter-electromotive force generated from a motor 9 by the phase shift is regenerated to an inverter circuit 57 side and when the DC voltage detected by an inverter input voltage detecting means 65 increases, the wavelength of the sine-wave-like voltage is shifted in the direction where the phase shift quantity is decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a washing machine.

[0002]

2. Description of the Related Art Induction motors are mainly used as motors in washing machines, but DC brushless motors have been used in order to reduce the electromagnetic noise of the motor and save energy. In a DC brushless motor, it is necessary to supply a sinusoidal voltage to the motor in synchronization with the rotor position.

For this reason, when the number of rotations of the motor such as washing and stirring is low, feedback control (synchronous operation) for detecting the rotor position and controlling the sinusoidal voltage supplied to the motor is performed. On the other hand, when the motor speed such as dehydration is high, the rotor position is detected and the feedback control is performed, so that the control timing of the sinusoidal voltage supplied to the motor is shifted due to an attachment error of the rotor position detection means and the like, Generally, a sinusoidal voltage having a predetermined frequency set in advance is supplied to the motor to perform open-loop driving (asynchronous operation).

[0004]

However, when the motor load is large or the commercial power supply voltage is low, the motor torque tends to be insufficient, and the rotor position tends to be delayed with respect to the sinusoidal voltage supplied to the motor. In the worst case, it caused a step-out phenomenon and stopped.

Further, when switching from the feedback drive to the open loop drive during the spin-drying operation, there is a case where the frequency of the sinusoidal voltage supplied to the motor suddenly changes to cause a step-out.

As a prior art for reducing the phase shift between the rotor position and the sinusoidal voltage supplied to the motor to prevent the step-out phenomenon from occurring, there is known a P-sinusoidal voltage supplied to the motor.
There is a washing machine control device that increases the WM duty, that is, increases the amplitude of the sinusoidal voltage supplied to the motor to recover the delay in the rotor position.

However, in such a control device, since the motor output torque is changed, the rotation speed of the motor becomes uneven. In addition, the following speed when the phase shift amount between the rotor position and the sinusoidal voltage supplied to the motor changes according to the change in the frequency of the sinusoidal voltage supplied to the motor is not constant, but varies according to the amount of clothing. Very complicated feedback control is required. In addition, since a motor capable of producing a large output torque is required, the cost increases.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a control device for a washing machine in which a step-out phenomenon does not occur even when the motor load increases.

In addition, the present invention provides a method for removing a motor load even if the motor load periodically fluctuates due to, for example, a shift in clothes during dewatering in a drum type washing machine having a horizontal drum rotating about a substantially horizontal axis. It is an object of the present invention to provide a control device for a washing machine in which a tone phenomenon does not occur.

Another object of the present invention is to provide a control device for a washing machine in which a step-out phenomenon does not occur even when switching from field-back control to open-loop control, and smooth switching can be performed. .

[0011]

In order to achieve the above object, in a control device for a washing machine according to the present invention, a DC brushless motor for driving a rotating body for washing, and an inverter for controlling the rotational driving of the motor. Control means, and a position detecting means for detecting a rotor position of the motor, a sine wave voltage of a predetermined set frequency is applied to the motor during a spin-drying step of rotating the washing rotator and spin-drying the clothes. A phase shift between the phase of the sinusoidal voltage and the phase of the position signal detected by the position detecting means, which is generated when the voltage is supplied and driven in open loop, is detected. When the amount exceeds the threshold value, the waveform of the sine wave voltage is shifted by a predetermined shift amount in a direction to reduce the phase shift amount.

Further, in addition to the above configuration, the inverter control means may be configured to vary the shift amount according to a change in the phase shift amount.

[0013] In addition to the above configuration, the inverter control means includes an AC voltage supplied from a commercial AC power supply and the AC voltage.
A voltage detecting means for detecting at least one of the DC voltage and the DC voltage rectified by the rectifying means, and the lower the voltage detected by the voltage detecting means, the smaller the phase shift amount threshold value or the more the shift amount. May be made larger.

Further, in addition to the above configuration, a configuration may be adopted in which the phase shift amount is continuously detected a plurality of times, and the average value of the detected phase shift amounts is compared with the phase shift amount threshold.

Further, in addition to the above configuration, a configuration may be employed in which a plurality of the phase shift amount thresholds are set according to the number of rotations of the motor.

Further, in addition to the above configuration, a configuration may be adopted in which the set frequency of the sinusoidal voltage is not updated when the phase shift amount exceeds the phase shift amount threshold value. Further, in a state where the set frequency of the sine wave voltage is not updated, when the phase shift amount does not exceed the phase shift amount threshold continuously for a predetermined period, the set frequency of the sine wave voltage is updated. A configuration that makes it possible is also possible.

In addition to the above configuration, when the voltage detected by the voltage detecting means exceeds a preset voltage threshold value, the phase shift amount does not exceed the phase shift amount threshold value. The configuration may be such that the waveform of the sinusoidal voltage is shifted according to the amount.

Also, in the control device for a washing machine according to the present invention, a DC brushless motor for driving a washing rotating body, an inverter control means for controlling the rotational driving of the motor, and detecting a rotor position of the motor. In a control device for a washing machine having a position detecting means, a spinning voltage is synchronized with a position signal from the position detecting means during a spin-drying step of rotating the washing rotator and centrifugally spin-drying the garment. When switching from the feedback drive supplied to the motor to the open loop drive supplying a sine wave voltage of a predetermined frequency to the motor, the initial phase of the sine wave voltage in the open loop drive is changed to the sine wave voltage in the feedback drive. A configuration in which the phase is shifted with respect to the last phase of the waveform voltage may be employed.

In addition to the above configuration, the inverter control means includes an AC voltage supplied from a commercial AC power source and the AC voltage.
A voltage detection unit that detects at least one of a C voltage and a DC voltage rectified by a rectification unit, and sets an initial phase of the sine-wave voltage in the open-loop drive to a final phase of the sine-wave voltage in the feedback drive. A plurality of shift amounts and shift directions when the phase is shifted with respect to the phase are set in accordance with the number of rotations of the motor or the voltage detected by the voltage detection means when switching from the feedback drive to the open loop drive. It may be configured.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. In the present embodiment, the present invention is applied to a drum type washing machine having a horizontal drum that rotates about a substantially horizontal axis, but includes a vertical dehydration tank that rotates about a substantially vertical axis. The present invention can be applied to a washing machine which is used.

FIG. 1 is an external perspective view of a drum type washing machine according to an embodiment of the present invention. The exterior 1 of the main body, which forms the outer wall of the washing machine, can be opened and closed with a door 3 at the front. An operation panel 11 provided with operation keys and a display unit is provided on an upper part of the front surface of the main body exterior unit 1.

FIG. 2 is a side sectional view of the drum type washing machine. A bottomed water tank 4 having an opening 4a on the front surface is arranged in the main body exterior part 1. As shown in FIGS. 6 and 7, the water tank 4 is elastically supported by a first suspension device 7 a and a second suspension device 7 b formed of a tension spring in the exterior body 1.

An angle 29a is attached to the inner wall of the body exterior part 1 at the upper front part of the water tank 4, and an angle 29b is attached to the back wall of the body exterior part 1 at the upper part. Angles 30a and 30b are fixed to the front and back surfaces of the water tank 4. Then, the first suspension device 7a is hung on the angles 29a and 30a, and the front part of the water tank 4 is suspended at two places on the left and right by the first suspension device 7a.

Similarly, the angle 29b and the angle 30b
A second suspension device 7b is mounted on the water tank 4, and a rear portion of the water tank 4 is suspended at two places on the left and right by the second suspension device 7b. Further, the first and second suspension devices 7a and 7b are mounted to be symmetrically inclined by angles θ1 and θ2 with respect to the vertical direction, respectively. Thereby, the water tank 4 can be centered on sliding in the left-right direction. In addition, angle 30
a and 30b may be integrally formed with the water tank 4.

Further, the water tank 4 is supported on the bottom of the outer case 1 by an attenuating device comprising dampers 8a and 8b. Dampers 8a are attached at two places on the left and right in front of the water tank 4, and dampers 8b are provided at two places on the left and right behind the water tank 4.
Is attached. Thereby, the swing of the water tank 4 is attenuated.

A cushioning member 28 made of felt, rubber, or the like is fixed to the back wall of the main body exterior part 1. This allows
When the water tank 4 slides in the front-rear direction, the occurrence of noise due to the collision between the water tank 4 and the back wall of the main body exterior unit 1 is prevented.

A drum 5 is provided in the water tank 4.
The drum 5 is fixed to the shaft 5e, and the motor case 9
a shaft part 5 on a bearing 6 integrated with the water tank 4 through a
e is supported and is rotatable. A rotor 9b is fixed to the shaft portion 5e, and a stator 9c is fixed in the motor case 9a. These constitute a motor 9 for driving the drum 5. The rotational drive of the motor 9 is controlled by the control device 2 described later. In the present embodiment, a three-phase 20-pole DC brushless motor is used as the motor 9.

The rotor 9b of the motor 9 has a structure as shown in FIG. 11, and is rotatably held concentrically inside a stator 9c shown in FIG. The rotor core 71 is made of laminated steel plates. A permanent magnet 72 is disposed between the salient poles 71A of the rotor core 71. By reversing the arrangement of the N pole 72N and the S pole 72S of the adjacent permanent magnet 72, the salient pole portion 71A of the rotor core becomes the N pole 71
The N and S poles 71S alternate. With such a configuration, a higher magnetic force can be obtained than in a configuration in which a permanent magnet is circumferentially attached to a rotor core.

The motor 9 has 20 poles, and the salient pole portion 71A of the rotor core has 10 N poles and 10 S poles.
The present invention is not limited to the number of poles. Also,
The configuration of the rotor is not limited to the present invention. For example, a configuration may be adopted in which a permanent magnet is circumferentially attached to the rotor.

FIG. 12 shows the stator 9c provided in the motor cover 9a. The stator 9c has 24 poles, and the stator core 73 is formed of a laminated steel sheet similarly to the rotor core 71. A winding 74 is wound around the stator core 73 in a concentrated winding manner. The concentrated winding method does not limit the present invention. For example, the winding may be wound around the stator core by a lap winding method. Also, the rotor 9b and the stator 9
c, a Hall sensor (not shown) is provided fixed to the motor cover 9a.
The north pole and south pole of A are detected.

Although the present embodiment is a direct drive system in which the drum 5 and the motor 9 are directly fixed, a belt drive system in which the motor rotational torque is transmitted to the drum 5 by a belt and a pulley may be used.

A small hole 5a is provided on the entire peripheral wall of the drum 5. The small holes 5a allow washing water to flow between the water tub 4 and the drum 5 during washing. A baffle 5b is provided on the inner wall surface of the drum 5 so as to protrude therefrom. The laundry is hooked and lifted by the rotation of the drum 5 and dropped into the washing liquid to perform washing.

A liquid balancer 5d is provided on the outer peripheral edge of the opening 5c on the front surface of the drum 5. Liquid balancer 5d
Is filled with a liquid such as salt water, and when the drum 5 rotates, the fluid moves to cancel the shift of the center of gravity due to the bias of the laundry and the washing liquid. The liquid balancer 5d may be provided on the inner peripheral edge of the drum 5.

The rotation axis y-y of the drum 5 is inclined such that the depth of the drum 5 is lowered by an angle θ with respect to the horizontal axis. Thereby, when the user stands and puts the laundry in and out of the drum-type washing machine, the user has a better view to the inside of the drum 5 and the laundry can be easily taken in and out.

A packing 10 made of an elastic material such as rubber or resin is attached to the periphery of the laundry inlet 1a and the opening 4a of the water tub 4 so as to form a passage. Packing 1
Reference numeral 0 denotes a structure in which the inner peripheral edge 10a is in close contact with the peripheral edge of the door 3 when the door 3 is closed. Thereby, waterproofing during the washing operation is performed. The packing 10 is adapted to bend in response to the swing of the water tank 4 due to bellows or the like, and to follow the packing.

A water supply pipe 12 connected to a water pipe is provided in an upper part of the main body exterior part 1. Water supply pipe 12
When the water supply valve 13 provided in the middle of the
Water supply nozzle 1 attached to packing 10 via 4
From 5, tap water is supplied into the water tank 4.

Drain duct 1 led out from the bottom of water tank 4
6 is provided with a connection case 17 in which a lint filter 17a is provided in the middle of the pipe and a drainage pump 18, and has a structure in which the washing liquid from the water tub 4 is drained to the outside of the main body exterior part 1. The lint filter 17a is formed by, for example, forming a resin in a lattice shape or forming fine fibers in a bag shape, and accumulating lint and the like in the washing liquid. And can be detached from the lower part of the front surface of the main body exterior part 1.

A water level sensor 23 is provided above the connection case 17 from the air trap 22 via a dynamic pressure pipe 21. The water level sensor 23 moves the magnetic body within the coil according to the pressure change in the air trap 22. The resulting change in inductance of the coil is detected as a change in oscillation frequency, and the water level in the water tank 4 is detected.

Further, the drum type washing machine may have a structure as shown in a side sectional view shown in FIG. The same components as those in FIG. 2 are denoted by the same reference numerals. A circulation duct 19 branched from the drain duct 16b is provided on the outlet side of the connection case 17. The circulation duct 19 is connected to the packing 10 so as to face the opening 4 a of the water tank 4, and has a circulation pump 20 in the middle of the pipe.

Therefore, when the drain pump 18 is stopped and the circulation pump 20 is driven, the water tank 4, the drain duct 16a,
A circulation path to the water tank 4 through the connection case 17, the drain duct 16b, the circulation pump 20, and the circulation duct 19 is formed. By circulating the washing liquid in the tub 4 through this circulation path, the detergent in the washing liquid is sufficiently dissolved, and the lint filter 17a removes lint and the like. Thereby, the reattachment of the lint to the laundry can be prevented.

Further, the drum type washing machine may have a structure as shown in a side sectional view shown in FIG. The same components as those in FIG. 2 are denoted by the same reference numerals. Above the water tub 4, a drying unit 24 including a blower fan 25 and a heater 26 for drying the laundry is provided. The drying unit 24 is provided with a cooling duct 27 for connecting an outlet 4b facing the opening 4a of the water tank 4 and a circulation port 4c provided at a lower portion.
Is located in the middle of the route. Further, a cooling device (not shown) is provided in the cooling duct 27.

In the above configuration, the control device 2 for controlling the operation of the drum type washing machine is disposed on the back of the operation panel 11. The control device 2 will be described with reference to FIG.

The control device 2 comprises a main control device 50 and a sub control device 51. The main control unit 50 stores a program such as an operation content of each process such as washing, rinsing, and dehydration, and an execution sequence of the processes (that is, a processing course), and opens and closes the water supply valve 13 and the drain pump 18 according to the program. And the motor 9 is controlled via the sub control unit 51.

The main control unit 50 inputs a signal such as a reservation for washing from the operation panel 11 and outputs a signal for displaying the progress of the operation to the operation panel 11. The main control unit 5
0 sounds the buzzer 52 at the end of washing or the like. Further, the main control unit 50 inputs a signal indicating the water level in the water tank 4 from the water level sensor 23.

The main control unit 50 transmits a signal S1 necessary for controlling the rotation of the motor 9 to the sub control unit 51 together with a synchronization clock CLK. After receiving the signal S1, the sub control unit 51 reads the signal S1 and then outputs the clock CLK.
The signal S2 is transmitted to the main control unit 50 in synchronization with.

Next, the configuration of the sub control unit 51 will be described with reference to FIG. The AC voltage output from the commercial power supply 53 is supplied to the rectifier circuit 55 via the reactor 54, and is converted into a pulsating DC by the rectifier circuit 55. In the rectifier circuit 55,
Diode bridges are used.

The DC rectified by the rectifier circuit 55 is smoothed by smoothing capacitors 56a and 56b. Capacitor 5
The + terminal of 6a is connected to the + terminal of the rectifier circuit 55. The minus terminal of the capacitor 56a and the plus terminal of the capacitor 56b are connected to the minus output terminal of the commercial power supply 53. The negative terminal of the capacitor 56b is connected to the negative output terminal of the rectifier circuit 53. Capacitors 56a, 56b
Is supplied to the inverter circuit 57. Inverter circuit 57 converts DC into three-phase AC.

The inverter circuit 57 includes six NPN transistors 58a to 58c, 59a as switching means.
59c is a three-phase full-wave bridge configuration. Then, the six transistors 58a to 58c, 59a to 59
The diodes 60a to 60c and 61a are respectively connected in parallel to c.
To 61c are connected. Transistors 58a-58
The connection points a, b, and c between c and the transistors 59a to 59c are connected to the stator coils Lu, Lv, and Lw of each phase (U phase, V phase, and W phase) of the motor 9. The bases of the transistors 58a to 58c and 59a to 59c are connected to the drive circuit 62.

The motor 9 has Hall sensors 63a, 63b, 63c for detecting the rotational position of the rotor 9b.
The rotor position signals Hu, Hv, Hw output from the Hall sensors 63a, 63b, 63c are input to the microcomputer 64.

The microcomputer 64 outputs the drive signal P1
To P6 are output to the drive circuit 62. Drive circuit 6
2 performs PWM chopping of the drive signals P1 and P2 at several to several tens of kHz and amplifies the drive signals P1 and P2.
8a and 59a, drive signals P3 and P4 are PWM-chopped and amplified at several to several tens of kHz and supplied to the bases of transistors 58b and 59b, respectively, and drive signals P5 and P6 are several to several tens of kHz. PWM chopping and amplification at each transistor 5
8c, 59c.

The rotor position signals Hu, Hv, Hw and the sinusoidal voltage E supplied to the stator coils Lu, Lv, Lw
The microcomputer 64 sends the drive signals P1 to P6 to the drive circuit 6 so that the phases of the drive signals P1 to
2 to control the rotation of the motor 9 is called synchronous operation.

On the other hand, the microcomputer 6 controls the sine-wave voltages Eu, Ev, Ew to an arbitrary set frequency.
When the motor 4 outputs the drive signals P1 to P6 to the drive circuit 62 to control the rotation of the motor 9 by open loop driving, it is called asynchronous operation.

Reference numeral 65 denotes an inverter input voltage detecting means for inputting the voltage of the connection node between the resistors R1 and R2 and detecting the input voltage of the inverter circuit 57. The detection output is sent to the microcomputer 64.

The main control unit 50 stores the operation chart shown in FIG. 5 as a program, and executes a washing operation according to the program.

When the laundry is thrown in from the laundry inlet 1a and the opening / closing door 3 is closed, the inner peripheral edge 10a of the packing 10 is brought into close contact with the peripheral edge of the opening / closing door 3, and the water tub 4 is sealed. When the detergent is put in the detergent case 14 and the operation panel 11 is operated, a signal S1 is sent from the main control unit 50 to the sub control unit 51. The sub-control unit 51 sets the motor 9 to 70 based on the signal S1.
Operate asynchronously for a predetermined time at rpm. At this time, a deviation occurs between the signal phases of the rotor position signals Hu, Hv, Hw and the sinusoidal voltages Eu, Ev, Ew applied to the stator 9c (hereinafter, this deviation is referred to as a phase deviation amount).

FIG. 13A shows the waveform of the sinusoidal voltage Eu applied to the U-phase, and FIGS. 13B to 13D show the rotor position signal Hu. The rotor position signal H shown in FIG.
u ′ is a signal waveform when the synchronous operation is performed, and the pulse edge of the rotor position signal Hu ′ coincides with the zero cross of the sinusoidal voltage Eu. The rotor position signal Hu ″ shown in (c) is a signal waveform when the load torque is increased in the state where the open loop drive is being performed and the asynchronous operation is being performed. The rotation of the rotor position signal Hu ″ and the sinusoidal voltage Eu is caused by a phase shift amount δ1 because the rotation is slightly delayed with respect to the voltage phase applied to the winding 74. In the present embodiment, the phase shift amount is detected using the U phase, but another phase or a plurality of phases may be used. Although FIG. 13 shows only one electrical angle period, the motor used in the present embodiment has 20 poles, so that the N-pole and the S-pole are paired and a sinusoidal voltage of 10 cycles per rotation of the rotor. Eu.

When the clothes in the drum are in a state of being offset,
Since a difference in load torque occurs when lifting the leaning garment during drum rotation and when the leaning garment is lowered,
The phase shift amount δ1 of the rotor position signal Hu ″ with respect to the sinusoidal voltage Eu of 10 periods during one rotation of the drum increases or decreases. The shift amount of the clothing can be detected based on the change in the phase shift amount δ1, such that the difference between the maximum value and the minimum value of the phase shift amount δ1 increases as the amount of shift of the clothing increases. It should be noted that the phase shift amount δ1 is not only delayed, but also when the deviating garment comes down, the weight of the garment causes the drum to exceed the motor driving speed, and as shown in (d), the leading direction from the sinusoidal voltage Eu. Phase shift amount δ1
May occur. If the amount of clothing is large, the rotational load torque is large. Therefore, if it is detected that the average value of the phase shift amount δ1 is slightly delayed with respect to the sine wave voltage Eu compared to when the amount of clothing is small, Can be detected.

As shown in FIG. 10, the average value of the phase shift amount in one rotation of the motor increases as the weight installed in the drum increases. FIG. 10 shows a PWM of a sinusoidal voltage supplied to the motor 9 when the rotation speed of the motor 9 is 80 rpm.
The characteristics when the duty is 120 are shown. Therefore, the greater the amount of clothing put into the drum 5, the heavier the clothing, the greater the average value of the phase shift amount δ1. Thus, the amount of clothing put into the drum can be detected from the amount of phase shift.

The rotation speed of the motor 9 and the PWM duty of the sinusoidal voltage supplied to the motor 9 when detecting the amount of clothing are not limited to the values used in the present embodiment, but may vary depending on the diameter and shape of the drum 5. A suitable value may be set accordingly.

When the amount of clothes is detected, the main controller 50 stores in advance the rotation speed, the reversal time and the reversal period of the drum 5 in the washing, rinsing, dehydrating and drying steps based on the amount of the clothes. It is determined from the rotation chart, and further, the operation time until the completion of the drying operation is predicted. This makes it possible to perform an optimal washing operation according to the amount of clothing. The washing operation will be described below with reference to FIG.

First, the “washing step” is started according to the washing chart. In the water supply operation of the “washing step”, the open / close door 3 is locked and the water supply valve 13 is opened. Based on the opening of the water supply valve 13, the tap water is supplied to the water tank 4 and the drum 5 together with the detergent from the water supply nozzle 15 via the detergent case 14.
Flow into. Then, the water level in the water tank 4 is determined to be a predetermined water level according to the amount of clothing detected by the amount of phase shift. When the predetermined water level is reached, the water level sensor 23
And outputs a detection signal to the main control unit 50. The main control unit 50 closes the water supply valve 13 and sends a signal S1 to the sub control unit 51 based on the washing chart. The sub control unit 51 receives the signal S1
The "washing operation" is performed for a predetermined time by controlling the motor 9 for rotating and driving the drum 5 based on. This predetermined time is also determined based on the amount of clothing detected by the amount of phase shift.

When the "washing step" is completed, the process shifts to a "rinsing step" in which "rinse dewatering operation" and "stirring and rinsing operation" are alternately repeated a plurality of times. In the “rinsing step”, first, the drainage pump 18 is operated to perform a draining operation of draining the washing liquid to the outside of the main body exterior unit 1 through the drainage duct 16 and the connection case 17. When the draining operation is completed, the control device 2 drives the motor 9 based on the first dehydration chart. As a result, the drum 5 rotates to perform a “rinse dehydration operation”. The washing liquid of the laundry is projected to the inner wall of the water tub 4 through the small holes 5a provided on the entire peripheral wall of the drum 5 by the centrifugal force caused by the spinning rotation. The washing liquid that has flowed down to the lower portion of the water tub 4 along the inner wall is drained to the outside via the drain duct 16.

If the amount of displacement of the clothes in the drum 5 is large, abnormal vibration occurs in the high-speed rotation operation in the "rinse dehydration operation", and in the worst case, the washing machine falls. For this reason, before shifting to the high-speed rotation operation, dehydration is performed by gradually increasing the number of revolutions at a low rotation, and the clothes are moved around the inner periphery of the drum 5 so that the amount of bias of the clothes becomes sufficiently small. After evenly sticking to the surface, high-speed rotation operation is performed.

In the “rinse dehydration operation”, the number of rotations of the drum 5 is gradually increased so that the clothes in the drum 5 are evenly applied. When the amount of displacement of the clothes is large, the phase shift shown in FIG. The amount δ1 increases, and in an extreme case, a step-out phenomenon occurs.

Further, even if the low-speed rotation in which the clothes are evenly applied is ended and the operation shifts to the high-speed rotation operation, the vibration of the drum 5 increases at the rotation speed of the drum corresponding to the resonance frequency of the vibration, and the load torque increases. The phase shift amount δ1 becomes large, and a relatively large load torque fluctuation of several to several tens of seconds occurs due to a pulsation phenomenon even in high-speed spinning, and the phase shift amount δ
1 may increase, and in an extreme case, a step-out phenomenon may occur.

In order to prevent such a step-out phenomenon, the microcomputer 64 shifts the phase of the sinusoidal voltage supplied to the motor 9 as shown in the timing chart of FIG. FIG.
4 (a) and (c) are sinusoidal voltages E applied to the U phase.
FIGS. 14B and 14D show the waveform of u, respectively, and the rotor position signal Hu.

First, the case where the sinusoidal voltage Eu is as shown in FIG. 14A and the rotor position signal Hu is as shown in FIG. 14B will be described. In the meantime, the determination of the waveform shift of the sinusoidal voltage Eu is performed in all the sections from T1 to T3.
In order to explain the effect of shifting the waveform of the sine wave voltage Eu, it is determined that the waveform of the sine wave voltage Eu is shifted only in the section T2.

The section T1 is a section in which the determination of the waveform shift of the sine wave voltage is not performed. At this time, the sine wave voltage Eu rises and the rising pulse edge time of the rotor position signal Hu (t0) with respect to the zero crossing time (t0).
1) is delayed by 90 °, the phase shift amount δ1 is 90 °
become.

The section T2 is a section in which the determination of the waveform shift of the sinusoidal voltage is performed. The waveform of the sinusoidal voltage is shifted based on the flowchart of FIG. First, in step # 10, the phase shift amount threshold δ _th and the amplitude A _th of the sinusoidal voltage Eu at a position where the phase is delayed by the phase shift amount threshold δ _th from the rising zero cross are set. In the present embodiment, the phase shift amount threshold δ _th is set to 30 °.

In the next step # 20, the sinusoidal voltage E
It is determined whether or not u is at the rising zero crossing position. If the sinusoidal voltage Eu is at the position of the rising zero cross (Y in step # 20), the measurement is started after setting the phase amount θ from the rising zero cross to zero (step # 30). In FIGS. 14A and 14B, since the result of step # 20 becomes Y at time t2, the measurement of the phase amount θ from the rising zero crossing starts at time t2.

In the next step # 40, it is determined whether or not a rising pulse edge of the rotor position signal Hu has appeared. If the rising pulse edge of the rotor position signal Hu appears (Y in step # 40), the phase shift amount δ1 between the sinusoidal voltage Eu and the rotor position signal Hu is smaller than the phase shift amount threshold _δth . In this case, the process proceeds to step # 10 without shifting the waveform of the sine wave voltage Eu, and the phase shift between the sine wave voltage Eu and the rotor position signal Hu in the next cycle is measured.

On the other hand, if the rising pulse edge of the rotor position signal Hu does not appear (N in step # 40), the phase amount θ from the rising zero-cross is equal to the phase shift amount threshold δ.
It is determined whether or not it is less than _th (step # 50). The phase amount θ from the rising zero cross is the phase shift amount threshold δ
If it is less than _th (Y in step # 50), step # 4
Move to 0. If the phase amount θ from the rising zero cross is not equal to or smaller than the phase shift amount threshold δ _th (N in step # 50), the phase shift amount δ1 between the sinusoidal voltage Eu and the rotor position signal Hu exceeds the phase shift amount threshold δ _th . Will be.
In FIGS. 14A and 14B, at time t3, step #
Since N becomes 50, it is determined that the waveform of the sinusoidal voltage Eu is shifted at time t3.

In the next step # 60, it is determined whether or not a rising pulse edge of the rotor position signal Hu appears.

The rising pulse of the rotor position signal Hu
If a voltage appears (Y in step # 60), a sinusoidal voltage
The output value of Eu rises from the zero cross and the phase shift amount threshold
Value δ _thAmplitude A at a position where the phase is delayed_thShift up to
Step # 70). As a result, the sine wave voltage Eu has a phase
Shift amount δ1 and phase shift threshold value δ_thIn the phase lag direction by the difference
The waveform is translated. That is, the phase shift amount δ1
The waveform shift amount of the sinusoidal voltage Eu varies according to the variation.
You.

The sine-wave voltages Ev and Ew are delayed by 240 ° and 120 ° with respect to the sine-wave voltage Eu after shifting the waveform of the sine-wave voltage Eu in the same manner as before the waveform shift, respectively. The waveform shifts similarly to the waveform voltage Eu.

Thereafter, the process proceeds to step # 10, and the phase shift is measured in the next cycle. In FIGS. 14A and 14B, the rising pulse edge of the rotor position signal Hu appears at time t4, so that the sinusoidal voltage E at time t4.
The amplitude of u is changed to _Ath . As a result, the waveform of the sine wave voltage Eu is shifted in the direction of phase delay of 60 ° at the time point t4.

The section T3 is a section in which the determination of the waveform shift of the sine wave voltage is not performed. At this time, the rising pulse edge time of the rotor position signal Hu (t5) with respect to the rising zero crossing time (t5) of the sine wave voltage Eu.
6) is delayed by 30 °, the phase shift amount δ1 is 30 °
become.

The sine-wave voltages Ev and Ew are delayed by 240 ° and 120 ° with respect to the sine-wave voltage Eu after the sine-wave voltage Eu is shifted in the same manner as before the waveform shift, respectively. The waveform shifts similarly to the waveform voltage Eu.

In the section T2, the operation as shown in the flowchart of FIG.
The angle is reduced from 90 ° at 1 to 30 ° at section T3, so that the step-out phenomenon can be prevented.

Further, in the operation as shown in the flowchart of FIG. 15, since the frequency of the sinusoidal voltage is not changed, the step-out phenomenon can be prevented without changing the rotation speed of the motor 9. Therefore, there is no influence on the dewatering performance determined by the rotation speed of the motor 9, and a stable dewatering performance can be obtained.

By setting the threshold value of the phase shift amount so as to be variable in accordance with the amount of clothing and the number of rotations of the motor 9 during spin-drying, the waveform of the sinusoidal voltage can be shifted smoothly, and Intermittent sounds and fluctuations in rotation can be reduced. In addition, the motor 9 has a characteristic that an efficient phase shift angle changes according to the number of rotations during the open-loop driving, so that the phase shift angle is corrected to a higher efficiency to save energy. You can also plan. In the present embodiment, the U phase is used as a reference, but a V phase, a W phase, or a plurality of phases may be used.

Next, the case where the sinusoidal voltage Eu is as shown in FIG. 14C and the rotor position signal Hu is as shown in FIG. 14D will be described. In the meantime, the determination of the waveform shift of the sinusoidal voltage Eu is performed in all the sections from T1 to T3.
In order to explain the effect of shifting the waveform of the sine wave voltage Eu, it is determined that the waveform of the sine wave voltage Eu is shifted only in the section T2.

The section T1 is a section in which the determination of the waveform shift of the sinusoidal voltage is not performed. At this time, the sine wave voltage Eu rises and the zero crossing time point (t10)
The rising pulse edge of the rotor position signal Hu (t)
11) is delayed by 90 °, the phase shift amount δ1 is
As in the case of (a) and (b) of FIG.

The section T2 is a section in which the determination of the waveform shift of the sinusoidal voltage is performed. The waveform shift of the sine wave voltage is performed based on the flowchart of FIG. First, in step # 310, the phase shift amount threshold δ _th and the amplitude A _th of the sinusoidal voltage Eu at a position delayed in phase by the phase shift amount threshold δ _th from the rising zero cross are set. In the present embodiment, the phase shift amount threshold δ _th is set to 30 °.

In the next step # 320, it is determined whether or not the sinusoidal voltage Eu is at the rising zero crossing position. If the sinusoidal voltage Eu is at the position of the rising zero cross (Y in step # 320), the measurement is started after setting the phase amount θ from the rising zero cross to zero (step # 330). In FIGS. 14C and 14D, t
At time t12, the result of step # 320 becomes Y, and measurement of the phase amount θ from the rising zero crossing starts at time t12.

In the next step # 340, it is determined whether or not a rising pulse edge of the rotor position signal Hu has appeared. If a rising pulse edge of the rotor position signal Hu appears (Y in step # 340), the sinusoidal voltage Eu
Is coincident with the rising pulse edge of the rotor position signal Hu, and the phase shift amount δ1 becomes zero. In this case, the process proceeds to step # 310 without shifting the waveform of the sinusoidal voltage Eu, and the phase shift between the sinusoidal voltage Eu and the rotor position signal Hu in the next cycle is measured.

On the other hand, if the rising pulse edge of the rotor position signal Hu does not appear (N in step # 340),
The amplitude of the sinusoidal voltage Eu is set to zero (step # 35)
0).

In the next step # 360, it is determined again whether a rising pulse edge of the rotor position signal Hu has appeared. If the rising pulse edge of the rotor position signal Hu does not appear (N in step # 360), the process proceeds to step # 350 to maintain the amplitude of Eu at zero.

On the other hand, if a rising pulse edge of the rotor position signal Hu appears (Y in step # 360), the flow shifts to step # 370 to determine whether or not the phase amount θ from the rising zero cross is equal to or less than the phase shift amount threshold δ _th . Is determined.

If the phase amount θ from the rising zero cross is equal to or smaller than the phase shift amount threshold δ _th (Y in step # 370), the process proceeds to step # 390, where the waveform of the sinusoidal voltage Eu stored in the microcomputer 64 is stored. , The amplitude of the sinusoidal voltage Eu is changed to the amplitude of the current phase amount θ. Thereafter, the process proceeds to step # 310, and the phase shift is measured in the next cycle.

On the other hand, if the phase amount θ from the rising zero cross is not smaller than the phase shift amount threshold δ _th (step # 3)
70 N), the phase shift amount δ1 of a sinusoidal voltage Eu and the rotor position signals Hu is to exceed the phase shift amount threshold value [delta] _th. In FIGS. 14C and 14D, N of step # 370 is reached at time t14, so that it is determined that the waveform of the sinusoidal voltage Eu is shifted at time t14.

In the next step # 400, the output value of the sinusoidal voltage Eu is shifted from the rising zero cross to the amplitude A _th at a position where the phase is delayed by the phase shift amount threshold δ _th . Thus, the sinusoidal voltage Eu has a waveform that is translated in the phase delay direction by the difference between the phase shift amount δ1 and the phase shift threshold δ _th .

The sine-wave voltages Ev and Ew are delayed by 240 ° and 120 ° with respect to the sine-wave voltage Eu after the sine-wave voltage Eu is shifted in the same manner as before the waveform shift, respectively. The waveform shifts similarly to the waveform voltage Eu.

Thereafter, the flow shifts to step # 310, where a phase shift measurement in the next cycle is performed. In FIG. 14 (c) (d), have changed the amplitude of the sinusoidal voltage Eu to A _th at the t14 time. As a result, the waveform of the sine wave voltage Eu is shifted in the phase delay direction by 60 ° at time t14.

The section T3 is a section in which the determination of the waveform shift of the sine wave voltage is not performed. At this time, the sine wave voltage Eu rises and the zero crossing point (t15)
The rising pulse edge of the rotor position signal Hu (t)
16) is delayed by 30 °, the phase shift amount δ1 is 30 °.
°.

In the section T2, the operation as shown in the flowchart of FIG.
Is 90 ° in section T1 to 30 ° in section T3
The step-out phenomenon can be prevented beforehand.

The operation of the flowchart of FIG. 19 is easier to control than the operation of the flowchart of FIG. 15, but the sine wave voltage Eu becomes zero between t12 and t14,
The sinusoidal voltage supplied to the motor 9 does not change smoothly. For this reason, noise is increased as compared with the operation of the flowchart of FIG.

When the AC voltage supplied from commercial power supply 53 is high, the DC voltage supplied to inverter circuit 57 also increases. In this case, the sinusoidal voltage E supplied to the motor 9
Since u, Ev, and Ew also increase, the motor torque increases, and even if the phase shift amount δ1 is large, the step-out phenomenon hardly occurs. Therefore, the phase shift amount threshold δ _th may be set to be large.

On the other hand, when the AC voltage supplied from the commercial power supply 53 is low, the DC voltage supplied to the inverter circuit 57 is also low. In this case, a sinusoidal voltage Eu supplied to the motor 9, Ev, Ew becomes small motor torque decreases, since the phase shift amount δ1 step-out phenomenon is likely to occur even if small, the phase shift amount threshold [delta] _th is small It is better to set to.

Therefore, the inverter input voltage detecting means 65
By adjusting the phase shift amount threshold value δ _th in accordance with the voltage detection signal, more appropriate control can be realized. Further, the amount of translation shift of the sinusoidal voltage waveform may be corrected by the voltage detection signal of the inverter input voltage detection means 65.
A voltage detecting means for detecting the AC voltage output from the commercial power supply 53 is provided, and the phase shift amount threshold δ is determined based on the AC voltage supplied from the commercial power supply 53 instead of the DC voltage supplied to the inverter circuit 57. _The shift amount of the parallel movement of the waveform of the _th or sinusoidal voltage may be adjusted.

The above-described parallel shift of the waveform of the sine-wave voltage Eu is performed based on the phase shift amount δ1 detected every time a rising pulse edge of the rotor position signal appears. In the detection of the rising pulse edge, when external noise is superimposed on the rotor position signal, the rising pulse edge of the rotor position signal may be erroneously detected and controlled. For this reason, a stable control performance can be obtained by performing the parallel shift of the waveform of the sinusoidal voltage in accordance with the average value of the phase shift amount δ1 a plurality of times. The operation of the microcomputer 64 in this case will be described with reference to the flowchart in FIG.

First, in step # 110, the phase shift amount threshold δ _th and the amplitude A _th of the sinusoidal voltage Eu at a position delayed in phase by the phase shift amount threshold δ _th from the rising zero cross are set.

In the next step # 120, the number of measurements n is set to 1, and the routine goes to step # 130. Step # 13
At 0, it is determined whether or not the sine-wave voltage Eu is at the rising zero-cross position. If the sinusoidal voltage Eu is at the position of the rising zero cross (Y in step # 130), the phase amount θ from the rising zero cross is set to zero, and then the measurement is started (step # 140).

In the next step # 150, it is determined whether or not a rising pulse edge of the rotor position signal Hu has appeared. When the rising pulse edge of the rotor position signal Hu appears (Y in step # 150), the phase amount θ from the rising zero cross at that time is stored as the phase shift amount δ1 _n (step # 160).

At the next step # 170, it is determined whether or not the number of measurements n has reached a predetermined number of measurements K for measuring the average value. If the number of measurements n has not reached the number of measurements K for the average value measurement (N in step # 170), the process proceeds to step # 180, and the value obtained by adding 1 to the number of measurements n is stored as a new number of measurements n. Thereafter, the process proceeds to step # 130 to continue the measurement.

[0106] On the other hand, if the number of measurements n has reached the number of measurements K for average measurement (Y in Step # 170), stored in that δ1 _1, δ1 _2, ..., from .delta.1 _K, the phase shift amount The average value of δ1 is calculated (step # 190).

In the next step # 200, the phase shift amount δ
It is determined whether the average value of 1 is equal to or less than the phase shift amount threshold δ _th . The average value of the phase shift amount δ1 is equal to the phase shift amount threshold δ _th
If not (Y in step # 200), the waveform of the sine-wave voltage Eu is not shifted in parallel by step # 11.
Move to 0.

On the other hand, if the average value of the phase shift amount δ1 is not equal to or smaller than the phase shift amount threshold δ _th (N in step # 200),
It is determined whether a rising pulse edge of the rotor position signal Hu appears (step # 210).

When the rising pulse edge of the rotor position signal Hu appears (Y in step # 210), the output value of the sinusoidal voltage Eu is raised and the amplitude A _th at the position where the phase is delayed by the phase shift amount threshold δ _th from the zero crossing. (Step # 220). Thereby, the sinusoidal voltage Eu
Is a waveform shifted in parallel in the phase delay direction by the difference between the average value of the phase shift amount δ1 and the phase shift threshold value δ _th . Thereafter, the process proceeds to step # 110, and the next phase shift measurement is performed.

The sine-wave voltages Ev and Ew are delayed by 240 ° and 120 ° with respect to the sine-wave voltage Eu after the sine-wave voltage Eu is shifted in the same manner as before the waveform shift, respectively. The waveform shifts similarly to the waveform voltage Eu.

Even if the sine wave voltage waveform is shifted in parallel as described above, the voltage supplied from the commercial power supply 53 is extremely low or the load torque is continuously increased during acceleration of the high-speed spinning operation. when large or, in some cases the phase shift amount δ1 exceeds continuously the phase shift amount threshold value [delta] _th.

[0112] signal S1 thus phase shift amount δ1 is the case exceeds continuously the phase shift amount threshold [delta] _th, by temporarily stopping the acceleration of a high-speed dewatering rotation operation, i.e., sent from the main control unit 50 Is stopped and the sinusoidal voltage of the set frequency is continuously supplied to the motor 9, so that the torque required for acceleration becomes unnecessary, and the phase shift amount δ1 gradually decreases.

As a result, it is possible to prevent the actual decrease in the number of revolutions due to the parallel shift of the waveform of the sinusoidal voltage being continuously performed in each cycle. This is because, even if the set frequency itself of the sine wave voltage supplied to the motor 9 is fixed, the actual cycle becomes shorter if the parallel shift is performed every cycle continuously. This is because the vehicle decelerates.

As described above, after temporarily stopping the operation based on the signal S1 sent from the main control unit 50 and temporarily stopping the acceleration of the high-speed spinning rotation, the phase shift amount δ is continuously continued for a predetermined period.
When 1 becomes equal to or smaller than the phase shift amount threshold δ _th , the main control unit 5
The operation based on the signal S1 sent from 0 is performed, the set frequency of the sinusoidal voltage is updated, and acceleration is started. As a result, energy can be saved without using unnecessary torque. Further, since unnecessary torque is not required, it is not necessary to use a motor capable of outputting a large torque, and the size of the motor can be reduced.

The description so far has been about the case where the phase of the rotor 9b lags behind the phase of the sinusoidal voltage supplied to the motor 9, that is, the case where the load torque is larger than the motor torque. When the rotor 9b is rotating up to the rotational speed, the phase of the rotor 9b may fluctuate back and forth with respect to the phase of the sinusoidal voltage supplied to the motor 9 due to a rhythm phenomenon caused by the vibration system. .

When the phase of the rotor 9b lags behind the phase of the sinusoidal voltage supplied to the motor 9, it can be dealt with by shifting the parallel waveform of the sinusoidal voltage supplied to the motor 9 as described above. Even when the phase of the rotor 9b advances with respect to the phase of the sinusoidal voltage supplied to the motor 9, the phase shift can be corrected by shifting the waveform of the sinusoidal voltage supplied to the motor 9 in parallel.

However, when the phase of the rotor 9b advances with respect to the phase of the sinusoidal voltage supplied to the motor 9, a counter electromotive voltage is generated in the stator winding of the motor 9 and the capacitor 5
The regenerative current flows into 6a and 56b, and the DC voltage detected by the inverter input voltage detecting means 65 rises. In the worst case, the DC voltage is reduced by the transistors 58a to 58c.
59a-59c and diodes 60a-60c, 61a-
61C, transistors 58a-58c,
59a-59c and diodes 60a-60c, 61a-
61c may be destroyed.

[0118] Therefore, when the phase of the rotor 9b during dewatering operation proceeds to the phase of the sinusoidal voltage supplied to the motor 9, sinusoidal performed when the phase shift amount δ1 exceeds a phase shift threshold value [delta] _th in addition to shifting the translation of voltage waveforms when the DC voltage detected by the inverter input voltage detection unit 65 exceeds a voltage threshold which is previously set angular amount δ1 them phase is less than the phase shift amount threshold value [delta] _th The transistors 58a to 58c and 59a to 59c are also provided by immediately shifting the parallel movement of the waveform of the sinusoidal voltage.
And the diodes 60a to 60c and 61a to 61c can be prevented from being damaged or destroyed.

Since the control device for a washing machine according to the present embodiment includes a voltage doubler rectifier circuit as shown in FIG. 9, the DC voltage input to the inverter circuit 57 is usually 280 [V] or less. However, if the phase of the rotor 9b advances with respect to the phase of the sinusoidal voltage supplied to the motor 9 during the high-speed spinning operation and a back electromotive voltage is generated, the DC voltage input to the inverter circuit 57 becomes 500 [V]. It rises immediately to the vicinity.

In this case, if the parallel movement is shifted based on the average value of the phase shift amount δ1 as in the operation of the flowchart of FIG. The DC voltage is the rated voltage of the transistors 58a-58c, 59a-59c and the diodes 60a-60c, 61a-61c (600
[V]), the translation shift is performed immediately when it reaches about 80% (480 [V]).

Since the rhythm phenomenon during the high-speed dehydration operation occurs at a specific rotation speed determined by a vibration prevention mechanism or the like, changing the rotation speed of the motor 9 can slightly suppress the rhythm. If the number of rotations of the motor 9 is reduced, the dewatering performance will be reduced, and if the number of rotations of the motor 9 is increased, noise and vibration will increase. On the other hand, in the present embodiment in which the parallel movement of the waveform of the sine wave voltage is shifted in accordance with the DC voltage input to the inverter circuit 57, such a problem does not occur because the rotation speed of the motor 9 does not change.

The PWM duty of the sinusoidal voltage supplied to the motor 9 in the open-loop driving is set in advance for each rotation speed. When the PWM duty is set to be relatively large, the phase shift amount δ1 becomes small,
Power consumption increases. Considering this, the drum 5
Depending on the rated capacity and shape of the motor and the output characteristics of the motor 9,
What is necessary is just to set the PWM duty to an optimum value.

In the “rinse dehydration operation”, the number of revolutions of the motor 9 is increased stepwise from low rotation, and the clothes are evenly stuck on the inner peripheral surface of the drum 5. At the time of rotation start, a large starting torque is required because the wet clothes are solidified at the lower part of the drum 5. Therefore, in order to reliably start the motor, as shown in FIG. 16, the motor 9 is started and rotated (at time t ₁ ) by feedback driving (synchronous operation) to increase the rotation speed and increase the rotational inertia of the drum 5. time point is switched to (t ₂ time) in an open loop drive (asynchronous operation), to a maximum rotational speed (t ₃ time points) is rotated raised, then to high speed dehydration completion (t ₄ time) common to open-loop drive It is a driving method.

In the feedback drive, the PWM duty of the sinusoidal voltage supplied to the motor 9 is changed in order to maintain the rotation speed of the motor 9 at the target rotation speed.
The PWM duty is undefined.

[0125] On the other hand, in an open loop drive, PWM duty is fixed assigned to each set rotational speed, setting the rotational speed of the open-loop drive at the time point of switching from the feedback driven open loop drive (t ₂ time) feedback It matches the target rotation speed in driving.

[0126] PWM Therefore, when the motor rotational speed immediately before the switching from the feedback driven open loop drive is close to the target rotational speed, at the time of switching from the feedback driven open loop drive (t ₂ time)
The duty hardly changes.

[0127] On the other hand, if the motor rotational speed immediately before the switching from the feedback driven open loop drive is away from the target rotational speed, P at time (t ₂ time) for switching from the feedback driven open loop drive
The WM duty changes rapidly. However, even if the PWM duty changes abruptly, the rotation speed of the motor 9 is not
And does not change suddenly due to the rotational inertia of clothing and clothing.

If the phase of the rotor 9b in the feedback drive immediately before switching to the open loop drive is ahead of the phase of the sinusoidal voltage supplied to the motor 9, the rotation speed of the motor 9 is higher than the target rotation speed in the feedback drive. It is getting bigger.

In this case, at the time (t ₂ ) when switching from the feedback drive to the open loop drive, the rotational speed of the motor 9 does not change suddenly, but the set rotational speed of the open loop drive is different from the target rotational speed in the feedback drive. Since they are the same, the phase of the rotor 9b leads the phase of the sinusoidal voltage supplied to the motor 9. For this reason, a step-out phenomenon is likely to occur.

When the phase of the rotor 9b in the feedback drive immediately before the switching to the open loop drive is behind the phase of the sine wave voltage supplied to the motor 9, the rotation speed of the motor 9 is reduced to the target in the feedback drive. It is smaller than the rotation speed.

In this case, the rotation speed of the motor 9 does not change abruptly at the time of switching from the feedback drive to the open loop drive (time t ₂ ), but the set rotation speed of the open loop drive is the target rotation speed in the feedback drive. Therefore, the phase of the rotor 9b is delayed with respect to the phase of the sinusoidal voltage. For this reason, the step-out phenomenon easily occurs.

When the phase of the rotor 9b is advanced with respect to the phase of the sinusoidal voltage, a lagging force is generated on the rotor 9b by the field of the stator 9c. Therefore, in the next cycle, the rotor 9b is pulled back in the delay direction due to the reaction. As a result, the phase of the rotor 9b moves forward and backward with respect to the phase of the sinusoidal voltage supplied to the motor 9. The rotor 9b due to such a vibration phenomenon and the bias of the clothes in the drum 5 during the open loop drive.
, The step-out phenomenon is more likely to occur.

Therefore, by shifting the phase of the sine wave voltage of the open loop drive at the time (t ₂ ) when switching from the feedback drive to the open loop drive,
Avoid step-out phenomenon.

For example, when the rotation speed immediately before switching from feedback drive to open loop drive is faster than the set rotation speed for open loop drive, the phase of the sine wave voltage of open loop drive when switching from feedback drive to open loop drive is changed. Proceed. If the rotation speed immediately before switching from the feedback drive to the open loop drive is faster than the set rotation speed of the open loop drive, the phase of the sine wave voltage of the open loop drive when switching from the feedback drive to the open loop drive is delayed. This makes it possible to reduce the amount of phase shift between the sine wave voltage and the rotor position signal after switching from the feedback drive to the open loop drive, thereby suppressing the above-described vibration phenomenon.

FIG. 17 is a timing chart in the case where the rotation speed immediately before switching from the feedback drive to the open loop drive is larger than the set rotation speed during the open loop drive.

(A) is the PWM duty average value of the sinusoidal voltage applied to the motor 9 for each cycle, (b) is the rotor position signal Hu, and (c) is the phase from feedback drive to open loop drive switching. (D) shows a sinusoidal voltage Eu 'when no shifting is performed, and (d) shows a sinusoidal voltage Eu' when performing phase shifting from feedback driving to open-loop driving switching. Further, the interval of t ₁₀ ~t ₃₀ is subjected to feedback drive, interval t ₃₀ ~t ₄₀ is performing open-loop drive. Thus, the point at which t ₃₀ is switched from the feedback driven open loop drive.

First, the sinusoidal voltage Eu in the case where the phase is not shifted from the feedback driving shown in (c) to the open loop driving switching will be described.

The PWM duty in the section from t _{10 to} t ₂₀ is t
Although lower against ₁₀ previously, this is because the PWM duty is set to slightly lower for t ₁₀ rpm previous rotor 9b is greater than the target rotational speed of the feed-back driving.

Since the PWM duty has been reduced, t ₁₀
Period T1 sinusoidal voltage Eu in the interval of ~t ₂₀ is
The period becomes longer than the period (T ₀ ) corresponding to the target rotation speed. And, in a section of t ₁₀ ~t ₂₀ for the rotational speed of the rotor 9b is smaller than the target rotational speed, in a section of the next t ₂₀ ~t ₃₀ is changed to increase the PWM duty. Since the PWM duty is increased, the period T2 of the sinusoidal voltage Eu in the interval of t ₂₀ ~t ₃₀ is shorter than the cycle corresponding to the target revolution speed (T _0). Further, as the PWM duty becomes higher, the peak value of the sinusoidal voltage Eu becomes t
It is higher by the ₁₀ ~t ₂₀ section. As described above, the feedback drive is performed by determining the PWM duty in the next cycle according to the difference between the actual rotation speed of the rotor 9b and the target rotation speed.

In the section from t _{10 to} t ₃₀ , feedback driving is performed, so that the rising pulse edge of the rotor position signal Hu and the rising zero cross of the sinusoidal voltage Eu supplied to the motor 9 are synchronized.

[0141] When switched to the open loop drive from the feedback driven by t ₃₀ time, setting the rotational speed of the normal open loop driving as described above, it is set equal to the target rotational speed of the feed-back driving. Further, PWM duty during open-loop drive (t ₃₀ ~t ₄₀₎ is set higher. Thereby, a motor torque sufficient to maintain a stable rotation speed can be secured.

Here, at the time of open-loop drive after switching from feedback drive to open-loop drive (t _30-
At t ₄₀ ), a sine-wave voltage Eu having a frequency (T ₀ ) corresponding to the set number of revolutions is supplied to the motor 9, but the number of revolutions of the rotor 9 b changes immediately due to the rotational inertia of the drum 5 and the clothes. Instead, the cycle of the rotor position signal Hu remains almost the same as the cycle T2 at the time of feedback drive immediately before switching from feedback drive to open-loop drive. For this reason, in the next cycle, the rising pulse edge of the rotor position signal Hu leads the phase by θ1 with respect to the rising zero cross of the sinusoidal voltage Eu. This phase shift θ
If 1 is large, a step-out phenomenon will occur.

Therefore, it is preferable to supply the motor 9 with a sinusoidal voltage Eu 'as shown in FIG. Sinusoidal voltage E
u ′ is obtained by advancing the phase of the sinusoidal voltage by θ2 at the time (t ₃₀ ) when switching from the feedback drive to the open loop drive. As a result, in the next cycle, the rising pulse edge of the rotor position signal Hu is advanced in phase by θ3 with respect to the rising zero cross of the sine-wave voltage, and the phase shift θ1 in the sine-wave voltage Eu shown in FIG. The phase lead becomes small, and the step-out phenomenon hardly occurs. Further, since the cycle of the sinusoidal voltage Eu ′ after the switching of the open loop drive is the same as the cycle T ₀ corresponding to the initial set frequency, the number of rotations of the motor 9 is changed after switching from the feedback drive to the open loop drive. It does not drop.

In the present embodiment, the case where the rotation speed in the feedback drive immediately before switching from the feedback drive to the open loop drive is larger than the target rotation speed, but the feedback drive immediately before the switch from the feedback drive to the open loop drive is performed. Motor 9
If the rotation speed is smaller than the target rotation speed, the phase can be delayed during open-loop driving to make it difficult for the step-out to occur.

When the number of rotations at the time of switching from the feedback drive to the open loop drive is high or when the amount of clothes put into the drum 5 is large, the rotor 9
Since the rotational inertia force of b is high, the phase is shifted a little. If the DC voltage supplied to the inverter circuit 57 is low, the phase of the rotor 9b is slow to follow during open loop driving, so that the phase is shifted a little. By setting a plurality of stages, the step-out phenomenon can be more accurately prevented.

Further, by such control, the fixed PWM
Even in a motor with a small output torque in which the phase shift of the rotor 9b with respect to the phase of the sinusoidal voltage supplied to the motor due to the bias of the clothes in the drum 5 during the open loop driving at the duty is suppressed, the phase shift is suppressed. It is difficult to step out. As a result, a motor having a small output torque can be used, and a large motor can be omitted.
Cost reduction can also be achieved.

When the “rinse dehydration operation” is completed, a water supply operation is performed. That is, the drain pump 18 stops,
The water supply valve 13 is opened again. When the water level in the water tank 4 reaches a predetermined level with the opening of the water supply valve 13, the water supply valve 13 is closed. The control device 2 drives the motor 9 based on the rinsing chart. As a result, the drum 5 rotates and the “stirring operation” is performed.

During the "stirring and rinsing operation", a soft finish agent storage box (not shown) and a rinse water supply path communicating with the soft finish agent storage box may be separately provided, and water may be supplied from the rinse water supply route together with the soft finish agent. . Further, the circulation pump 20 is driven during the “washing operation” in the “washing process” or the “stirring operation” in the “rinsing process”, and
The washing liquid inside may be circulated.

When the above “rinse dehydration operation” and “stirring rinse operation” are repeated several times and the “rinse step” is completed, the program recorded in the main control unit 50 is switched to the “dewatering step”. In the “dehydration step”, first, a “draining operation” of closing the water supply valve 13 and operating the drainage pump 18 to drain the washing liquid to the outside is performed.

Then, the control device 2 drives the motor 9 based on the second dehydration chart. As a result, the drum 5 rotates to perform the “finishing dehydration operation”. In the “finish dewatering operation”, the drum 5
The washing liquid is projected to the inner wall of the water tub 4 through the small holes 5a provided on the entire peripheral wall of the tub 4. The protruding washing liquid flows down the inner wall of the water tub 4 to a lower portion, and is drained to the outside through a drain duct 16.
This “finish dewatering operation” is the “rinse dewatering operation” described above.
This is performed in an embodiment similar to the embodiment. However, the settings of the rotation speed and the operation time are different between the two operations.

When the “dehydration step” is completed, the control circuit 2
Controls the motor 9 based on the drying chart to rotate the drum 5 and drives the blower fan 25 and the heater 26 to execute the “drying process”. The air in the drum 5 is supplied to the small hole 5a of the drum 5 and the circulation port 4 of the water tank 4.
c, blower fan 25, heater 26 through cooling duct 27
And circulates into the drum 5 from the suction port 4b.

The air having absorbed the moisture of the laundry in the drum 5 is sucked into the cooling duct 27 by the blower fan 25. The drawn air is cooled by a cooler (not shown) provided in the cooling duct 27 while passing through the cooling duct 27, so that the temperature is lowered. As a result, the air in the cooling duct 27 is dehumidified by the dew condensation of the water, and becomes low humidity air to reach the heater 26.

The air heated by the heater 26 becomes warm air and is blown into the water tub 4 from the outlet 4b, and comes into contact with the laundry again to absorb the moisture of the laundry. Circulating port 4a again
Is sucked into the cooling duct 27, and is similarly cooled and dehumidified by the cooler. By repeating this operation, the “drying step” is performed.

Then, when a predetermined time determined based on the amount of clothing detected from the average value of the phase shift amount δ1 has elapsed, the “drying process” is ended. The water condensed by dehumidification in this “drying step” descends in the cooling duct 27 and is drained to the outside from the inside of the circulation 4 c via the drain duct 16. Incidentally, the end of drying may be detected by a change in temperature or humidity in the outlet 4b or the circulation port 4c of the water tank. In this case, the amount of clothing detected from the phase shift amount is:
It can be used for predicting the operation time before the drying operation and displaying it on the operation panel 11 or the like.

As described above, based on the input from the operation panel 11, the amount of clothing, and the amount of offset of clothing, the controller 2 sets the “washing process”, “rinsing process”, The “dehydration step” and the “drying step” are performed continuously or independently.

In the present embodiment, the present invention is applied to a drum-type inverter washing machine. However, other structures such as a direct-drive inverter washing machine having a pulsator-less structure and an inverter washing machine having a structure in which a motor rotates a pulsator are used. The present invention may be applied to a machine.

[0157]

According to the present invention, the amount of phase shift between the phase of the sinusoidal voltage supplied to the motor and the phase of the rotor position signal detected by the position detecting means at the time of open loop driving during the spin-drying process is determined by the phase shift threshold. If it exceeds, the waveform of the sinusoidal voltage is shifted in a direction to reduce the phase shift amount, so that step-out can be prevented without changing the rotation speed of the motor. Thereby, stable dehydration performance can be obtained. Further, the step-out can be prevented without the need for complicated control as in the prior art and without using a motor having a large output torque. Thereby, cost reduction can be achieved.

Further, according to the present invention, the amount of shift of the sinusoidal voltage waveform is varied in accordance with the change in the amount of phase shift, so that the load torque state and the set number of revolutions of the motor change to change the amount of phase shift. Loss of step can be prevented beforehand. Further, when the phase shift amount is small, it is possible to eliminate a problem that the waveform of the sine wave voltage is shifted too much and a phase shift occurs in the opposite direction.

Further, according to the present invention, the phase shift threshold value is reduced as the commercial power supply voltage is lower. Therefore, when the commercial power supply voltage decreases and the motor output torque decreases, the waveform of the sine wave voltage is shifted earlier. Done. Thus, before the phase shift amount is significantly increased due to a decrease in the motor output torque, the waveform shift of the sine wave voltage is performed, and the phase shift amount can be reduced, thereby preventing step-out beforehand. it can.

Further, according to the present invention, the lower the commercial power supply voltage is, the larger the waveform shift amount of the sine-wave voltage is. Therefore, the phase shift amount is significantly increased due to a decrease in motor output torque accompanying a decrease in the commercial power supply voltage. Even so, the amount of phase shift can be reduced, and loss of synchronism can be prevented.

According to the present invention, the phase shift amount is continuously detected a plurality of times, and the average value of the detected phase shift amounts is compared with the phase shift amount threshold value. Erroneous detection of the rotor position can be prevented, and an accurate phase shift amount can be obtained.

Further, according to the present invention, since the plurality of phase shift amount thresholds are set according to the number of rotations of the motor, the waveform of the sinusoidal voltage can be shifted smoothly. Thereby, intermittent noise and rotation fluctuation during the spin-drying process can be reduced. In addition, since the motor has a characteristic in which an efficient phase shift angle changes according to the number of rotations during open-loop driving, energy saving can be achieved by correcting the phase shift angle to a higher efficiency. You can also plan.

Further, according to the present invention, when the phase shift amount exceeds the phase shift amount threshold value, the set frequency of the sinusoidal voltage is not updated. Temporarily suspend motor acceleration.
This makes it possible to prevent loss of synchronism even with a motor having a small output torque, and cost reduction can be achieved.

Further, according to the present invention, when the phase shift amount does not exceed the phase shift amount threshold continuously for a predetermined period, the set frequency of the sinusoidal voltage can be updated. Motor acceleration is only resumed after it is small and stable. Thereby, reliable acceleration can be performed even if the load torque fluctuates. Further, since a motor having a small output torque can be used, the cost can be reduced.

Further, according to the present invention, when the voltage detected by the voltage detecting means exceeds the threshold value, the waveform of the sine wave voltage is shifted, so that the inverter control means by the back electromotive voltage when the rotor phase advances. Voltage rise can be suppressed. As a result, it is possible to prevent the elements constituting the inverter control means from deteriorating and destructing the withstand voltage, and to use elements having a low withstand voltage, thereby achieving cost reduction.

Further, according to the present invention, the initial phase of the sine-wave voltage in the open loop drive is shifted from the last phase of the sine-wave voltage in the feedback drive. It is possible to prevent the shift amount from increasing. As a result, step-out can be prevented beforehand, and a motor with a small output torque can be used, so that cost reduction can be achieved.

According to the present invention, when switching from feedback drive to open-loop drive, the phase shift amount and the shift direction of the sinusoidal voltage are set to a plurality in accordance with the rotation speed of the motor and the voltage of the inverter control means. Since it is set, even when the rotation speed of the motor or the voltage of the inverter control means is likely to cause step-out, step-out can be prevented beforehand.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a washing machine according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing the washing machine according to the embodiment of the present invention.

FIG. 3 is a side sectional view of another cut surface showing the washing machine in the embodiment of the present invention.

FIG. 4 is a side sectional view of still another cut surface showing the washing machine in the embodiment of the present invention.

FIG. 5 is a chart showing a washing operation of the washing machine in the embodiment of the present invention.

FIG. 6 is a front view showing a suspended state of the washing machine in the embodiment of the present invention.

FIG. 7 is a rear view showing a suspended state of the washing machine in the embodiment of the present invention.

FIG. 8 is a circuit block diagram of a control device of the washing machine according to the embodiment of the present invention.

FIG. 9 is a circuit block diagram of a sub control unit of the washing machine according to the embodiment of the present invention.

FIG. 10 is a diagram showing the characteristics of the average value of the phase shift angle amount with respect to the weight attached to the drum.

FIG. 11 is a diagram illustrating a configuration of a rotor of a motor provided in the washing machine according to the embodiment of the present invention.

FIG. 12 is a diagram illustrating a configuration of a stator of a motor provided in the washing machine according to the embodiment of the present invention.

FIG. 13 is a diagram illustrating a voltage waveform applied to a motor provided in the washing machine and a position signal output from the motor according to the embodiment of the present invention.

FIG. 14 is a diagram illustrating a voltage waveform applied to a motor provided in the washing machine and a position signal output from the motor according to the embodiment of the present invention.

FIG. 15 is a flowchart illustrating the operation of shifting the voltage waveform applied to the motor of the washing machine in the embodiment of the present invention.

FIG. 16 is a diagram showing a motor rotation speed during a dehydration operation.

FIG. 17 is a diagram illustrating a voltage waveform applied to a motor provided in the washing machine and a position signal output from the motor when the operation shifts from feedback driving to open-loop driving.

FIG. 18 is a flowchart illustrating another shifting operation of the voltage waveform applied to the motor of the washing machine in the embodiment of the present invention.

FIG. 19 is a flow chart showing still another shifting operation based on the voltage applied to the motor of the washing machine according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body exterior part 2 Control device 3 Opening / closing door 4 Water tank 4a Opening 4b Outlet 4c Circulation port 5 Drum 5a Small hole 5c Opening 5d Liquid balancer 5e Shaft part 6 Bearing 7a 1st suspension device 7b 2nd suspension device 8a, 8b Damper 9 Motor 9a Motor case 9b Rotor 9c Stator 10 Packing 10a Inner peripheral edge 11 Operation panel 12 Water supply pipe 13 Water supply valve 14 Detergent case 15 Water supply nozzle 16 Drain duct 17 Connection case 17a Filament filter 18 Drain pump 19 Circulation duct 20 Circulation pump 21 Dynamic pressure pipe 22 Air trap 23 Water level sensor 24 Drying unit 25 Blower fan 26 Heater 27 Cooling duct 28 Buffer material 29a, 29b Angle 30a, 30b Angle 50 Main control unit 51 Sub-control unit 52 Buzzer 53 Commercial power 54 Reactor 55 Rectifier circuit 56a, 56b Capacitor 57 Inverter circuit 58a-59c Transistor 59a-59c Transistor 60a-60c Diode 61a-61c Diode 62 Drive circuit 63a-63c Hall sensor 64 Microcomputer 65 Inverter input voltage detecting means 71 Rotor core 71A Rotor core Salient pole portion 71N Salient pole portion of rotor core which is N pole 71S Salient pole portion of rotor core which is S pole 72 Permanent magnet 72N N pole portion of permanent magnet 72S S pole portion of permanent magnet 73 Stator core 74 Winding Hu, Hv, Hw Rotor position signal P1 to P6 Drive signal

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3B155 BA11 BA23 BB15 KA36 KB08 KB11 LA02 LB21 LC13 LC15 LC33 MA01 MA02 MA05 MA06 MA07 MA09 5H560 AA10 BB04 BB07 BB12 DA02 DA19 EB01 EC01 RR05 SS07 TT15 UA02 XA12 5H576 AA12 CC GG06 HA02 HB02 JJ03 LL39 LL41

Claims (11)

[Claims] 1. A control of a washing machine comprising a DC brushless motor for driving a rotating body for washing, an inverter control means for controlling the rotational drive of the motor, and a position detecting means for detecting a rotor position of the motor. In the apparatus, a phase of the sinusoidal voltage that is generated when the motor is supplied with a sinusoidal voltage of a predetermined set frequency during the dehydration step of rotating the washing rotator and centrifugally dehydrating the clothing to perform open loop driving, and While detecting a phase shift amount with respect to the phase of the position signal detected by the position detecting means, if the phase shift amount exceeds a preset phase shift amount threshold, the phase shift amount is reduced in advance. A control device for a washing machine, wherein the waveform of the sine wave voltage is shifted by a set shift amount. 2. The control device for a washing machine according to claim 1, wherein said inverter control means varies said shift amount in accordance with a change in said phase shift amount. 3. The inverter control means includes voltage detection means for detecting at least one of an AC voltage supplied from a commercial AC power supply and a DC voltage obtained by rectifying the AC voltage by rectification means. The lower the voltage detected by
The control device for a washing machine according to claim 1 or 2, wherein the threshold value of the amount of phase shift is reduced. 4. The inverter control means includes voltage detection means for detecting at least one of an AC voltage supplied from a commercial AC power supply and a DC voltage obtained by rectifying the AC voltage by rectification means. The lower the voltage detected by
2. The method according to claim 1, wherein the shift amount is increased.
The control device for a washing machine according to any one of claims 1 to 3. 5. The method according to claim 5, wherein the phase shift amount is detected continuously a plurality of times.
The control device for a washing machine according to any one of claims 1 to 4, wherein the average value of the detected phase shift amounts is compared with the phase shift amount threshold value. 6. The control device for a washing machine according to claim 1, wherein a plurality of the phase shift amount thresholds are set according to the number of rotations of the motor. 7. The washing machine according to claim 1, wherein the set frequency of the sinusoidal voltage is not updated when the phase shift amount exceeds the phase shift amount threshold value. Control device. 8. When the phase shift amount does not exceed the phase shift amount threshold continuously for a preset predetermined period without updating the set frequency of the sinusoidal voltage, the setting of the sinusoidal voltage is performed. The control device for a washing machine according to claim 7, wherein the frequency can be updated. 9. The inverter control means includes voltage detection means for detecting at least one of an AC voltage supplied from a commercial AC power supply and a DC voltage obtained by rectifying the AC voltage by rectification means. When the voltage detected from exceeds a preset voltage threshold, the waveform of the sinusoidal voltage according to the phase shift amount is shifted even if the phase shift amount does not exceed the phase shift amount threshold. Claim 1 to claim
8. The control device for a washing machine according to any one of 8 above. 10. A control of a washing machine comprising a DC brushless motor for driving a rotating body for washing, an inverter control means for controlling the rotational driving of the motor, and a position detecting means for detecting a rotor position of the motor. In the apparatus, during a spin-drying step of spinning the washing rotator and centrifugally spin-drying the clothes, a predetermined set frequency from a feedback drive that supplies a sine-wave voltage synchronized with a position signal from the position detecting means to the motor is provided. When switching to the open-loop drive for supplying a sine-wave voltage to the motor, the initial phase of the sine-wave voltage in the open-loop drive is shifted from the last phase of the sine-wave voltage in the feedback drive. A control device for a washing machine. 11. The inverter control means includes voltage detection means for detecting at least one of an AC voltage supplied from a commercial AC power supply and a DC voltage obtained by rectifying the AC voltage by a rectification means. The shift amount and the shift direction when the initial phase of the sine wave voltage is shifted with respect to the last phase of the sine wave voltage in the feedback drive are the motors used when switching from the feedback drive to the open loop drive. The control device for a washing machine according to claim 10, wherein a plurality of rotation speeds are set according to the number of rotations of the washing machine or the voltage detected by the voltage detection unit.