JP4687583B2 - Washing machine - Google Patents

Description

  The present invention relates to a washing machine having a motor for generating a rotational driving force for rotating a washing tub in order to perform washing, rinsing, dehydration and drying.

  As a conventional washing machine and its motor speed control device, when performing washing, rinsing operation and dehydration operation, a brushless DC motor is used, the brushless DC motor is driven by an inverter circuit, and the voltage applied to the motor is set. Some control the motor torque by increasing or decreasing it.

  The speed control device of the washing machine is constituted by a microcomputer or the like, and includes a PI control unit, a washing speed pattern output unit, a UVW conversion unit, an initial speed pattern output unit, a PWM drive unit, a position speed detection unit, and the like. The PWM signal of each phase output from the PWM drive unit is output to an inverter circuit that drives the motor. A hall sensor is incorporated in the motor to detect the rotational speed of the motor and the position of the rotor. The PI control unit PI-controls the rotation speed of the motor based on the target rotation speed of the dehydration operation output from the operation control unit (not shown) of the washing machine and the detected speed of the motor, and the duty command and the phase command of the PWM signal Is output to the UVW converter.

  The washing speed pattern output unit outputs a duty command and a phase command during the washing operation to the UVW conversion unit. The UVW conversion unit converts a signal output from the PI control unit or the washing speed pattern output unit into a voltage command for each phase of U, V, and W and outputs the voltage command to the PVW driving unit. The initial pattern output unit outputs an energization pattern to the PWM drive unit instead of the UVW conversion unit when the motor is started from a stopped state.

  When performing washing, rinsing operation or dehydration operation, the motor torque is controlled by increasing or decreasing the current applied to the motor in order to suppress noise and vibration by controlling the motor torque with high accuracy. Yes.

  FIG. 17 shows the configuration of a conventional speed control device for a washing machine. The speed control device of the washing machine is composed of a microcomputer or the like, and its functional blocks include a speed command output unit, a speed PI control unit, a current PI control unit, a q-axis and a d-axis as shown in FIG. Dq / αβ conversion unit, αβ / UVW conversion unit, PWM drive unit, AD conversion unit for current detection, αβ / dq conversion unit, UVW / αβ conversion unit, which converts the command value into UVW three-phase output, An estimation unit for estimating the rotation speed is provided. Hereinafter, the first conventional example will be described.

  The speed PI control unit 101 performs PI control based on the difference between the target speed command value and the estimated motor rotation speed that is the output of the speed estimation unit 102, and obtains the q-axis current command value Iqref and the d-axis current command value Idref. Generate and output. Here, the d-axis current in the washing and rinsing operations is set to zero, and the d-axis current at the time of dehydration is set to a predetermined value in order to perform the weakening magnetic field control.

  The actual q-axis current value Iq and d-axis current value Id output from the αβ / dq converter 103 are subtracted by the subtractors 104 and 105, and the difference between the q-axis current command value Iqref and the d-axis current command value Idref is calculated. The calculated current control unit 106 performs PI control based on the difference, generates a q-axis voltage command value Vq and a d-axis voltage command value Vd, and outputs them to the dq / αβ conversion unit.

  The dq / αβ conversion unit receives the rotor phase angle detected by the estimation unit, and converts the voltage command values Vd and Vq based on the rotation phase angle to Vα and Vβ, and outputs them.

  The voltage command values Vα and Vβ are input to the αβ / UVW conversion unit, converted into three-phase voltage command values Vu, Vv, and Vw, and input to the PWM forming unit.

  The PWM forming unit outputs a PWM signal of each phase obtained by modulating a carrier wave of 16 kHz based on a voltage command value of three phases to an inverter circuit, so that a sine wave current is passed through each phase of the motor. A signal having a pulse width with respect to a voltage amplitude based on the above is output (for example, see Patent Document 1).

  Further, as another second conventional motor control device, as shown in FIG. 18, the motor control signal is created by energizing / disconnecting the motor drive signal by the current control process 201 and the PWM process 202, and the motor is stopped. The energization pattern of the immediately preceding motor drive signal is learned by the pattern learning process 203, and when it is restarted, it is created by the pattern calculation process 204 based on this learned pattern, so that the motor drive current can be matched with the command value at an early stage. Some have reduced vibration and noise (for example, see Patent Document 2).

  Further, as another third conventional motor control device, vibration and noise are controlled by driving the motor while switching between control driving using a rotor position signal synchronized with motor rotation and asynchronous control driving. Some have been suppressed (see, for example, Patent Document 3).

FIG. 19 shows the configuration of a control device for a third conventional inverter washing machine. The inverter washing machine is driven by detecting the rotational position of the motor 301 with the DC brushless motor 301 by the rotor position detecting means, and the inverter means built in the sub-control unit 302 supplies a three-phase current to the motor 301. The sub-control unit 302 activates the motor with a signal synchronized with the rotor position signal when the motor 301 is activated. When the rotational speed of the motor reaches a predetermined value A, the motor is driven by a predetermined signal that is asynchronous with the rotor position signal. As a result, the motor can be driven by a signal that does not depend on the mounting position of the rotor position detecting means, so that vibration and noise of the motor are suppressed.
JP 2003-53092 A JP-A-7-264890 JP 2000-224890 A

  The washing machine rotates the washing tub at high speed with a motor in the dehydration process. Due to the high-speed rotation, the motor control system causes a large current to flow through the motor, and there is a problem that noise due to cogging vibration or torque ripple vibration is generated.

  Torque ripple is 6n times the motor control fundamental frequency (n is an integer of 1 or more), and when the 8-pole motor is rotated at 900 r / min, the primary component is 360 Hz and the secondary component is 720 Hz. The cogging torque is the least common multiple of the number of motor poles and the number of coils (slots). In the case of an 8-pole 12-slot motor, it is 24 k times the motor rotation speed (k is an integer of 1 or more), and the motor is 900 r / min. , The primary component becomes 360 Hz and the secondary component, and these vibrations generate not only a motor but also a housing and a washing tub, resulting in a loud noise.

  In the first conventional configuration, the torque of the motor is controlled only by a voltage command as shown in FIG. Although current is proportional to torque, there is a delay in the drive circuit, and there is a delay in the transfer function from voltage to torque. Therefore, the control operation is also delayed, and accurate speed control cannot be performed even in the absence of disturbance. . Increasing the control band of the speed control to 1 kHz so that the above-described vibration can be compensated is not practical for reasons such as sensor noise and motor time constant. Therefore, vibration disturbances such as the cogging torque and torque ripple are not compensated by the control system, and there is a problem that vibration and noise are generated in the washing machine dehydration process.

  In the second conventional configuration, the torque of the motor is controlled by a current command as shown in FIG. Since the current is proportional to the torque, the current is feedback-controlled even if there is a delay in the drive circuit, so that the delay in operation can be reduced, and accurate speed control and torque control are possible.

  However, if there is a vibration disturbance such as the cogging torque or torque ripple, even if the speed change due to the disturbance can be detected, it is only possible to reduce the speed fluctuation only with the compensation gain determined by the control band with the speed feedback alone. It is. Although DC low-frequency disturbances can be compensated, accurate compensation cannot be made for AC disturbances (especially above the control band), resulting in speed fluctuations, and hence vibration and noise caused by speed fluctuations. Had problems.

  Further, in the third conventional configuration, as shown in FIG. 19, the learning processing unit is used to make the motor drive current coincide with the command value at an early stage.

  However, the learning processing unit learns the previous energization time and reflects the pattern next time, and does not have a function of learning and compensating for the control drive current for cogging vibration or torque ripple vibration.

  Therefore, vibration disturbances such as cogging torque and torque ripple are not compensated by the control system, and there is a problem that vibration and noise are generated in the washing machine dehydration process.

  In the third conventional configuration, as shown in FIG. 19, a method of controlling the motor by using a rotation synchronization signal such as a Hall element and a method of controlling the motor asynchronously without using it are switched. Thus, a configuration is adopted in which vibration and noise due to the motor are reduced by reducing energization error due to mounting position error of the Hall element, distortion of the driving current, and torque ripple caused thereby.

  However, torque ripple is a vibration that is generated in principle when a three-phase motor is controlled by sinusoidal drive, and the cogging torque vibration is the number of poles, although there is a large or small difference in the case of a synchronous rotating machine such as a brushless motor. And vibration generated by magnetic excitation synchronized with the rotation determined by the least common multiple of the number of coils.

  Therefore, when the rotation of the three-phase motor is controlled using the asynchronous sine wave signal, the vibration disturbance as described above is not compensated, and there is a problem that vibration and noise are generated in the dehydration process of the washing machine. .

  The present invention solves the above-mentioned conventional problems. In order to detect or estimate the cogging vibration and torque ripple vibration of the motor and reduce the vibration, the control signal is a signal for directly canceling the vibration. The vibration generated by the signal is added with a signal having the same amplitude and the opposite phase as the above-described vibration. Actually, cogging vibration is obtained by adding a first order ((N + 1) th order, (N-1) th order) signal of the motor control fundamental frequency N of the vibration in question to the control signal and performing feedforward compensation. Or cancel the torque ripple vibration.

  Accordingly, it is an object of the present invention to provide a washing machine capable of preventing vibration and noise caused by motor rotation even when a large current flows at high speed in the dehydration process of the washing machine.

  In order to solve the conventional problems, a washing machine of the present invention includes a washing tub for rotating laundry, a motor for rotating the washing tub, speed detection means for detecting the rotation speed of the washing tub, Current detecting means for detecting current flowing in the motor, control means for controlling the motor based on the detected speed, current and target value, vibration detecting means for detecting vibration due to torque ripple and cogging torque, and for canceling vibration Vibration control means for adding a vibration control amount to the control means, the control means performing a vector control based on the detected current to calculate a torque control amount and adding the torque control amount and the vibration control amount. In addition to having a wave vibration adder, the vibration adder has addition switching means for switching whether or not to add a vibration control amount in accordance with the operation mode of the washing machine.

  As a result, even when a large current flows at a high speed in the washing machine dehydration process, the cogging torque vibration, torque ripple vibration and noise caused by the motor rotation are estimated and detected as the vibration. It can be reduced or prevented by feedforward control.

  The washing machine of the present invention can reduce and prevent cogging torque vibration, torque ripple vibration, and noise caused by the vibration even when a large current flows at high speed in the dehydrating process of the washing machine.

  According to a first aspect of the present invention, there is provided a washing tub for rotating the laundry, a motor for rotationally driving the laundry tub, speed detection means for detecting the rotation speed of the laundry tub, and current detection means for detecting a current flowing through the motor. Control means for controlling the motor based on the detected speed, current and target value; vibration detection means for detecting vibration due to torque ripple and cogging torque; and vibration control for adding a vibration control amount for canceling vibration to the control means. The control means includes a harmonic vibration adder for calculating a torque control amount by performing vector control based on the detected current and adding the torque control amount and the vibration control amount, and adding the vibration addition The machine has an addition switching means for switching whether or not to add the vibration control amount according to the operation mode of the washing machine. Even when a large current, cogging torque vibration motor rotation is caused, the torque ripple vibration and noise caused thereby, the estimated or detected vibration, reduction in the feed forward control can be prevented.

  In the second invention, in particular, the control means of the first invention has current error detection means for calculating a current error between the target value of the current and the actual value, and the vibration detection means By estimating the amplitude and phase, it is possible to estimate the amplitude and phase of the vibration with high accuracy, and the motor rotation is caused even when a large current flows at high speed in the washing machine dehydration process. The cogging torque vibration, torque ripple vibration and noise caused thereby can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  In the third aspect of the invention, in particular, the control means of the first aspect of the invention has speed error detection means for calculating a speed error between the target value of the speed and the actual value. By estimating the amplitude and phase, it is possible to estimate the amplitude and phase of the vibration with high accuracy, and the motor rotation is caused even when a large current flows at high speed in the washing machine dehydration process. The cogging torque vibration, torque ripple vibration and noise caused thereby can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  In the fourth invention, in particular, the vibration detecting means of the first invention is an acceleration sensor, and by detecting the vibration of the motor, the high-frequency vibration generated by the motor can be detected with high accuracy in a small size. In the dehydration process of the washing machine, even when a large current flows at a high speed, the cogging torque vibration, torque ripple vibration and noise caused by the motor rotation are estimated or detected by the vibration. It can be reduced or prevented by feedforward control.

  According to a fifth aspect of the invention, in particular, the vibration control means of any one of the first to fourth aspects of the invention is configured to attenuate the motor current fundamental frequency N times or N-1 of the motor current fundamental frequency in order to attenuate the vibration of N times the motor current fundamental frequency. Output to the control means, it is possible to actively cancel the Nth order vibration generated by the motor, and in the dehydration process of the washing machine, a large current flows at a high speed. However, cogging torque vibration, torque ripple vibration and noise caused by the motor rotation can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  In particular, the sixth aspect of the invention provides the vibration control means of the fifth aspect of the invention, and outputs to the control means a frequency signal of an order of (integer multiple of 6 + 1) or (integer multiple of −1) of the motor phase current fundamental frequency. Therefore, it is possible to positively cancel the torque ripple vibration generated by the motor control, and the cogging torque caused by the motor rotation even when a large current flows at a high speed rotation in the washing machine dehydration process. Vibration, torque ripple vibration, and noise caused thereby can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  According to a seventh aspect of the invention, in particular, the vibration control means of the fifth invention outputs a frequency signal of the order of (integer multiple +1) or (integer multiple -1) of the motor cogging vibration frequency to the control means. Cogging vibration generated by the control can be positively canceled, and even when a large current flows at high speed in the dehydration process of the washing machine, cogging torque vibration and torque ripple vibration caused by motor rotation And the noise caused thereby can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  In the eighth invention, in particular, the harmonic vibration adder according to any one of the first to seventh inventions determines whether or not to add the vibration control amount according to the magnitude of the motor current or the motor rotation speed. By having an addition switching means for switching, harmonic vibration can be applied only in the case of a rotational speed at which noise due to motor vibration is generated, and in a dehydration process of a washing machine, a large current is passed at high speed. However, cogging torque vibration, torque ripple vibration and noise caused by the motor rotation can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  In the ninth aspect of the invention, in particular, the harmonic vibration adder of the eighth aspect of the present invention adds a vibration control amount to a d-axis control signal and a q-axis control signal, which are two-phase signals for vector control calculation. It is possible to add harmonic vibration for canceling motor vibration to the system, and in the dehydration process of the washing machine, even when high current flows at high speed, cogging torque vibration caused by motor rotation, Torque ripple vibration and noise caused thereby can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  In the tenth aspect of the invention, in particular, the harmonic vibration adder of the eighth aspect of the invention is a three-phase signal that outputs a control amount to the motor. The U-phase control signal, the V-phase control signal, and the W-phase control signal are vibration control amounts. It is possible to add harmonic vibration for motor vibration cancellation to a three-phase motor, and even if a large current is passed at high speed in the dehydration process of the washing machine, the motor rotation Cogging torque vibration, torque ripple vibration and noise caused by the above can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  In the eleventh aspect of the invention, in particular, the control means of the first or eighth aspect of the invention has gain adjusting means for adjusting the control gain in accordance with the operation of the addition switching means, so that a control signal by adding a harmonic vibration control amount is provided. In the dehydration process of the washing machine, even when a large current flows at high speed, the cogging torque vibration, torque ripple vibration and noise caused by the motor rotation are reduced. It can be reduced or prevented by estimating or detecting the vibration and feedforward control.

  In the twelfth aspect of the invention, in particular, the control means of the first or eighth aspect of the invention has control system switching means for changing the feedback control method in accordance with the operation of the addition switching means, thereby adding a harmonic vibration control amount. It is possible to prevent deterioration of control performance, and in the dehydration process of the washing machine, even when a large current flows at a high speed, the cogging torque vibration, torque ripple vibration and noise caused by the motor rotation are reduced. The vibration can be reduced or prevented by estimation or detection of the vibration and feedforward control.

  In the thirteenth invention, in particular, the vibration control means of any one of the first to twelfth inventions has a basic vibration control amount for correcting cogging vibration in the memory as a map, and motor current or motor rotation speed. Alternatively, by having a vibration adjusting means that outputs the vibration control amount by adjusting the amplitude and phase according to the control band, it becomes possible to output the harmonic vibration control amount according to the rotation speed, and the dehydration of the washing machine In the process, even when a large current flows at high speed, the cogging torque vibration, torque ripple vibration and noise caused by the motor rotation are reduced by estimation or detection of the vibration and feedforward control. Can be prevented.

  In the fourteenth aspect of the invention, in particular, the motor of any of the first to thirteenth aspects of the invention is a three-phase DC synchronous rotating machine, so that a harmonic vibration control amount can be added to the three-phase control signal. It is possible to estimate or detect the cogging torque vibration, torque ripple vibration and noise caused by the motor rotation, even if a large current flows at high speed in the washing machine dewatering process. This can be reduced or prevented by feedforward control.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1)
FIG. 1 is a block diagram of a motor control device for a washing machine according to the first embodiment of the present invention. In FIG. 1, 10 is a washing machine mechanism, 11 is a rotating drum of a washing tub for rotating laundry, 12 is a brushless motor for rotating the rotating drum while controlling the speed, and 13 is a washing tub for storing laundry and water. A water receiving cylinder, 18 is a cover having a laundry loading opening, 14 is a window packing for connecting the washing tub and the cover having the laundry loading window without a gap, and 15 is for supporting the posture of the washing tub 11. 16 is a damper for reducing vibration generated during washing (during motor rotation) to reduce vibration transmission to the cover 18 and the floor, 17 is a lid for the laundry inlet, and 19 is a washing machine. Anti-vibration rubber installed on the floor.

  Here, the motor 12 is a brushless motor having 8 poles and 12 coils. Also, 100 is a washing machine electrical section, 30 is a speed detecting means for detecting the rotational speed Vm of the motor 12, 21 is a difference between the rotational speed command value Vref and the detected actual rotational speed Vm, and outputs a speed deviation VE. A speed error subtractor, 22 is a speed control means for calculating and outputting the control amount Ia based on the speed deviation VE, 40 is a current detection means for detecting the motor drive current Im, and 20 is a control means for controlling and driving the motor. , 23 is a current error subtractor that outputs a difference between the control amount Ia and the detected motor drive current Im, 24 is a current control means that outputs a current control amount for feedback control of the current by vector control, and 25 is a two-phase d Control command means for converting the shaft current and q-axis current into U-phase, V-phase, and W-phase three-phase currents that are actually applied to the three-phase brushless motor and outputting the current to the motor by PWM control. A driving means of the inverter circuit added.

  Further, 50 is a vibration detecting means for detecting cogging vibration from the current error, 51 is estimating or detecting the amplitude and phase of the detected harmonic vibration, and a harmonic vibration control amount that cancels the harmonic vibration. The vibration control means 27 that calculates and outputs, 27 is a harmonic vibration adder that adds the vibration control quantity to the current control quantity, and 28 is a harmonic that is the vibration control quantity that the vibration control means 51 outputs according to the operation mode of the washing machine. Addition switching means for controlling whether or not the harmonic current is added to the current control amount by controlling the wave current.

  FIG. 2 is a detailed block diagram of the motor control device for the washing machine according to the first embodiment of the present invention. Hereinafter, a control method based on vector control will be described. The target rotational speed of the motor is commanded from a washing machine controller (not shown here). The motor used here is a brushless DC motor, and among them, a reluctance motor that is rotated by using a reluctance torque. In the figure, reference numeral 12 denotes a brushless motor, 12-1 denotes a motor unit composed of a magnet and a coil, and 12-2 denotes a hall element capable of detecting the rotor phase.

  Here, the speed detecting means 30 uses a tachometer. The brushless tacho generator is composed of a hall element, a comparator, and an analog switch incorporated in the motor. The speed detection means 30 detects the rotational speed Vm of the motor.

  The subtracter 21 outputs the target rotational speed Vref and the detected speed deviation VE of the motor rotational speed Vm, and the speed control means 22 calculates the control amount Ic based on the speed deviation VE. FIG. 3 shows a block diagram of the speed control means 22. The speed control means multiplies the speed deviation VE by the speed feedback gain Kv to calculate the speed feedback control amount Uv, and multiplies the integral value of the speed deviation VE by the integral feedback gain to calculate the integral feedback control amount Ui. The two control amounts are added by the adder 22-4, and the control amount Ia is output.

  The control amount Ia in FIG. 1 is the q-axis (quadrature) current command Iqa in the vector control of the brushless motor in FIG. In FIG. 2, a d (direct) shaft current command Ida corresponding to the reluctance torque is output from the washing machine controller according to the target rotational speed.

  Next, the current control means 24 will be described. In the three-phase UVW / dq converter 24-8 in FIG. 2, the q-axis current Iq and the d-axis current Id are detected from the U-phase current and the V-phase current. FIG. 3 shows a block diagram of the current control means 24, and FIG. 4 shows a block diagram of a three-phase UVW / dq converter. Subtractors 24-1 and 24-2 calculate a deviation Iqa 'from the q-axis command current and a deviation Ida' from the d-axis command current from the current value. Then, proportional integration control (PI control) is performed on each deviation in the same manner as the speed control means 22, and command voltages Vqa and Vda are output.

  FIG. 5 shows a block diagram of the non-interference controller. Here, Φ is the number of phase armature flux linkages, and La is the self-inductance of the armature winding. The command voltages Vqa and Vda thus calculated are added to the command voltages Vqa 'and Vda' which are independent from each other by adding the outputs of the non-interference controller 24-7 by the adders 24-5 and 24-6. The brushless motor has a speed electromotive force that interferes between the d and q axes. They affect the q-axis current Iq and the d-axis current Id, but cannot be directly controlled. Therefore, the non-interference controller 24-7 here is a control that obtains the speed electromotive force and cancels them. In the non-linear controller, the non-linear control amount is calculated from the armature winding self-inductance La and the number of winding linkage magnetic fluxes Φ. The normal torque constant kt is determined by the number of poles p and Φ. The mutually independent command voltages Vqa ′ and Vda ′ are output to the dq / 3-phase UVW converter of the control command means 25.

  FIG. 6 shows a book diagram showing the relationship between the dq / 3-phase converter 25 and the rotor phase angle calculator 26-4. The dq / 3-phase converter 25 multiplies the command voltages Vqa ′ and Vda ′ by the sine value and cosine value of the rotor phase angle to give command voltages Vu to three phases (U phase, V phase, W phase), Vv and Vw are output to the PWM inverter circuit 26-2. The PWM inverter circuit 26-2 outputs a pulse wave signal having a carrier frequency of 15.6 kHz and an applied voltage of 100 V to the brushless motor 12 with respect to the three-phase sine wave command voltage. A current detector 26-3 is a resistor, and the detected U-phase and V-phase current values are output to the three-phase UVW / dq converter 24-8.

  Next, the principle of attenuating cogging vibration and torque ripple vibration by harmonic vibration due to harmonic current will be described.

  In the case of a three-phase motor, torque ripple is generated at a frequency that is 6n times (n is an integer of 1 or more). Further, the cogging torque is generated at mk times (m is an integer of 1 or more) of the motor rotation number at the least common multiple k of the number of poles of the rotor magnet and the number of stator coils. In this embodiment, the cogging torque is 6n times the motor fundamental frequency. Occurs at frequency.

  In general, a magnetic excitation force applied to motor driving is generated by a rotor magnetomotive force and a stator current. Further, in order to attenuate the harmonic vibration of the order 6n, a magnetic excitation force having an amplitude and a phase that reduce the amplitude of the vector sum with the harmonic vibration may be added. It has been found that this magnetic excitation force can be achieved by superimposing a harmonic current on the stator that is one larger or smaller than the order of the harmonic vibration to be damped.

It is known that the 6th and 12th harmonic vibrations are generated by the following rotor magnetomotive force and stator current.
The 6th rotor magnetomotive force of the 6th rotor magnetomotive force due to the 3rd harmonic component of the rotor magnetomotive force and the 6th rotor magnetomotive force of the 6th rotor magnetomotive force due to the 5th harmonic component and the 6th rotor magnetomotive force due to the 7th harmonic component 6th order by the 5th harmonic component of the 12th rotor magnetomotive force due to the second harmonic component and the 7th harmonic component of the 6th rotor magnetomotive force by the primary component of the stator current and the primary component of the stator current. In the motor controller, the 6th and 12th harmonic vibrations cause noise, and the 6th and 12th orders are attenuated by adding the 7th and 13th harmonic current components to the stator current. It is possible to generate harmonic vibrations.

In the following, harmonic vibrations generated by superposition of the 7th and 13th components of the stator current are listed.
6th component generated by the rotor magnetomotive force primary component and the stator current 7th component 12th component generated by the rotor magnetomotive force primary component and the stator current 13th component and the rotor current magnetomotive force 5th component and the stator current 7th component 12th-order component rotor magnetomotive force 5th-order component and stator current 13th-order component generated 18th-order component rotor magnetomotive force 7th-order component and stator current 13th-order component generated 6th-order component stator current primary component and 7th-order component 6th-order component stator current generated 12th-order component stator current generated by the 13th-order component and 6th-order component generated by the 13th-order component. The 6th and 12th harmonic vibrations, which are vibrations, are generated by superimposing the 7th and 13th harmonic current components on the stator current. Can be attenuated.

  Next, feedforward control of harmonic vibration by harmonic current using the above principle will be described.

  The vibration detection means 50 estimates the amplitude and phase of cogging vibration from the current error. Since the motor has 8 poles and 12 coils, the cogging vibration is the primary component of the 24th order of the motor speed and the 6th order of the motor fundamental frequency. The vibration detection means stores the fundamental waves of the motor fundamental frequency 6th and 12th components in the memory in advance, and compares them with the output of the current error subtractor 23 to estimate and output the amplitude and phase.

  The vibration control means 51 has a 7 (6 + 1) order component for the 6th order vibration, a 13 (12 + 1) order component for the 12th order, and a 6th order component based on the amplitude and phase output from the vibration detecting means. , Output harmonic current signals for harmonic vibration of the same amplitude and opposite phase so as to cancel the 12 components.

  The harmonic current signal is added to vqa ′ and vda ′ by the adder 27. Further, the vibration addition switching means 28 limits the output of the harmonic current in accordance with the washing mode that is the output from the washing machine controller.

  For example, the harmonic vibration is output in the dehydration mode in which the motor is rotated at a high speed rotation of 800 r / min, and is not output in the other modes.

  The above is the signal flow and control algorithm of the brushless motor control system including the harmonic vibration compensation by the harmonic current.

  The experimental results of noise and drive current with the following specifications are shown in FIGS. FIG. 7 shows the case without harmonic vibration control, and FIG. 8 shows the case with harmonics, where (a) shows motor noise and (b) shows motor control current.

From the experimental results of FIG. 7 and FIG. 8, in the case of the harmonic vibration control from the FFT result of the motor noise, there is a 16 dB attenuation in the 12th-order component. In addition, it can be confirmed that the 13th-order component is added to the FFT result of the control current when the harmonic vibration control is performed.
<Experimental specifications>
Motor torque constant: 0.83 Nm / A
Inertia of washing tub: 2.25 × 10 ^ 4 kgm ^ 2
Target rotational speed: 800 to 900 r / min
Sampling frequency: 3 kHz
d-axis current: 2.5A
Control bandwidth: 45
Inverter carrier frequency: 15.6 kHz
Order of added harmonic current: 13th order As described above, a harmonic vibration signal can be added to the motor control signal, cogging vibration can be attenuated, and vibration and noise can be prevented.

  In the present embodiment, the motor torque constant, the inertia of the washing tub and the motor, the target speed, the sampling frequency, the carrier frequency, and the control band are set as the above specifications, but the same effect can be obtained with other specifications. It is.

(Embodiment 2)
FIG. 9 is a block diagram of a motor control device for a washing machine according to the second embodiment of the present invention. Since the basic configuration of the speed control device is the same as that of the first embodiment, the basic description is omitted here. Further, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG.

  The difference from FIG. 1 is that the vibration detecting means 50 detects cogging vibration from the speed error, and the harmonic vibration adder 27 that adds the harmonic current to the current control amount is the output of the control command means 25. The harmonic voltage signal of the harmonic vibration component is added to the three-phase voltage signal.

  That is, the cogging vibration is detected from the harmonic vibration included in the speed deviation, and the harmonic voltage signal for generating the thirteenth harmonic vibration is added to the command voltage signal to the driving means that is an inverter circuit including the PWM control circuit. Thus, the 12th-order component which is a problem is attenuated.

  As described above, the harmonic vibration signal can be added to the motor control signal, the cogging vibration can be attenuated, and vibration and noise can be prevented.

(Embodiment 3)
FIG. 10 is a block diagram of a motor control device for a washing machine according to the third embodiment of the present invention. Since the basic configuration of the speed control device is the same as that of the first embodiment, the basic description is omitted here. Further, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG.

  The difference from FIG. 1 is that the vibration detection means 50 detects the cogging vibration from the vibration sensor of the piezoelectric element arranged in the motor, and the harmonic vibration that adds the harmonic current to the current control amount. The adder 27 is adding the harmonic voltage signal of the harmonic vibration component to the three-phase voltage signal that is the output of the control command means 25.

  That is, the cogging vibration is detected from the harmonic vibration included in the speed deviation, and the harmonic voltage signal for generating the thirteenth harmonic vibration is added to the command voltage signal to the driving means that is an inverter circuit including the PWM control circuit. Thus, the 12th-order component which is a problem is attenuated.

  As described above, the harmonic vibration signal can be added to the motor control signal, the cogging vibration can be attenuated, and vibration and noise can be prevented.

(Embodiment 4)
FIG. 11 is a block diagram of a motor control device for a washing machine according to the fourth embodiment of the present invention. Since the basic configuration of the speed control device is the same as that of the first embodiment, the basic description is omitted here. Further, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG.

  The difference from FIG. 1 is that the addition switching means 28 does not respond to the washing operation mode, but the vibration control means 51 adds the harmonic current signal for generating the harmonic vibration according to the detected motor drive current value. Whether or not to output to the device 27 is being controlled.

  That is, for example, when a current of 1 A or more flows in accordance with the motor drive current, by adding a harmonic current signal for generating a 13th harmonic vibration to the current control amount and outputting it to the control command means The 12th order component which is a problem is attenuated. When the amount of laundry is large, the motor drive current is increased, thereby preventing the noise caused by cogging vibration from increasing.

  As described above, the harmonic vibration signal can be added to the motor control signal, the cogging vibration can be attenuated, and vibration and noise can be prevented.

(Embodiment 5)
FIG. 12 is a block diagram of a motor control device for a washing machine according to a fifth embodiment of the present invention. Since the basic configuration of the speed control device is the same as that of the first embodiment, the basic description is omitted here. Further, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG.

  The difference from FIG. 1 is that the addition switching means 28 does not depend on the washing operation mode, but the vibration control means 51 adds the harmonic current signal for generating the harmonic vibration according to the detected value of the motor rotation speed. Whether or not to output to the device 27 is being controlled.

  That is, according to the motor rotation speed, for example, when rotating at a rotation speed of 300 r / min or more, a harmonic current signal that generates 13th harmonic vibration is added to the current control amount to the control command means. By outputting, the 12th order component which is a problem is attenuated. When the laundry starts dehydrating, the noise caused by cogging vibration is prevented from increasing as the rotational speed increases.

  As described above, the harmonic vibration signal can be added to the motor control signal, the cogging vibration can be attenuated, and vibration and noise can be prevented.

(Embodiment 6)
FIG. 13 is a block diagram of a motor control device for a washing machine according to a sixth embodiment of the present invention. Since the basic configuration of the speed control device is the same as that of the first embodiment, the basic description is omitted here. Further, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG.

  A difference from FIG. 1 is that a gain adjusting means 60 is provided. The gain adjusting means 60 changes the control gains of the speed control means 22 and the current control means 24, Kv and Ki in FIG. 3, according to the control of the harmonic current signal by the addition switching means 28.

  When the rotational speed is increased in the dehydration mode and no harmonic current signal is added, the motor control is performed with the control band for speed control being 20 Hz and the control band for current control being 100 Hz. After the rotation speed reaches the predetermined rotation speed 900 r / min in the dehydration mode, the harmonic current is added by the addition switching means 28 and the vibration control means 51. In accordance with the addition of the harmonic current, the gain adjusting means 60 adjusts the control gain so that the current control band is 400 Hz. As a result, the harmonic current is added with high sensitivity.

  That is, by adjusting the control band according to the washing mode and the motor rotation speed, adding a harmonic current signal for generating 13th harmonic vibration to the current control amount and outputting it to the control command means The 12th order component is attenuated. When the laundry starts dehydrating, the noise caused by cogging vibration is prevented from increasing as the rotational speed increases.

  As described above, the harmonic vibration signal can be added to the motor control signal, the cogging vibration can be attenuated, and vibration and noise can be prevented.

(Embodiment 7)
FIG. 14 is a block diagram of a motor control device for a washing machine according to a seventh embodiment of the present invention. Since the basic configuration of the speed control device is the same as that of the first embodiment, the basic description is omitted here. Further, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG.

  A difference from FIG. 1 is that a control system switching means 70 is provided. The control method switching means 70 disconnects the feedback loop between the speed control means 22 and the current control means 24 in accordance with the control of the harmonic current signal by the addition switching means 28.

  When the rotational speed is increased in the dehydration mode and no harmonic current signal is added, the motor control is performed with the control band for speed control being 20 Hz and the control band for current control being 100 Hz. After the rotation speed reaches the predetermined rotation speed 900 r / min in the dehydration mode, the harmonic current is added by the addition switching means 28 and the vibration control means 51. In accordance with the addition of the harmonic current, the speed control feedback is cut off, and the motor control is performed only by the current control.

  As a result, the harmonic current is added without affecting the speed feedback. The speed feedback is prevented from oscillating due to the speed fluctuation caused by the harmonic vibration.

  That is, by adjusting the control method according to the washing mode and the motor rotation speed, adding a harmonic current signal for generating a 13th-order harmonic vibration to the current control amount and outputting it to the control command means The 12th order component is attenuated. When the laundry starts dehydrating, the noise caused by cogging vibration is prevented from increasing as the rotational speed increases.

  As described above, the harmonic vibration signal can be added to the motor control signal, the cogging vibration can be attenuated, and vibration and noise can be prevented.

(Embodiment 8)
FIG. 15 is a block diagram of a motor control device for a washing machine according to a seventh embodiment of the present invention. Since the basic configuration of the speed control device is the same as that of the first embodiment, the basic description is omitted here. Further, the same components as those in the first embodiment are denoted by the same reference numerals as those in FIG.

  A difference from FIG. 1 is that a motor drive current value is inputted to the vibration control means 51. FIG. 15 shows a detailed block diagram of the vibration control means 51. The vibration control means 51 has harmonic fundamental waves in its internal memory. For example, the fundamental wave of the primary component of cogging vibration at the motor fundamental frequency 6th is stored. With respect to this fundamental wave, the gain determining means 512 determines the amplitude according to the magnitude of the motor current input.

  Next, the phase determining means 513 determines the phase to be delayed based on the phase of the fundamental frequency sixth-order component of the input current error. Based on the output of the addition switching means, the harmonic current signal whose amplitude and phase are determined from the fundamental wave is output to the harmonic current adder 27.

  As a result, even if the motor current is large depending on the amount of laundry, appropriate harmonic vibration can be applied based on the fundamental wave inside.

  In other words, depending on the washing state and motor current, an appropriate harmonic current signal for generating 13th harmonic vibration is added to the current control amount and output to the control command means, so that the twelfth component which is a problem is obtained. It is attenuated. When the laundry starts dehydrating, the noise caused by cogging vibration is prevented from increasing as the rotational speed increases.

  As described above, the harmonic vibration signal can be added to the motor control signal, the cogging vibration can be attenuated, and vibration and noise can be prevented.

  In the first embodiment, the 13th-order component is compensated, but other orders such as 6th-order and 18th-order may be used.

  In the present embodiment, the sensor uses a tachometer and an encoder. However, the same effect can be obtained by using a speed estimation value from another sensor or an observer.

  Further, in the present embodiment, the speed control means is speed feedback control and integral control, but only speed feedback or acceleration feedback may be added.

  In this embodiment, the current control means is proportional control and integral control. However, only proportional control or differential control may be added.

  In the present embodiment, the current feedback control is performed between the speed control and the PWM drive, but may be voltage control.

  Furthermore, although the speed control is used in the present embodiment, the same effect can be obtained even with the positioning control.

  In the present embodiment, the (N + 1) th order 13th harmonic current is added to the 12th order harmonic vibration, but an (N-1) th order 11th harmonic may be added.

  Further, the harmonic signal to be added may be either a harmonic current command or a harmonic voltage command.

  Further, in this embodiment, the phase is adjusted by the detection current or the like, but the harmonics measured in advance may be stored in the memory and the signal may be added as it is.

  In this embodiment, the amplitude is adjusted by a current error or the like, but the harmonics measured in advance may be stored in a memory, and the signal may be added as it is.

  In addition, the added harmonic vibrations only need to have a phase in the range of about 45 degrees with respect to the optimum phase, and the amplitude is in the range of 3 to 1/3 times the optimum amplitude. Just do it.

  The washing machine according to the present invention can reduce and prevent cogging torque vibration, torque ripple vibration and noise caused by it even when a large current flows at high speed in the washing machine dehydration process. It is useful as a motor control device for a washing machine.

1 is a block diagram of a motor control device for a washing machine according to Embodiment 1 of the present invention. Detailed block diagram of motor control device of the washing machine Block diagram of speed control means of the washing machine Block diagram of 3-phase UVW / 2-phase dq converter of the washing machine Block diagram of the non-interference controller of the washing machine Block diagram of 2-phase dq / 3-phase UVW converter of the washing machine (A) FFT diagram of noise as a result of experiment without harmonic vibration control of the washing machine (b) FFT diagram of motor control current as a result of the experiment (A) FFT diagram of noise as a result of experiment with harmonic vibration control of the washing machine (b) FFT diagram of motor control current as a result of the experiment Block diagram of a motor control device for a washing machine in Embodiment 2 of the present invention Block diagram of a motor control device for a washing machine in Embodiment 3 of the present invention Block diagram of a motor control device for a washing machine in Embodiment 4 of the present invention Block diagram of a motor control device for a washing machine in Embodiment 5 of the present invention Block diagram of a motor control device for a washing machine in Embodiment 6 of the present invention Block diagram of a motor control device for a washing machine in Embodiment 7 of the present invention Block diagram of a motor control device for a washing machine in Embodiment 8 of the present invention Detailed block diagram of vibration control means of the washing machine Block diagram of a conventional speed control device for a washing machine Block diagram of another conventional washing machine speed control device Block diagram of a conventional motor control device for a washing machine

Explanation of symbols

11 drums (washing tub)
DESCRIPTION OF SYMBOLS 12 Motor 13 Water receiving cylinder 14 Window packing 15 Support spring 16 Damper 17 Cover 18 Cover 19 Foot rubber 21 Speed error subtractor 22 Speed control means 23 Current error subtractor 24 Current control means 25 Control command means 26 Drive means 27 Vibration adder 28 Addition switching means 20 Control means 30 Speed detection means 40 Current detection means 50 Vibration detection means 51 Vibration control means

Claims (14)

A washing tub for rotating laundry, a motor for rotating the washing tub, a speed detection means for detecting the rotation speed of the washing tub, a current detection means for detecting a current flowing through the motor, and the detected speed and current Control means for controlling the motor from the target value, vibration detection means for detecting vibration due to torque ripple and cogging torque, and vibration control means for adding a vibration control amount for canceling vibration to the control means, The control means includes a harmonic vibration adder that calculates a torque control amount by performing vector control based on the detected current and adds the torque control amount and the vibration control amount, and the vibration adder includes a washing machine A washing machine comprising addition switching means for switching whether or not to add a vibration control amount according to an operation mode. The control means includes current error detection means for calculating a current error between a target value and an actual value of the current, and the vibration detection means estimates the amplitude and phase of vibration from the current error. 1. The washing machine according to 1. The control means includes speed error detection means for calculating a speed error between a target value of the speed and an actual value, and the vibration detection means estimates the amplitude and phase of vibration from the speed error. 1. The washing machine according to 1. The washing machine according to claim 1, wherein the vibration detection means is an acceleration sensor and detects vibration of the motor. 2. The vibration control means outputs a frequency signal of order N + 1 or N−1 of the motor current fundamental frequency to the control means in order to attenuate a vibration N times the motor current fundamental frequency. The washing machine of any one of -4. 6. The washing machine according to claim 5, wherein the vibration control means outputs a frequency signal of an order of (integer multiple of 6 + 1) or (integer multiple of -1) of the motor phase current fundamental frequency to the control means. 6. The washing machine according to claim 5, wherein the vibration control means outputs a frequency signal having an order of (integer multiple + 1) or (integer multiple-1) of the motor cogging vibration frequency to the control means. 8. The harmonic vibration adder includes addition switching means for switching whether to add a vibration control amount according to the magnitude of the motor current or the motor rotation speed. The washing machine according to item. 9. The washing machine according to claim 8, wherein the harmonic vibration adder adds a vibration control amount to a d-axis control signal and a q-axis control signal which are two-phase signals subjected to vector control calculation. 9. The harmonic vibration adder adds a vibration control amount to a U-phase control signal, a V-phase control signal, and a W-phase control signal, which are three-phase signals for outputting a control amount to a motor. Washing machine. The washing machine according to claim 1 or 8, wherein the control means includes gain adjustment means for adjusting a control gain in accordance with an operation of the addition switching means. 9. The washing machine according to claim 1, wherein the control means includes a control system switching means for changing a feedback control method in accordance with an operation of the addition switching means. The vibration control means has a basic vibration control amount for correcting cogging vibration inside the memory as a map, and outputs the vibration control amount by adjusting the amplitude and phase according to the motor current, motor rotation speed or control band The washing machine according to any one of claims 1 to 12, further comprising vibration adjusting means. The washing machine according to any one of claims 1 to 13, wherein the motor is a three-phase DC synchronous rotating machine.