KR20150055466A - Laundry treating apparatus and control method of the same - Google Patents

Abstract

The present invention relates to a control method for a laundry treatment apparatus. The laundry treatment apparatus includes: a rotary drum which stores fabrics; and a motor rotating the drum. The control method includes: an acceleration step of accelerating the drum up to a first speed; a current sensing step of sensing a current applied to the motor while the drum is accelerated to the first speed; a braking step of braking the drum; and a counter electromotive force property value sensing step of sensing the property value of the counter electromotive force corresponding to a change occurring in the counter electromotive force of the motor while braking the drum.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a washing machine,

The present invention relates to a laundry processing apparatus and a control method thereof.

BACKGROUND ART [0002] Generally, a laundry processing apparatus is a device for treating a laundry or a cloth by applying physical and chemical actions to the laundry, a washing machine for removing contamination from the laundry, a dehydrator for spinning the drum containing the laundry at high speed, And a dryer for drying the wet laundry.

Such a laundry processing apparatus senses the amount of bubbles (hereinafter referred to as? Hot water?) Put into the drum before performing the operation such as washing, rinsing, dewatering, and drying, and measures the amount of water, driving course, Time and the like are set.

The detection of the amount of waste is based on the principle that the load applied to the motor is changed according to the amount of the waste, and the value of the current applied to the motor is changed in order to rotate the drum accordingly. Conventionally, the current applied to the motor is measured at every interval in which the drum is accelerated while the acceleration and the stop of the drum are repeated several times, and the amount of the drum is determined based on the measured values. However, this method has a problem that since the load applied to the motor is affected not only by the amount of the battery but also by the state of the battery in the drum, the sensed current values have scattering, there was. Therefore, in order to uniformly disperse the cloth, it is necessary to rotate the drum at a constant speed for a predetermined period of time, or to rotate the drum in order to rearrange the cloth, Such as repetition of acceleration and stop, is required. Therefore, there is a problem in that the time taken until the filling amount is determined becomes long, and as a result, the total time required for the laundry treatment becomes long.

A problem to be solved by the present invention is to provide a laundry processing apparatus and a control method for a laundry processing apparatus, which shortens the detection time and reduces scattering of the obtained collection value.

A control method for a laundry processing apparatus according to the present invention is a control method for a laundry processing apparatus including a drum rotatably provided to receive a can and a motor for rotating the drum, step; A current sensing step of sensing a current applied to the motor while the drum is accelerating at the first speed; A braking step of braking the drum; And a counter electromotive force characteristic value sensing step of sensing a counter electromotive force characteristic value corresponding to a change in the counter electromotive force of the motor while the drum is braked.

A laundry processing apparatus of the present invention includes: a drum rotatably installed to receive a pouch; A motor for rotating the drum; A motor controller for controlling the motor to accelerate and brak down the drum at a first speed; A current sensing unit sensing a current applied to the motor while the motor is accelerating at the first speed; And a counter electromotive force sensing unit for sensing a counter electromotive force characteristic value corresponding to a change in counter electromotive force of the motor while the motor is being controlled so that the drum is braked.

The laundry processing apparatus and the control method of the laundry processing apparatus according to the present invention have the effect of shortening the detection time of the lot.

In addition, the control method of the laundry processing apparatus and the laundry processing apparatus of the present invention has the effect of reducing scattering and obtaining a more accurate coverage value.

1 is a cross-sectional view of a laundry processing apparatus according to an embodiment of the present invention.
2 is a block diagram showing the control relationship between the main components of the laundry processing apparatus of FIG.
3 is a flowchart illustrating a method of controlling a laundry processing apparatus according to an embodiment of the present invention.
FIG. 4 is a graph showing the rotation speed of the drum according to time when the laundry processing apparatus is operated according to the control method according to the embodiment of the present invention.
5 is a view for explaining a current sensing period in a method of controlling a laundry processing apparatus according to an embodiment of the present invention.
6 is a flowchart illustrating a method of controlling a laundry processing apparatus according to another embodiment of the present invention.
FIG. 7 is a graph showing the rotation speed of the drum according to time when the laundry processing apparatus is operated according to the control method according to another embodiment of the present invention.
8 is a view for explaining a current sensing period in the method of controlling a laundry processing apparatus according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

1 is a cross-sectional view of a laundry processing apparatus according to an embodiment of the present invention. 2 is a block diagram showing the control relationship between the main components of the laundry processing apparatus of FIG.

1, a washing machine 100 according to an embodiment of the present invention includes a casing 111 having a filling port, a door 112 for opening and closing the filling port, a tub 112 disposed in the casing 111, A drum 124 rotatably accommodated in the tub 122, a motor 113 rotating the drum 124, and a detergent dispenser 122 accommodating the detergent, (133), and a control panel (114).

A door 112 is rotatably coupled to the cabinet 111 so as to be able to open and close the door. The cabinet 111 is provided with a control panel 114. A detergent box 133 is detachably installed in the cabinet 111.

The tub 122 is disposed in the cabinet 111 so as to be able to be buffered by a spring 115 and a damper 117. The tub 122 receives wash water. The tub 122 is disposed around the drum 124 outside the drum 124.

The motor 113 generates a rotational force for rotating the drum 124. [ The motor 113 is rotatable in a positive direction or in a reverse direction opposite to the positive direction, and may rotate the drum 124 at various speeds or directions.

The drum 124 receives the pod and rotates. The drum 124 is disposed inside the tub 122. The drum 124 is formed into a rotatable cylindrical shape. The drum 124 is formed with a plurality of through holes to allow wash water to pass therethrough. The drum 124 receives the rotational force of the motor 113 and rotates.

The gasket 128 seals between the tub 122 and the cabinet 111. The gasket 128 is disposed between the inlet of the tub 122 and the filling port. The gasket 128 alleviates the shock transmitted to the door 112 when the drum 124 rotates, and at the same time prevents the washing water in the tub 122 from leaking to the outside. The gasket 128 may be provided with a circulation nozzle 127 through which the washing water flows into the drum 124.

The detergent box 133 receives a detergent such as laundry detergent, fabric softener or bleach. The detergent box 133 is preferably detachably provided on the front surface of the cabinet 111. The detergent in the detergent box 133 is mixed with the washing water when the washing water is supplied and flows into the tub 122.

A water supply valve 131 for controlling the inflow of the washing water from the external water source in the cabinet 111, a water supply flow path 132 for flowing the washing water introduced by the water supply valve 131 to the detergent box 133, And a water supply pipe 134 for introducing the washing water mixed with the detergent into the tub 122 is provided in the washing tub 133.

A pump 136 for discharging washing water in the tub, a circulating flow path 137 for circulating the washing water, a circulating flow path 137 for circulating the washing water in the tub 122, A circulation nozzle 127 that flows into the tub 124, and a drain passage 138 through which wash water is drained to the outside. According to the embodiment, the pump 136 may be a circulation pump and a drain pump, and may be connected to the circulation channel 137 and the drainage channel 138, respectively.

The motor 113 includes a stator 113a having a coil wound thereon, a rotor or rotor 113b that generates electromagnetic interaction with the coil and a rotor 113b that detects the position of the rotor 113b And a hall element 113c which is connected to the gate electrode.

2, the laundry processing apparatus may include a motor control unit 230, a PWM operation unit 240, an inverter 250, and a current sensing unit 260. Referring to FIG.

The motor control unit 230 controls the power supplied to the motor 113. The motor control unit 230 may include a position detection unit 231, a speed control unit 233, a current control unit 235, and a coordinate conversion unit 237.

The motor 113 may include a Hall element 113c for detecting the position of the rotor 113b. The Hall element includes an N-type semiconductor, and the intensity of the magnetic field can be measured using a Hall effect. For example, when a current Ih flows through the Hall element and a magnetic flux B is applied to the surface of the element in a direction perpendicular to the current, a voltage Vh proportional to the magnitude of the magnetic flux B is generated in a direction perpendicular to the current Ih and the magnetic flux B do. Since the Hall element can determine the type and size of the poles N and S from the output voltage Vh, it is possible to determine the position of the rotor as a permanent magnet in a PMSM (Brushless DC electric motor) or a BLDC motor Can be detected. Since the Hall element 113c outputs the voltage Vh proportional to the magnitude of the magnetic flux B, it can be used as a current sensor since the magnitude of the current generating the magnetic flux can be known from this.

The position detection unit 231 detects the position of the drum 124 based on the position of the rotor 113b detected by the Hall element 113c. The position detecting section 231 can also detect the rotational speed of the drum 124 based on the detected position of the rotor 113b or the drum 124. [ The position detecting unit 231 can detect the rotational speed of the motor 113 through the current sensed by the current sensing unit 260. [

The minimum unit of the position of the rotor 113b detected through the Hall element 113c, that is, the rotation angle? Of the drum 124 may vary depending on the number of fixed magnets provided in the rotor 113b, In this embodiment, 15 degrees is the minimum unit, but it is not necessarily limited thereto.

The speed control unit 233 controls the proportional-integral (PI) control of the rotation speed of the rotor 113b detected by the position detection unit 231 so that the command current value is set so as to follow the command speed? Output. The dq axis rotation coordinate system having the d axis parallel to the magnetic flux direction and the q axis orthogonal to the d axis is defined, the command current outputted by the speed controller 233 is the d axis command current value Id * and q Can be expressed by the vector sum of the axis command current value Iq *.

The current control unit 235 performs proportional-integral (PI) control so that the current values Id and Iq sensed by the current sensing unit 260 follow the command current values Id * and Iq * Value Vd * and the q-axis command voltage value Vq *, respectively.

The coordinate conversion unit 237 converts the rotating coordinate system of the d-q axis and the fixed coordinate system of the uvw. The coordinate conversion unit 237 converts the command voltage value (Vd * / Vq *) input in the d-q axis rotation coordinate system into a three-phase command voltage value. The coordinate converter 237 converts the current of the fixed coordinate system sensed by the current sensing unit 260, which will be described later, into a d-q axis rotation coordinate system. In this case, the coordinate conversion unit 237 may convert the rotational position of the drum 113b detected by the position detection unit 231, which will be described later, 124) of the coordinate system.

The PWM (Pulse Width Modulation) operation unit 240 receives the signal of the uvw fixed coordinate system output from the motor control unit 230, and generates a PWM signal.

The inverter (inverter) 250 is a conversion device that generates an AC power of variable voltage and variable frequency from a constant or variable DC power source. The inverter 250 receives the PWM signal from the PWM operation unit 240 and directly controls the power input to the motor 113. The inverter 250 can control the frequency of the AC output power as well as the magnitude of the output voltage. According to the embodiment, the PWM operation unit 240 can be included in the inverter 250, and these inverters are generally referred to as PWM inverters.

The PWM operation unit 240 generates a PWM control signal for turning on / off each phase switch so that a fundamental wave voltage having the same magnitude (Volt-Second Average) and frequency as the command voltage values Vd * and Vq * Off drive pulse (Gating Pulse). In this process, a switching pattern can be determined to minimize unnecessary harmonics and switching loss. For this purpose, the optimal PWM scheme includes Optimal / Programmed PWM, Carrier Based PWM, space vector PWM, and the like are well known.

The laundry processing apparatus performs operations such as washing, rinsing, dewatering, drying, and the like in accordance with the set values through the control panel 114. The laundry processing apparatus operates in accordance with the amount of water Detailed parameters such as the rotational speed, the rotation pattern, and the operation time of the drum 124 are set, and the optimized operation is performed. The laundry processing apparatus performs the step of detecting the laundry amount before performing the above-described operations. In the following, the embodiments described describe the steps of detecting the amount of material, and the embodiments are not limited to detecting the amount of the material before any of the processes such as washing, rinsing, dewatering, and drying are performed, . In addition, the respective steps may be applied not only to sensing the amount of smoke before the water is supplied into the drum 124, but also to detecting the amount of the water after the water is supplied into the drum 124.

The pulse amount sensing unit 239 can determine the amount of the battery based on the current value applied to the motor 113 and the counter electromotive force of the motor 113. [ The current value at this time may be the current (Id, Iq) sensed by the current sensing unit 260, and the counter electromotive force may be sensed by the counter electromotive force sensing unit 270. According to the embodiment, the pulse amount sensing unit 239 may constitute one module with the counter electromotive force sensing unit 270.

 3 is a flowchart illustrating a method of controlling a laundry processing apparatus according to an embodiment of the present invention. FIG. 4 is a graph showing the rotation speed of the drum according to time when the laundry processing apparatus is operated according to the control method according to the embodiment of the present invention. 5 is a view for explaining a current sensing period in a method of controlling a laundry processing apparatus according to an embodiment of the present invention. Hereinafter, a method of controlling the laundry processing apparatus according to an embodiment of the present invention will be described with reference to FIGS. 3 to 5. FIG.

The control method of the laundry processing apparatus according to an embodiment of the present invention includes repeating the acceleration and braking of the drum 124 by a predetermined number of times and repeating acceleration and deceleration of the drum 124 detected in every acceleration period, And the counter electromotive force of the motor 113 detected in every braking period in which the drum 124 is braked. Hereinafter, accelerating and braking the drum 124 is referred to as a " discharge amount sensing operation ". In the present embodiment, the replenishment detection operation is repeated six times, but it is not necessarily limited thereto.

In the position alignment period ([t1, t2]), the position of the drum 124 is aligned (A1, alignment step). The stator 113a may be fixed so that the rotor 113b can be positively positioned. At this time, mainly the d-axis current can be output through the current controller 235. [ In this process, the resistance of the motor 113 and the error of the voltage information can be detected. Alignment of the drum 124 can be carried out during the volume sensing operations.

The drum 124 is accelerated from the position where the alignment is made (A2, [t2, t5]). The command speed? * Input to the speed control section 233 is the first speed? 1 and the rotation speed? Of the drum 124 is raised following the first speed? 1 (acceleration phase). The first speed omega 1 is preferably such that at least a portion of the bubble received in the drum 124 can flow at a rate at which the state of the bubble in the drum 124 can be changed and may be set at, have.

The drum 124 is not necessarily accelerated until it reaches the command speed? 1. That is, FIG. 4 shows that the drum 124 finally reaches the command speed? 1 in the acceleration step A2 and then the braking is performed. However, this is merely an illustrative example, The drum 124 is accelerated to follow a predetermined command speed. It is preferable that the command speeds in the respective acceleration stages have the same value.

When the same command speed [omega] * is requested, in order for the current speed [omega] to follow the command speed, the torque value generated by the motor 113 must be different depending on the burden or the load. On the current side, the current value applied to the motor 113 must be different. Therefore, the current value applied to the motor 113 or the indicator that the change is sensed following the current value can reflect the amount of the battery.

The amount of the laundry may be determined on the basis of the detected current value in an arbitrary section in which the drum 124 rotates. Preferably, the amount of the laundry is applied to the motor 113 detected in the section where the bag is lifted by the rotation of the drum 124 Can be determined based on the current value. Such a determination of the amount of waste can be made in the amount of waste detection unit 239.

The current value applied to the motor 113 is a current value output from the inverter 250 and can be sensed by the current sensing unit 260. The present current value can be represented by the d-axis current current value Id and the q-axis current current value Iq on the dq axis rotation coordinate system, and the component for generating the torque for the rotation of the rotor 113b is mainly Since it is the q-axis current component, it is preferable that the amount of the replenishment is determined based on the q-axis current value Iq.

The current value required to determine the amount of discharged fluid may be a sensed value from the moment when current is applied to the motor 113 to rotate the drum 124 in the stopped state, The current value detected at the beginning of rotation of the drum 124 due to various factors such as the state of the drum 124 and the arrangement of the drum 124 does not accurately reflect the amount of the drum 124. [ Therefore, it is preferable to determine the amount of discharged material based on the current current value sensed after the drum 124 has been rotated from the stopped state to some extent. In this respect, during the acceleration of the drum 124, the interval [t3 ([theta] 1, t4 ([theta] 2) where the position of the drum 124 changes from the first rotation angle 1 to the second rotation angle 2 )), The current (Id / Iq) is measured (A3, current sensing step). As described above, preferably, the replenishment amount can be determined based on the q-axis current value Iq among the measured current values.

5 shows a change in the position of the drum 124 as the motor 113 is driven, that is, a change from the first rotation angle 1 to the second rotation angle 2. P indicates the lowest point of the drum 124 whose position is aligned in the stopped state, and is hereinafter referred to as a reference point. 5 shows a state in which the reference point is raised to the rotational angles? 1 and? 2 as the drum 124 is rotated in the clockwise direction from the stopped state. H is a horizontal line passing through the center C of the drum 124, and V is a vertical line where the reference point is located in a state where the drum 124 is stopped. Hereinafter, the current sensing section is defined as a section from the first rotation angle [theta] 1 to the second rotation angle [theta] 2.

The pulse amount sensing unit 239 can obtain the current integrated value Iint obtained by integrating the current value Iq sensed in the current sensing period as shown in Equation 1 below.

[Formula 1]

 These current integral values are also obtained for the subsequent batch sensing operations. Hereinafter, the current integral values obtained in the current sensing period during the mth current sensing operation are referred to as Iint (m).

The surplus amount detection unit 239 determines a surplus amount based on the current value detected in the current sensing period. Preferably, the quantum sensing unit 239 can determine the quantum LD (LD) based on the current integration values.

Depending on the embodiment, the overdischarge (LD) can be obtained based on the sum of the current integral values. Each of the current integral values may be weighted (Ki). The current integration value close to the average of the current integration values may be given a weight value Ki having a larger value.

The braking step A5 is a step of braking the drum 124 to stop. The drum 124 is preferably braked by dynamic braking in which a simple circuit can be implemented, but regenerative braking is also possible.

The back electromotive force characteristic value can be detected in the braking section ([t5, t7]) in which the drum 124 is braked. The back electromotive force characteristic value is a characteristic value reflecting the back electromotive force generated by the motor 113 in the braking process, but may be the back electromotive force itself, but it is not necessarily limited to this, If it is detected, a value showing a change corresponding to the change of the counter electromotive force is sufficient.

The braking period ([t5, t7]) includes a period of detecting the back electromotive force characteristic value in which the back electromotive force characteristic value is sensed. The braking force of the motor 113 is controlled mainly by the braking force of the motor 124 in the section where the rotational speed of the drum 124 is lower than a certain level, It is preferable that the speed of the drum 124 is a certain section [t5, t6] in which the speed of the drum 124 is reduced to the second speed? 2, because the value of the generated counter electromotive force is insignificant. The second speed ([omega] 2) is preferably about 20 rpm, but is not necessarily limited thereto.

The counter electromotive force sensing unit 270 senses a counter electromotive force characteristic value. The counter electromotive force sensing unit 270 is electrically connected to an arbitrary section of the driving circuit that drives the motor 113 so long as the counter electromotive force characteristic value can show a change corresponding to the change of the counter electromotive force generated in the braking process of the motor 113 .

On the other hand, the circuit for driving the motor 113 can be expressed by the following equivalent equation.

[Formula 2]

Vin is the voltage applied from the inverter 250 to the motor 113, I is the current applied to the motor 113, and Vemf is the counter electromotive force of the motor 113. Leq is the equivalent inductance of the motor 113 and Req is the equivalent resistance of the motor 113 and values that can be obtained in the alignment step A1 or experimentally obtained in advance.

The counter electromotive force sensing unit 270 senses the voltage value Vin output from the inverter 250 and the current sensing unit 260 during the braking of the drum 124 by the motor control unit 230 And the counter electromotive force (Vemf) can be obtained based on the detected current value.

The back electromotive force characteristic value may be an average of the counter electromotive force measured in the counter electromotive force characteristic value sensing period ([t5, t6]). Particularly, when the sweep sensing operation is performed a plurality of times, the average of the counter electromotive forces have.

The torque generated by the motor 113 is proportional to the counter electromotive force (Vemf) and the current value (I). In the amount-of-waste determining step A9, the amount of discharged water is determined on the basis of the counter electromotive force Vemf sensed in the period in which the drum 124 is braked and the current value I sensed in the acceleration period of the drum 124. [ For example, the formula for obtaining the quantity can be expressed as follows.

[Formula 3]

The counter electromotive force generated in the braking process of the motor 113 can be represented by a vector having a q-axis component and a d-axis component, and the q-axis component mainly reflects the mass of these components. Therefore, the counter electromotive force Vemf may be the magnitude of the q-axis component of the vector, but it may be the magnitude of the whole vector.

The counter electromotive force sensing unit 270 includes a voltage sensing unit (not shown) for sensing a voltage applied from the inverter 250 to the motor 113, a voltage output unit for sensing a voltage output from the voltage sensing unit, And a coordinate converter (not shown) for converting the current output from the controller 260 into a two-phase rotation coordinate system.

6 is a flowchart illustrating a method of controlling a laundry processing apparatus according to another embodiment of the present invention. FIG. 7 is a graph showing the rotation speed of the drum according to time when the laundry processing apparatus is operated according to the control method according to another embodiment of the present invention. 8 is a view for explaining a current sensing period in the method of controlling a laundry processing apparatus according to an embodiment of the present invention.

The control method of the laundry processing apparatus according to another embodiment of the present invention detects the laundry in the current sensing period t3 (? 1), t4 (? 2) between the first rotation angle? 1 and the second rotation angle? The current value is corrected using the current value measured in another current sensing period after the current sensing period, and the amount of current is determined based on the corrected current value. 5 to 6, descriptions of the above-described embodiments may be applied as they are, except for steps A31 and A32, and therefore repeated description thereof will be omitted.

8 shows a change in the position of the drum 124 as the motor 113 is driven. P is the lowest point at the initial position of the aligned drum 124 and is hereinafter referred to as a reference point. 8 shows a state in which the reference point P is raised as the drum 124 is rotated clockwise at the initial position. H is a horizontal line passing through the center C of the drum 124 and V is a vertical line where the reference point P is located at the initial position of the drum 124. [ Hereinafter, the first current sensing period is defined as a period (t3 (? 1), t4 (? 2)) from the first rotation angle? 1 to the second rotation angle? 2, (T4 (? 2), t4 '(? 3 (? 3)) from the second rotation angle? 2 to the third rotation angle? 3 for convenience of explanation, )]).

It is preferable that the upper limit (? 3) of the second current sensing section does not exceed 90 degrees, and in particular, the second current sensing section is preferably set within a range in which the charging current can be rotated while being stuck to the carriage drum Do.

The amount of the battery can be determined based on the difference between the current value sensed in the first current sensing interval and the current sensed in the second current sensing interval. More specifically, the pulse amount sensing unit 239 outputs a first current integral value Iint1 obtained by integrating the current current value Iq1 sensed in the first current sensing period, A difference between the second current integral value Iint2 obtained by integrating the current current value Iq2 detected in the section can be obtained.

[Formula 4]

Hereinafter, the difference in the current integral value (the difference between the first current value and the second current value) obtained during the mth batch sensing operation is referred to as Idiff (m).

The surplus amount detection unit 239 determines a surplus amount based on the first current detected in the first current sensing period and the second current detected in the second current sensing period, A further counter electromotive force (Vemf) is required. In this case, the saturation sensing unit 239 may sense the first current integral value Iint 1 in the first current sensing period and the first current integration value Iint 1 in the second current sensing period. In particular, the saturation amount may be determined based on the difference between the first current and the second current. And the second current integral value Iint 2 in the second current sensing period, the back electromotive force (LD) is further determined. In this case, the replenishment amount can be expressed by the following equation (5).

[Formula 5]

When the drum 124 is started, scattering occurs in the amount of accumulated value depending on the position of the eccentricity because the load applied to the drum 124 varies depending on the position of the eccentricity and the torque required to drive the drum 124 is changed to be. Therefore, it is necessary to reduce the influence of the determined eccentricity value upon elimination of the influence of the position of the eccentricity when the amount of the eccentricity is determined. In this embodiment, in the first current sensing period t3 (? 1), t4 (Θ2), t4 '(θ3)] after the first current sensing period t3 (θ1), t4 (θ2)] is determined based on the current current value By using the sensed current value for correction, more accurate determination of the quantity is made.

Claims (17)

1. A control method for a laundry processing apparatus including a drum rotatably accommodated in a drum and a motor for rotating the drum,
An acceleration step of accelerating the drum at a first speed;
A current sensing step of sensing a current applied to the motor while the drum is accelerating at the first speed;
A braking step of braking the drum; And
And a counter electromotive force characteristic value sensing step of sensing a counter electromotive force characteristic value corresponding to a change in counter electromotive force of the motor while the drum is braked. The method according to claim 1,
The step of detecting the counter electromotive force characteristic value comprises:
Wherein the controller senses the counter electromotive force characteristic value in a section in which the drum is decelerated from the first speed to the second speed. The method according to claim 1,
Wherein the current sensing step comprises:
Wherein the controller senses a current applied to the motor in a period in which the position of the drum increases from a first rotation angle to a second rotation angle. The method of claim 3,
Wherein the pawl is rotated in a state where the pawl sticks to the drum between the first rotation angle and the second rotation angle. The method of claim 3,
Wherein the first rotation angle is greater than zero. The method according to claim 1,
Determining a quantity of the laundry based on the current value sensed in the current sensing step and the counter electromotive force characteristic value. The method according to claim 6,
The current value
Which is a difference between a value sensed in a first current sensing interval where the position of the drum increases from a first rotation angle to a second rotation angle and a value sensed in a second current sensing interval after the first current sensing interval, / RTI > 8. The method of claim 7,
The second current sensing period may include:
And a third rotation angle that is larger than the second rotation angle from the second rotation angle. A drum rotatably provided to receive the pouch;
A motor for rotating the drum;
A motor controller for controlling the motor to accelerate and brak down the drum at a first speed;
A current sensing unit sensing a current applied to the motor while the motor is accelerating at the first speed; And
And a counter electromotive force detecting unit for detecting a counter electromotive force characteristic value corresponding to a change in counter electromotive force of the motor while the motor is being controlled so that the drum is braked. 10. The method of claim 9,
Wherein the counter electromotive force sensing unit comprises:
And detects the counter electromotive force characteristic value in a section in which the drum is decelerated from the first speed to the second speed. 11. The method of claim 10,
The current applied to the motor,
Wherein a position of the drum is detected in a section where the position of the drum increases from a first rotation angle to a second rotation angle. 12. The method of claim 11,
Wherein the pawl is rotated in a state where the pawl sticks to the drum between the first rotation angle and the second rotation angle. 12. The method of claim 11,
Wherein the first rotation angle is greater than zero. 10. The method of claim 9,
Further comprising a dead amount detecting unit for determining a dead time based on a current value applied to the motor and a counter electromotive force characteristic detected by the counter electromotive force detecting unit. 17. The method of claim 16,
The amount-
A current value sensed in a first current sensing interval in which the position of the drum increases from a first rotation angle to a second rotation angle, a current sensed in a second current sensing interval after the first current sensing interval, A laundry processing device that determines the amount of laundry based on the back electromotive force characteristic value. 16. The method of claim 15,
The second current sensing period may include:
And a third rotation angle that is larger than the second rotation angle. 10. The method of claim 9,
Wherein the counter electromotive force characteristic value is obtained based on a current value sensed through the current sensing unit.

Images