Home appliance comprising motor and home appliance control method

Abstract

Provided are a home appliance including a motor, and a method for controlling a home appliance including a motor. The method for controlling a home appliance including a motor comprises the steps of: calculating a duty ratio for an inverter control signal for changing on / off states of a plurality of switches included in an inverter at an end time point of a square wave control; calculating a phase voltage of the motor on the basis of the inverter control signal; and on the basis of the phase voltage of the motor and a rotor position of the motor, configuring an initial voltage command for initiating a sinusoidal control, wherein a phase voltage of the motor based on the initial voltage command corresponds to a phase voltage of the motor based on the duty ratio.

Description

Home appliances including motors and methods for controlling home appliances

[0001] Embodiments of the present disclosure relate to a home appliance including a motor and a method for controlling the home appliance.

[0002] Home appliances such as vacuum cleaners, refrigerators, and air conditioners may include motors to drive compressors. These appliances may utilize brushless permanent magnet three-phase synchronous motors, such as brushless DC motors (BLDC motors).

[0003] These motors can be driven by various power supply methods, for example, sinusoidal or square wave. Typically, home appliances control the motor by configuring hardware and software designed for one of the power supply methods. Generally, sinusoidal power supply applies voltage to three of the three phases of the motor, which may increase the switching loss of the inverter. However, since the phase current applied to the motor is a sine wave form close to the fundamental frequency, the efficiency of the motor can be improved. In addition, since square wave power supply applies voltage to only two of the three phases of the motor, the switching loss of the inverter can be reduced compared to the sinusoidal power supply method. However, square wave power supply has the problem that the phase current applied to the motor is a square wave form, which increases harmonics and reduces the efficiency of the motor.

[0004] A method for controlling a home appliance including a motor according to one embodiment of the present disclosure includes the steps of calculating a duty ratio for an inverter control signal that changes the on / off states of a plurality of switches included in an inverter at the end point of square wave control, the step of calculating a phase voltage of the motor based on the inverter control signal, and the step of setting an initial voltage command for initiating sine wave control based on the phase voltage of the motor and a rotor position of the motor, wherein the phase voltage of the motor based on the initial voltage command corresponds to the phase voltage of the motor based on the duty ratio.

[0005] A method for controlling a home appliance including a motor according to one embodiment of the present disclosure further includes a step of detecting a phase current of the motor through a current sensor at the end point of sine wave control, a step of calculating a d-axis voltage and a q-axis voltage of the motor based on the phase current of the motor, and a step of setting an initial duty ratio command for initiating square wave control based on the d-axis voltage and the q-axis voltage of the motor, wherein the phase voltage of the motor based on the initial duty ratio command corresponds to a phase voltage of the motor according to the sine wave control.

[0006] A method for controlling a home appliance including a motor according to one embodiment of the present disclosure includes the steps of calculating a duty ratio for an inverter control signal applied to an inverter at an end time of square wave control, thereby setting an initial voltage command for initiating sine wave control, and the step of detecting a phase current of the motor at an end time of sine wave control, thereby setting an initial duty ratio command for initiating sine wave control, wherein a phase voltage applied to the motor at the start time of the sine wave control is the same as a phase voltage applied to the motor at an end time of the square wave control, and wherein the phase voltage applied to the motor at the start time of the square wave control is the same as a phase voltage applied to the motor at an end time of the sine wave control.

[0007] According to one embodiment of the present disclosure, a home appliance including a motor includes a motor, an inverter that generates an AC current from a DC power source and outputs an AC driving current to the motor, a current sensor that detects a phase current of the motor, a voltage sensor that detects a phase voltage of the motor, a memory that stores at least one instruction, and at least one processor. The at least one processor calculates a duty ratio for an inverter control signal that changes an on / off state of a plurality of switches included in the inverter at an end point of square wave control by executing the at least one instruction. The at least one processor calculates a phase voltage of the motor based on the inverter control signal. The at least one processor sets an initial voltage command for initiating a sinusoidal wave control based on the phase voltage of the motor and a rotor position of the motor. The phase voltage of the motor based on the initial voltage command is characterized in that it corresponds to a phase voltage of the motor based on the duty ratio.

[0008] FIG. 1 is a drawing showing the operation of a home appliance including a motor according to one embodiment of the present disclosure.

[0009] FIG. 2 is a block diagram showing the configuration of a sinusoidal controller according to one embodiment of the present disclosure.

[0010] FIG. 3 is a block diagram showing the configuration of a square wave controller according to one embodiment of the present disclosure.

[0011] FIG. 4 is a graph showing the phase current and PWM signal of a motor controlled by a sinusoidal current method according to one embodiment of the present disclosure.

[0012] FIG. 5 is a graph showing the phase current and PWM signal of a motor controlled by a square wave current method according to one embodiment of the present disclosure.

[0013] FIG. 6 is a block diagram illustrating an operation of a home appliance according to one embodiment of the present disclosure to switch a power supply method according to a speed command.

[0014] FIG. 7 is a flowchart illustrating a method for switching from a square wave transmission mode to a sinusoidal wave transmission mode according to one embodiment of the present disclosure.

[0015] FIG. 8 is a flowchart illustrating a method for switching from a sinusoidal current mode to a square wave current mode according to one embodiment of the present disclosure.

[0016] FIG. 9 is a diagram illustrating the operation of a home appliance including a motor according to one embodiment of the present disclosure.

[0017] FIG. 10 is a block diagram illustrating an operation of a home appliance according to one embodiment of the present disclosure to switch a power supply method according to a speed command and a battery voltage.

[0018] FIG. 11 is a graph for explaining the timing of switching the power supply method according to the speed command and battery voltage according to one embodiment of the present disclosure.

[0019] FIG. 12 is a graph of the phase current of a motor as it switches from a square wave current mode to a sinusoidal current mode according to one embodiment of the present disclosure.

[0020] FIG. 13 is a graph of the phase current of a motor as it switches from a sinusoidal current mode to a square wave current mode according to one embodiment of the present disclosure.

[0021] FIG. 14 is an example of a circuit diagram of a home appliance including a motor according to one embodiment of the present disclosure.

[0022] FIG. 15 is a detailed block diagram of a home appliance according to one embodiment of the present disclosure.

[0023] Fig. 16 is a flowchart illustrating the operation of a home appliance according to one embodiment of the present disclosure.

[0024] The terms used in this disclosure will be briefly explained, and one embodiment of the present disclosure will be specifically described.

[0025] The terms used in this disclosure are selected from widely used, current terms, taking into account the functions of one embodiment of the disclosure. However, these terms may vary depending on the intentions of those skilled in the art, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the description of the relevant embodiments of the disclosure. Therefore, the terms used in this disclosure should not be defined simply as names of terms, but rather based on the meanings of the terms and the overall content of the disclosure.

[0026] In this disclosure, the expression “at least one of a, b or c” may refer to “a”, “b”, “c”, “a and b”, “a and c”, “b and c”, “all of a, b and c”, or variations thereof.

[0027] Throughout this disclosure, when a part is said to "include" a certain component, this does not mean that other components are excluded, but rather that other components may be included, unless otherwise specifically stated. Furthermore, terms such as "part" and "module" described in this disclosure mean a unit that processes at least one function or operation, and the "part" and "module" may be implemented as hardware or software, or as a combination of hardware and software.

[0028] Below, with reference to the attached drawings, embodiments of the present disclosure are described in detail so that those skilled in the art can easily implement the present disclosure. However, one embodiment of the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts irrelevant to the description are omitted to clearly describe one embodiment of the present disclosure, and similar parts are designated with similar drawing reference numerals throughout the present disclosure.

[0029] FIG. 1 is a diagram illustrating the operation of a home appliance including a motor according to one embodiment of the present disclosure. FIG. 2 is a block diagram illustrating the configuration of a sine wave controller according to one embodiment of the present disclosure. FIG. 3 is a block diagram illustrating the configuration of a square wave controller according to one embodiment of the present disclosure.

[0030] Referring to FIG. 1, a home appliance (100) may include a battery (30), a DC link capacitor (40), an inverter (50), a motor (60), a current sensor (70), a voltage sensor (80), and a processor (110).

[0031] The home appliance (100) may be implemented in the form of, for example, a vacuum cleaner, a refrigerator, an air conditioner, a washing machine, a dryer, a dehumidifier, a clothing care device, a shoe care device, a cooking appliance, etc. The home appliance (100) may control a motor (60) for operations such as power control and output control. The motor (60) may supply driving power to drive a compressor (not shown).

[0032] The motor (60) outputs driving force to a predetermined home appliance function module of the home appliance (100). The motor (60) may be any motor including a stator on which a coil is wound and a rotor that rotates by a magnetic field generated by the coil. The motor (60) may receive an AC driving current from an inverter (50) and generate a constant torque. The motor (60) may correspond to a brushless permanent magnet three-phase synchronous motor. The motor (60) may be implemented in a form in which the stator has three phases, for example, U phase, V phase, and W phase.

[0033] An inverter (50) is a power conversion device having a plurality of switching elements and a plurality of diodes, and converts direct current power into alternating current power. One end of the inverter (50) may be connected to a DC link capacitor (40), and the other end may be connected to a motor (60). The inverter (50) receives direct current power, generates an alternating current driving current through a switching operation, and outputs the driving current to the motor (60). For example, the inverter (50) may convert the direct current power into an alternating voltage in the form of a pulse with an arbitrary variable frequency using a pulse width modulation (PWM) method, and drive the motor (60). The inverter (50) may include a pair of switching elements (upper switch - lower switch) corresponding to each phase of a three-phase motor. The inverter (50) may open and close the switching elements according to an inverter control signal received from the processor (110), thereby generating a driving current and outputting the driving current to each phase of the motor (60).

[0034] The battery (30) may correspond to the power module (1580 of FIG. 15) of the home appliance (100). The power module receives power from an external power source, converts it into the rated voltage and current of the home appliance (100), and supplies driving current to each component.

[0035] According to one embodiment of the present disclosure, a home appliance (100) may include a square wave current method and a sinusoidal wave current method in a manner of controlling the rotational speed of a motor (60). The processor (110) may include a square wave controller (300) for controlling the motor (60) using a square wave current method and a sinusoidal wave controller (200) for controlling the motor (60) using a sinusoidal wave current method.

[0036] The square wave energization method is a method of alternately applying high (H), low (LOW), and open (OPEN) voltages to each of the three-phase coils of the motor (60). In the square wave energization method, current is energized only in two of the three-phase coils of the motor (60), and a counter electromotive force may be generated in the remaining open single-phase coil through a change in the magnetic field that occurs when the rotor rotates. The counter electromotive force may be detected by a voltage sensor (80). The home appliance (100) may control the rotation speed of the motor (60) by rotating the rotor of the motor (60) through the counter electromotive force generated in the open single-phase coil. In addition, the home appliance (100) may detect the position of the rotor by detecting the zero-crossing point (ZCP), which is the point where the counter electromotive force of the open single-phase coil passes through 0. Accordingly, the home appliance (100) energizes each phase after a phase angle of 30 degrees has passed from the position of the detected rotor, so that the phase switching sequence of the three-phase coil can be known. The phase switching sequence indicates the order in which multiple switching elements of the inverter are opened and closed. The phase switching sequence can be determined according to the switching sequence of the inverter control signal. The square wave energization method is called the so-called 120-degree energization method.

[0037] The sine wave current conduction method is a method of conducting current through a three-phase coil. The home appliance (100) can detect the phase current applied to the three-phase coil through the current sensor (70). Since the phase current of the motor (60) is used to rotate the rotor of the motor (60), the home appliance (100) can determine the rotation speed of the motor (60) through the phase current of the motor (60). The home appliance (100) can control the rotation speed of the motor (60) by applying an inverter control signal to the inverter (50). The sine wave current conduction method is called the so-called 180-degree current conduction method. The sine wave current conduction method may include a vector pulse width modulation method (Space Vector Pulse Width Modulation; SVPWM), a discrete pulse width modulation method (Discrete PWM; DPWM), etc.

[0038] According to one embodiment of the present disclosure, a home appliance (100) can convert a sine wave conduction mode to a square wave conduction mode, or can convert a square wave conduction mode to a sine wave conduction mode. In one embodiment, the home appliance (100) can select an appropriate control mode among the sine wave conduction mode or the square wave conduction mode according to a speed command in order to efficiently control the motor (60). For example, the home appliance (100) can use the square wave conduction mode in order to minimize switching loss in an area where the home appliance (100) operates at low speed. For example, the home appliance (100) can use the sine wave conduction mode in order to maximize the efficiency of the motor (60) in an area where the home appliance (100) operates at high speed.

[0039] Additionally, in one embodiment of the present disclosure, the home appliance (100) can select an appropriate control method among a sine wave power supply method or a square wave power supply method depending on the battery voltage. For example, the home appliance (100) can use a square wave power supply method to reduce switching loss when the battery voltage of the home appliance (100) is low. For example, the home appliance (100) can use a sine wave power supply method when the battery voltage of the home appliance (100) is high.

[0040] According to one embodiment of the present disclosure, when switching the power supply mode, the home appliance (100) can perform a smooth transition, so-called seamless transition, so as to prevent the phase current of the motor (60) from changing excessively. According to one embodiment of the present disclosure, the home appliance (100) can control the phase voltage applied to the motor (60) immediately before the power supply mode is switched so that it is the same as the phase voltage applied to the motor (60) according to the switched power supply mode. For example, the home appliance (100) can use a predetermined voltage formula so that the phase voltage applied to the motor (60) at the start of the switched power supply mode is the same as the phase voltage applied to the motor (60) at the end of the existing power supply mode. By using the predetermined voltage formula, the home appliance (100) can maintain the phase voltage of the motor (60) immediately before the power supply mode is switched and the phase voltage of the motor (60) immediately after the switching to be the same.

[0041] Accordingly, the home appliance (100) can switch the power supply method immediately at a desired point in time, thereby driving the motor (60) more efficiently. In addition, an overcurrent problem that occurs when the phase voltage of the motor (60) changes excessively as the power supply method is switched can be prevented.

[0042] Hereinafter, the sine wave transmission method and the square wave transmission method will be further described with reference to FIGS. 1 to 5.

[0043] Referring to FIGS. 1 and 2, the processor (110) may include a sine wave controller (200) that controls the inverter (50) in a sine wave manner.

[0044] The current sensor (70) can detect the phase current of the motor (60). The current sensor (70) can transmit the detected phase current to the processor (110). The processor (110) can determine the rotation speed of the motor (60) based on the detected phase current. The current detected by the current sensor (70) can correspond to the phase current of the motor (60) supplied to the motor (60) from the inverter (50). In one embodiment, the current sensor (70) can be located between the negative pole of the DC link capacitor (40) and the inverter (50). Alternatively, in one embodiment, the current sensor (70) can be located between the inverter (50) and the motor (60). Alternatively, in one embodiment, the current sensor (70) can be connected in series to the bottom switch of the inverter (50). The current sensor (70) can include a shunt resistance, a current detection sensor, etc.

[0045] The sine wave controller (200) can control the inverter (50) in a sine wave conduction manner. The sine wave controller (200) can receive the phase current of the motor (60) detected from the current sensor (70). Since the phase current of the motor (60) is used to rotate the rotor of the motor (60), the sine wave controller (200) can estimate the rotation speed of the motor (60) through the phase current of the motor (60) received from the current sensor (70). The sine wave controller (200) can include a first speed controller (210), a current controller (220), a PWM generator (230), a shaft converter (240), and a speed calculator (250).

[0046] The first speed controller (210) can receive a speed command and a rotor speed and output a current command (torque command) that reduces the speed error. The first speed controller (210) can output a speed command (ω*) desired by the user.r ) and the rotor speed (ω r ) and a speed proportional integral controller (PI). The first speed controller (210) may include a speed command (ω* r ) and the rotor speed (ω r ) is input and the speed error is proportionally integrated to obtain the q-axis current command (i*). q ) is generated and outputted to the current controller (220).

[0047] The current controller (220) can receive a current command and a driving current and output a voltage command that reduces the current error. The current controller (220) can output the q-axis current command (i*) generated by the first speed controller (210). q ) and d-axis current command (i* d ) is input and a voltage command is generated and output. The current controller (220) generates a q-axis current command (i* q ) is passed through a current proportional integral controller (current PI controller) and a filter to obtain the q-axis voltage reference (V*). q ) is output to the PWM generator (230). For example, the current controller (220) outputs the q-axis current command (i* q ) and the q-axis detection current (i) converted to the axis by the motor phase current through the axis converter (240) q ) are compared, and the difference, i.e. the current error, is passed through the current proportional integral controller and filter to obtain the q-axis voltage command (V*). q ) is output to the PWM generator (230). Meanwhile, the current controller (220) converts the d-axis current command into a d-axis voltage command (V*) through another current proportional integral controller and a filter. d ) is output to the PWM generator (230). For example, the current controller (220) outputs the d-axis current command (i* d ) and the d-axis detection current (i) converted from the motor phase current d) are compared, and the difference, i.e. the current error, is passed through the current proportional integral controller and filter to obtain the d-axis voltage command (V*). d ) is output to the PWM generator (230). Here, the d-axis-q-axis voltage and the d-axis-q-axis current are values ​​on the synchronous coordinate system (d, q).

[0048] The PWM generator (230) can generate an inverter control signal that controls the switching element of the inverter (50) in the form of a PWM signal (pulse width modulation signal) based on a voltage reference. The PWM generator (230) can generate the inverter control signal by vector control. The PWM generator (230) converts the voltage reference of the synchronous coordinate system (d, q) into the voltage reference of the stationary coordinate system (α, β). For example, the PWM generator (230) can generate (V* d , V* q ) to (V* α , V* β ) is converted into. In addition, the PWM generator (230) converts the voltage command of the stationary coordinate system (α, β) to match the shape of the motor to be driven and outputs it. For example, the PWM generator (230) converts the voltage command of the stationary coordinate system (V* α , V* β ) to the three-phase voltage reference (V* u , V* v , V* w ) and outputs it to the inverter (40). The PWM generator (230) receives the q-axis voltage command (V*) from the current controller (220). q ) and d-axis voltage reference (V* d ) can be determined according to the three-phase voltage of the motor (60).

[0049] The axis converter (240) can convert the three-phase current detected by the current sensor (70) into two axes, the d-axis (direct axis) and the q-axis (quadra axis). The axis converter (240) can convert the d-axis detected current (i d ) and q-axis detection current (i q) can be obtained and output to the current controller (220). Here, the d-axis represents the direction of the rotor magnetic field, and the q-axis represents the direction perpendicular to the magnetic field.

[0050] The speed calculator (250) calculates the rotor speed (ω r ) can be calculated and output to the first speed controller (210). The first speed controller (210) can calculate the rotor speed (ω) received from the speed calculator (250). r ) and speed command (ω* r ) and compare the d-axis current command (i* d ) and q-axis current command (i* q ) can be created.

[0051] FIG. 4 is a graph showing the phase current and PWM signal of a motor controlled by a sinusoidal current method according to one embodiment of the present disclosure. Referring to FIG. 4, a processor (110) detects a driving current to generate an inverter control signal and outputs the signal to the gates of U, V, and W phases of a three-phase motor through an inverter (50). The switching elements (Q1 to Q6) of the inverter (50) are illustrated in FIG. 14. At this time, the phase current graph has a sinusoidal wave shape. Although only the phase current of one phase is illustrated, the current of three phases may be energized at 120-degree intervals.

[0052] Referring to FIGS. 1 and 3, the processor (110) may include a square wave controller (300) that controls the inverter (50) in a square wave manner.

[0053] The voltage sensor (80) can detect the driving voltage applied to the motor (60) from the inverter (50). The voltage sensor (80) can transmit the detected driving voltage to the processor (110). In addition, the voltage sensor (80) can detect the back electromotive force (back EMF) output to the coil according to the rotation of the rotor of the motor (60). The back electromotive force is an induced electromotive force induced in the winding of the motor (60) as the rotor of the motor (60) rotates. The detected back electromotive force can be used to detect the rotor position of the motor (60) in square wave control. For example, the voltage sensor (80) can detect the zero crossing point (ZCP), which is the point where the back electromotive force passes through 0.

[0054] The square wave controller (300) can control the inverter (50) in a square wave manner. The square wave controller (300) can receive a driving voltage detected from a voltage sensor (80). The square wave controller (300) can estimate the rotation speed and rotor position of the motor (60) through the driving voltage detected from the voltage sensor (80). A duty ratio for a PWM signal can be determined according to the rotation speed of the motor (60). A switching sequence can be determined according to the rotor position of the motor (60). The square wave controller (300) can include a second speed controller (310), a PWM generator (320), and a position / speed calculator (330).

[0055] The second speed controller (310) can receive a speed command and a rotor speed and output a duty ratio for an inverter control signal that reduces a speed error. For example, the second speed controller (310) can output a duty ratio for a speed command (ω*) desired by a user. r ) and the rotor speed (ω r) to generate a duty ratio command (v*) of an inverter control signal to reduce the speed error and output it to a PWM generator (320). The rotor speed can be received from a position / speed calculator (330). The three-phase voltage of the motor (60) can be determined according to the duty ratio command (v*) output by the second speed controller (310).

[0056] The PWM generator (320) can generate an inverter control signal according to the duty ratio based on the duty ratio command. The PWM generator (320) can transmit the inverter control signal according to the duty ratio to the inverter (50). The phase voltage of the motor (60) can be determined according to the duty ratio for the inverter control signal. The PWM generator (320) can generate a rotor position (θ r ) can be used to determine a switching sequence for turning the inverter (50) on / off. The high phase, low phase, and open phase of the three phases of the motor (60) can be determined according to the switching sequence output by the PWM generator (320).

[0057] The position / speed calculator (330) can receive the driving voltage detected from the voltage sensor (80). The position / speed calculator (330) can calculate the rotor speed (ω) based on the driving voltage. r ) can be calculated and output to the second speed controller (330). In addition, the position / speed calculator (330) can calculate the rotor position (θ) of the motor (60) based on the driving voltage. r ) can be detected. The position / speed calculator (330) can detect the rotor position (θ) to the PWM generator (320). r ) can be printed.

[0058] Meanwhile, the PWM generator (320) of the square wave controller (300) may be the same circuit as the PWM generator (230) of the sine wave controller (200) or may be a separate circuit.

[0059] FIG. 5 is a graph showing the phase current and PWM signal of a motor controlled by a square wave method according to one embodiment of the present disclosure. Referring to FIG. 5, the processor (110) can detect a driving voltage and generate an inverter control signal according to a duty ratio. Unlike FIG. 4, the waveform of the phase current has a square wave shape. In addition, for example, in a certain sequence, an inverter control signal in the form of a PWM may be applied to a first switching element (Q1), and an inverter control signal in an ON state may be applied to a sixth switching element (Q6). In this case, current may be applied to the U phase and the V phase, and the W phase may be opened.

[0060] FIG. 6 is a block diagram illustrating an operation of a home appliance according to one embodiment of the present disclosure to switch a power supply method according to a speed command.

[0061] In one embodiment of the present disclosure, the home appliance (100) can convert from a sinusoidal current mode to a square wave current mode, or vice versa. For example, in a region where the home appliance (100) operates at low speeds, the processor (110) can utilize a square wave current mode to minimize switching losses. For example, in a region where the home appliance (100) operates at high speeds, the home appliance (100) can utilize a sinusoidal current mode to maximize the efficiency of the motor (60).

[0062] The home appliance (100) can switch between power modes based on a user-set speed command. For example, if the speed command is above a critical speed, the home appliance (100) can switch from a square wave power mode to a sine wave power mode. For example, if the speed command is below a critical speed, the home appliance (100) can switch from a sine wave power mode to a square wave power mode.

[0063] In one embodiment of the present disclosure, the processor (110) may include a control selector (610) that selects a control method according to a speed command. The control selector (610) may be configured to select a control method according to a speed command (ω r *) can be selected according to the sine wave controller (200) or the square wave controller (300). The control selector (610) can provide an enable signal to the controller of the selected power supply type and a disable signal to the controller of the unselected power supply type. For example, the control selector (610) can be selected based on the speed command (ω r *) is less than the critical speed, an enable signal can be provided to the square wave controller (300) and a disable signal can be provided to the sine wave controller (200). For example, the control selector (610) can provide a speed command (ω r *) If the critical speed is greater than or equal to the critical speed, an enable signal can be provided to the sine wave controller (200) and a disable signal can be provided to the square wave controller (300).

[0064] According to one embodiment of the present disclosure, when switching the power supply method, the home appliance (100) can perform a smooth switch so that the phase current of the motor (60) does not change excessively. In one embodiment of the present disclosure, the home appliance (100) can match the phase voltage applied to the motor (60) at the end of the first power supply method and the phase voltage applied to the motor (60) at the start of the second power supply method. Here, when the first power supply method is a sine wave power supply method, the second power supply method may be a square wave power supply method, and when the first power supply method is a square wave power supply method, the second power supply method may be a sine wave power supply method.

[0065] According to one embodiment of the present disclosure, a home appliance (100) may first set an initial command value of the second power supply mode before switching from a first power supply mode to a second power supply mode. The initial command value may be a command value applied to a PWM generator that generates an inverter control signal at the start time of the second power supply mode. As the second power supply mode is started, an inverter control signal generated based on the initial command value is provided to an inverter (50), and the inverter (50) may apply a driving current to a motor (60) based on the inverter control signal. As the second power supply mode is started, a phase voltage applied to the motor (60) based on the inverter control signal may be the same as a phase voltage applied to the motor (60) at the end time of the first power supply mode.

[0066] In one embodiment of the present disclosure, when the first power supply method is a square wave power supply method and the second power supply method is a sinusoidal wave power supply method, the initial command value is an initial voltage command (v d e *, v q e *) may be included. Additionally, the initial command value may include the initial current command (i d e *, i q e *) may be included.

[0067] For example, the processor (110) can calculate the duty ratio for the inverter control signal applied to the inverter (50) at the end point of the square wave control. By calculating the duty ratio for the inverter control signal, the processor (110) can provide an initial voltage command (v) for initiating the sine wave control. d e *, v q e *) can be produced. In addition, the processor (110) can output an initial voltage command (v d e *, v q e *) based on the initial current command (i) to initiate sinusoidal controld e *, i q e *) can be produced. The processor (110) initial voltage command (v d e *, v q e *) and initial current command (i d e *, i q e *) based on which sine wave control can be initiated. In one embodiment of the present disclosure, the phase voltage applied to the three phases of the motor (60) at the start of the sine wave control can correspond to the phase voltage applied to the three phases of the motor (60) at the end of the square wave control. Hereinafter, a method for the processor (110) to switch from the square wave conduction mode to the sine wave conduction mode will be described by connecting FIG. 6 to FIG. 7.

[0068] In addition, in one embodiment of the present disclosure, when the first power supply method is a sine wave power supply method and the second power supply method is a square wave power supply method, the initial command value is an initial duty ratio command (v e *) may be included.

[0069] For example, the processor (110) can detect the phase current of the motor (60) at the end point of the sine wave control. By detecting the phase current of the motor (60), the processor (110) can provide an initial duty ratio command (v) to initiate the square wave control. e *) can be produced. The processor (110) can output an initial duty cycle command (v e *) based on which the square wave control can be initiated. In one embodiment of the present disclosure, the phase voltage applied to the three phases of the motor (60) at the initiation point of the square wave control can correspond to the phase voltage applied to the three phases of the motor (60) at the end point of the sine wave control. Hereinafter, a method for the processor (110) to switch from the sine wave conduction mode to the square wave conduction mode will be described by connecting FIG. 6 to FIG. 8.

[0070] FIG. 7 is a flowchart illustrating a method for switching from a square wave transmission mode to a sinusoidal wave transmission mode according to one embodiment of the present disclosure. FIG. 7 is described with reference to FIG. 6.

[0071] Referring to FIGS. 6 and 7, in operation S710, the home appliance (100) can calculate a duty ratio for an inverter control signal that changes the on / off states of a plurality of switches included in the inverter (50) at the end point of square wave control. The end point of square wave control may mean the point immediately before switching from square wave control to sine wave control.

[0072] The home appliance (100) can supply a square wave-shaped current to the motor (60) through the square wave controller (300). The home appliance (100) can detect the driving voltage of the motor (60) through the voltage sensor (80). The voltage sensor (80) can detect the driving voltage of the motor (60) and provide it to the processor (110).

[0073] The processor (110) can detect the rotation speed of the motor (60) based on the driving voltage of the motor (60). For example, the processor (110) can detect the rotation speed (ω) of the motor (60) through the position / speed calculator (330). r ) can be estimated.

[0074] The processor (110) can calculate a duty ratio to reduce a speed error between a speed command and the rotation speed of the motor (60) through the second speed controller (310). The processor (110) can generate an inverter control signal based on the duty ratio through the PWM generator (320). The inverter (50) can control the motor (60) using a driving current in the form of a square wave according to square wave control. At the end point of the square wave control, the processor (110) can calculate a phase voltage applied to the motor (60).

[0075] The processor (110) can detect the rotor position of the motor (60) based on the driving voltage of the motor (60). The processor (110) can detect the rotor position (θ) of the motor (60) through the position / speed calculator (330). r ) can be estimated. The processor (110) can estimate the rotor position (θ) of the motor (60). r ), a switching sequence for turning on and off a plurality of switches included in the inverter (50) can be determined. The processor (110) can generate an inverter control signal according to the switching sequence through the PWM generator (320). The inverter (50) can receive the inverter control signal according to the switching sequence and apply power to the three phases of the motor (60). Depending on the switching sequence, a high phase voltage, a low phase voltage, and an open phase voltage can be applied to the motor (60).

[0076] In operation 720, the home appliance (100) can calculate the phase voltage of the motor (60) based on the inverter control signal.

[0077] The processor (110) can control the on / off of the switch of the inverter (50) at a predetermined duty ratio according to a switching sequence based on the duty ratio and the rotor position. The processor (110) can calculate the phase voltage of the motor (60) output from the inverter (50) including the on / off switch. For example, the processor (110) can calculate the high phase voltage, the low phase voltage, and the open phase voltage of the motor (60).

[0078] For example, the phase voltage of the motor (60) can be calculated through the following mathematical expressions 1, 2, and 3.

[0079]

[0080]

[0081]

[0082] In mathematical expression 1, V PWMis the voltage of the first phase of the motor (60) connected to the switch that receives the inverter control signal in the form of PWM, and V dc is a DC power source, and ON duty represents the duty ratio. In mathematical expression 2, VLOW ON represents the voltage of the second phase of the motor (60) connected to the switch that receives the ON type inverter control signal. In mathematical expression 3, V Open represents the voltage of the third phase of the motor (60) connected to the open switch. ω r is the rotation speed of the motor (60), and λ PM is the counter electromotive force constant of the motor (60), and θ r indicates the rotor position of the motor (60).

[0083] The processor (110) can determine two phases of the three phases of the motor (60) that are energized and one phase that is open based on a switching sequence determined based on the rotor position. The processor (110) can calculate the voltages of the first and second phases of the three phases of the motor (60) that are energized and the voltage of the third phase that is open by applying the duty ratio determined based on the rotation speed to mathematical expressions 1, 2, and 3.

[0084] In operation 730, the home appliance (100) can set an initial voltage command to initiate sinusoidal control by performing coordinate transformation for the phase voltage of the motor (60).

[0085] The processor (110) can convert the three-phase voltage of the motor (60) into a voltage of the synchronous coordinate system (d, q) by considering the rotor angle of the motor (60). For example, the processor (110) can convert the three-phase voltage (Vu, Vv, Vw) into a Clarke and Park voltage (V) by using the determinant of the mathematical expression 4 below, thereby converting the two-dimensional components of the d-axis and q-axis voltages (V d , V q ) can be created.

[0086]

[0087]

[0088] In mathematical equation 4, is the d-axis, q-axis voltage, e.g. (V d , V q ) represents, is the voltage of U-phase, V-phase, W-phase, for example (V u , V v , V w ) represents. n represents the neutral axis. θ represents the rotor angle of the motor (60). The U-phase, V-phase, and W-phase voltages correspond to the first phase voltage, second phase voltage, and third phase voltage of the motor (60) calculated in mathematical expression 3.

[0089] The processor (110) can set the d-axis and q-axis voltages converted from the three-phase voltage of the motor (60) as initial commands for initiating sine wave control. For example, the processor (110) can set the d-axis voltage and the q-axis voltage as initial voltage commands of the current controller (220). For example, the current controller (220) can set the d-axis voltage as the initial d-axis voltage command (v) of the current controller (220). d e* ) and the q-axis voltage is set to the initial q-axis voltage command (v) of the current controller (220). q e* ) can be set (see Fig. 6).

[0090] Additionally, in one embodiment, the home appliance (100) can set an initial current command for initiating sinusoidal control based on an initial voltage command. The processor (110) can set the d-axis current and q-axis current calculated based on the q-axis voltage and d-axis voltage as the initial current command of the first speed controller (210).

[0091] The processor (110) provides an initial d-axis voltage command (v d e* ) and initial q-axis voltage reference (v q e*), the initial d-axis current command (i d e* ) and initial q-axis current command (i q e* ) can be produced. For example, the initial d-axis current command (i d e* ) and initial q-axis current command (i q e* ) can be calculated using mathematical formula 5.

[0092]

[0093]

[0094] In Equation 5, v e d is the d-axis voltage, v e q is the q-axis voltage, i e d is the d-axis current, i e q is the q-axis current, L d is the d-axis inductance, L q is the q-axis inductance, r s is the coil resistance of the motor (60), ω e represents the angular velocity of the motor (60).

[0095] The processor (110) is configured to use the initial d-axis voltage command (v) in mathematical expression 5. d e* ) and initial q-axis voltage reference (v q e* ), the initial d-axis current command (i d e* ) and initial q-axis current command (i q e* ) can be produced (see Fig. 6).

[0096] In operation S740, the home appliance (100) may initiate sine wave control based on the initial current command and the initial voltage command. The initiation point of sine wave control may refer to the point immediately after switching from square wave control to sine wave control.

[0097] The home appliance (100) can switch from square wave control to sine wave control. The home appliance (100) can switch the control method from square wave control to sine wave control based on a user's speed command or power command. For example, the home appliance (100) can switch from square wave control to sine wave control when the speed command is higher than a critical speed, but is not limited thereto. The processor (110) can apply a disable signal to the square wave controller (300) and an enable signal to the sine wave controller (200) through the control selector (610) to switch the control method from square wave control to sine wave control, but is not limited thereto.

[0098] The processor (110) can drive the motor (60) in a sinusoidal control manner based on the initial current command and the initial voltage command. For example, the processor (110) can drive the motor (60) in a sinusoidal control manner based on the initial d-axis voltage command (v d e* ), initial q-axis voltage reference (v q e* ), initial d-axis current command (i d e* ), and initial q-axis current command (i q e* ), the sine wave control can be initiated. For example, the current controller (220) may be configured to initiate the initial voltage command (v d e* , v q e* ) can be provided to the PWM generator (230). The PWM generator (230) provides an initial voltage command (v d e* , v q e*) can generate an inverter control signal that controls the switching element of the inverter (50) in the form of a PWM signal. The inverter (50) can control the motor (60) using a driving current in the form of a sine wave according to sine wave control. A phase voltage can be applied to the motor (60) based on the initial voltage command.

[0099] In one embodiment of the present disclosure, the phase voltage applied to the three phases of the motor (60) at the start of the sinusoidal control may correspond to the phase voltage applied to the three phases of the motor (60) at the end of the square wave control. For example, the phase voltage applied to the motor (60) based on the initial voltage command may be the same as the phase voltage of the motor (60) calculated at the end of the square wave control. For example, the phase voltage applied to the motor (60) based on the initial voltage command may be the same as the phase voltage of the motor (60) calculated using mathematical expressions 1, 2, and 3.

[0100] In one embodiment of the present disclosure, the home appliance (100) can calculate the initial voltage reference at the start time of the sine wave control based on the duty ratio calculated at the end time of the square wave control. The home appliance (100) can prevent an overcurrent problem that occurs when switching from the square wave control to the sine wave control by setting the initial voltage reference for starting the sine wave control and then switching to the sine wave control method. For example, according to the square wave control method, one of the three phases of the motor (60) is open, so the phase voltage may be 0 or close to 0. If the control method is switched to the sine wave control method without setting the initial voltage reference while one phase of the motor (60) is open, an overcurrent may occur because excessive current flows in the open state of the motor (60). According to one embodiment of the present disclosure, a home appliance (100) can maintain the voltage of the open phase of the motor (60) before and after switching to a sine wave control method after setting an initial voltage command. Accordingly, the home appliance (100) can switch the power supply method at a desired time and perform a smooth switch without overcurrent issues.

[0101] Fig. 8 is a flowchart illustrating a method for switching from a sinusoidal current mode to a square wave current mode according to one embodiment of the present disclosure. Fig. 8 is described with reference to Fig. 6.

[0102] Referring to FIGS. 6 and 8, in operation S810, the home appliance (100) can detect the phase current of the motor (60) through the current sensor (70) at the end point of the sine wave control. The end point of the sine wave control may mean the point immediately before switching from the sine wave control to the square wave control.

[0103] The home appliance (100) can supply a sine wave type current to the motor (60) through the sine wave controller (300). The home appliance (100) can detect the phase current of the motor (60) through the current sensor (70). The current sensor (70) can detect the phase current of the motor (60) and provide it to the processor (110). For example, the current sensor (70) can detect the three-phase current (i) of the motor (60). u , i v , i w ) can be detected.

[0104] The processor (110) can detect the rotation speed of the motor (60) based on the phase current of the motor (60). For example, the processor (110) can detect the rotation speed (ω) of the motor (60) through the speed calculator (250). r ) can be estimated.

[0105] The processor (110) can detect a current command to reduce a speed error between a speed command and the rotational speed of the motor (60) through the first speed controller (210). The processor (110) can receive a current command and a driving current through the current controller (220) and calculate a voltage command to reduce the current error. The processor (110) can generate an inverter control signal based on the voltage command through the PWM generator (230). The inverter (50) can control the motor (60) using a driving current in a sinusoidal form according to sinusoidal control. At the end point of the sinusoidal control, the processor (110) can calculate a phase voltage applied to the motor (60).

[0106] In operation S820, the home appliance (100) can calculate the d-axis voltage and q-axis voltage of the motor based on the phase current of the motor. In order to calculate the phase voltage of the motor (60), the home appliance (100) can obtain the d-axis and q-axis voltages of the motor (60) by converting the phase current of the motor (60).

[0107] The processor (110) can convert the three-phase current (iu, iv, iw) of the motor (60) into the q-axis current (iq) and the d-axis current (id) through the axis converter (240). The processor (110) can detect the q-axis voltage (vq) and the d-axis voltage (vd) based on the q-axis current (iq) and the d-axis current (id). For example, the q-axis voltage (v q ) is the q-axis current (i q ) and the resistance (r) of the motor (60) s ) can be calculated by multiplying them. For example, in sinusoidal control, since the d-axis represents the direction of the magnetic field of the rotor of the motor (60), the d-axis voltage (v d ) can be set to 0.

[0108] Alternatively, the processor (110) can obtain the d-axis and q-axis voltages of the motor (60) using mathematical expression 6.

[0109]

[0110]

[0111] Equation 6 is from Equation 5, v e d It represents an equation in which 0 is substituted into i q e and i d e may be the q-axis current and d-axis current converted from the phase current of the motor (60) through the axis converter (240). The processor (110) may calculate v corresponding to the q-axis voltage through mathematical expression 6. q e can be produced.

[0112] In operation S830, the home appliance (100) can set an initial duty ratio command for initiating square wave control based on the d-axis voltage and q-axis voltage of the motor (60).

[0113] The processor (110) can calculate the initial duty ratio for initiating square wave control using mathematical expression 7.

[0114]

[0115] In Equation 7, v q e is the q-axis voltage of the motor (60), Vdc is a direct current power source, and ON duty can represent the initial duty ratio.

[0116] The processor (110) has a q-axis voltage (v q e ) and direct current power (Vdc) to mathematical expression 7, the initial duty ratio can be calculated. The processor (110) can set the calculated initial duty ratio as an initial duty ratio command for initiating square wave control. For example, the second speed controller (310) can set the calculated initial duty ratio as an initial duty ratio command (v e *) can be set (see Fig. 6).

[0117] In operation S840, the home appliance (100) may initiate square wave control based on the initial duty ratio command. The initiation point of square wave control may mean the point immediately after switching from sine wave control to square wave control.

[0118] The home appliance (100) can switch from sine wave control to square wave control. The home appliance (100) can switch the control method from sine wave control to square wave control based on a user's speed command or power command. For example, the home appliance (100) can switch from sine wave control to square wave control when the speed command is lower than a critical speed, but is not limited thereto. The processor (110) can apply a disable signal to the sine wave controller (200) and an enable signal to the square wave controller (300) through the control selector (610) to switch the control method from sine wave control to square wave control, but is not limited thereto.

[0119] The processor (110) can drive the motor (60) in a square wave control manner based on the initial duty ratio command. For example, the processor (110) can drive the motor (60) in a square wave control manner based on the initial duty ratio command (ve *), the square wave control can be initiated. For example, the PWM generator (320) can initiate the initial duty ratio command (v e *) can generate an inverter control signal that controls the switching element of the inverter (50) in the form of a PWM signal. The inverter (50) can control the motor (60) using a driving current in the form of a square wave according to square wave control. Initial duty ratio command (v e *) Based on this, a phase voltage can be applied to the motor (60).

[0120] In one embodiment of the present disclosure, the phase voltage applied to the three phases of the motor (60) at the start of the square wave control may correspond to the phase voltage applied to the three phases of the motor (60) at the end of the sine wave control. For example, the phase voltage applied to the motor (60) based on the initial duty ratio command may be the same as the phase voltage of the motor (60) calculated at the end of the sine wave control. For example, the phase voltage applied to the motor (60) based on the initial duty ratio command may be the same as the phase voltage of the motor (60) calculated at the end of the sine wave control. Meanwhile, in the sine wave control, the phase voltage of the motor (60) may be calculated through the phase current of the motor (60) detected by the current sensor (70), but is not limited thereto. In the sine wave control, the phase voltage of the motor (60) may be calculated through various methods.

[0121] In one embodiment of the present disclosure, the home appliance (100) can calculate the initial duty ratio command at the start time of the square wave control based on the phase current of the motor (60) detected at the end time of the sine wave control. The home appliance (100) can prevent an overcurrent problem that occurs when switching from the sine wave control mode to the square wave control mode by setting the initial duty ratio command for starting the square wave control and then switching to the square wave control mode. The home appliance (100) according to one embodiment of the present disclosure can maintain the voltage of the open phase of the motor (60) before and after the switching of the control mode by setting the initial duty ratio command and then switching to the square wave control mode. Accordingly, the home appliance (100) can switch the energization mode at a desired time and perform a smooth switching in which the phase current of the motor (60) does not excessively change.

[0122] FIG. 9 is a diagram illustrating the operation of a home appliance including a motor according to one embodiment of the present disclosure. FIG. 10 is a block diagram illustrating the operation of a home appliance according to one embodiment of the present disclosure for switching power supply modes according to a speed command and battery voltage.

[0123] Referring to FIG. 9, the home appliance (100) may further include a battery voltage sensor (90) that detects the voltage of the battery (30), in addition to the battery (30), DC link capacitor (40), inverter (50), motor (60), current sensor (70), voltage sensor (80), and processor (110).

[0124] The battery voltage sensor (90) can detect the DC voltage of the battery (30). The battery voltage sensor (90) can transmit the detected battery voltage to the processor (110).

[0125] Referring to FIG. 10, a home appliance (100) according to one embodiment of the present disclosure can switch the power supply method to efficiently drive a motor (60) according to a speed command and a battery voltage.

[0126] A home appliance (100) according to one embodiment of the present disclosure can select an appropriate control method among a sine wave power supply method or a square wave power supply method depending on a speed command and a battery voltage.

[0127] For example, the home appliance (100) can switch the power supply mode according to the speed command set by the user. For example, in an area where the home appliance (100) operates at low speed, the processor (110) can use a square wave power supply mode to minimize switching loss. For example, in an area where the home appliance (100) operates at high speed, the home appliance (100) can use a sinusoidal wave power supply mode to maximize the efficiency of the motor (60).

[0128] For example, the home appliance (100) may use a square wave current method to reduce switching loss when the battery voltage of the home appliance (100) is low. For example, the home appliance (100) may use a sine wave current method when the battery voltage of the home appliance (100) is high.

[0129] A home appliance (100) according to one embodiment of the present disclosure can switch the power supply method according to a power command and a battery voltage.

[0130] The home appliance (100) may further include a power controller (1020). The power controller (1020) may receive a power command and a current power, and may calculate and output a speed command that reduces a power error. The power controller (1020) may further include a comparator that compares a power command (P*) desired by a user with the current power (P). For example, the power controller (1020) may receive a power command (P*) and a current power (P), proportionally integrate the power error, and calculate a speed command (ω*). r ) can be generated. The power controller (1020) generates a speed command (ω* r) can be output to the control selector (1010). In one embodiment, the power controller (1020) may be implemented as a separate processor from the processor (110). In this case, the power controller (1020) may be included in the main processor that controls the overall operation of the home appliance (100), but is not limited thereto. For example, the power controller (1020) may be implemented as a single processor with the processor (110).

[0131] In one embodiment, the power command (P*) may be a value determined according to the operating mode of the home appliance (100). For example, if the home appliance (100) is a vacuum cleaner, the operating modes of the vacuum cleaner may include low, medium, high, and jet modes. The power command may increase as the mode progresses from low, medium, high, and jet modes. In addition, a speed command may be determined based on the power command. For example, as the power command increases, the rotation command of the motor (60) may increase.

[0132] According to one embodiment of the present disclosure, a home appliance (100) can switch its power supply mode when the user changes the operating mode. For example, when the operating mode is changed from weak mode to jet mode, the home appliance (100) can switch from a square wave power supply mode to a sine wave power supply mode. When the operating mode is changed from weak mode to jet mode, the home appliance (100) can determine that the speed command is greater than a threshold speed and switch from a square wave power supply mode to a sine wave power supply mode.

[0133] Additionally, for example, the home appliance (100) may switch from a sine wave mode to a square wave mode when the driving mode changes from a jet mode to a weak mode. When the driving mode changes from a jet mode to a weak mode, the home appliance (100) may determine that the speed command is below a critical speed and switch from a sine wave mode to a square wave mode.

[0134] Meanwhile, the criteria for changing the driving mode for switching the power supply mode are not limited to the examples described above. For example, the power supply mode can also be switched in situations such as when the driving mode changes from weak mode to strong mode, as further detailed in Figure 11.

[0135] According to one embodiment of the present disclosure, a home appliance (100) can switch its power supply mode when the battery voltage changes. For example, when the battery voltage is above a threshold voltage, the home appliance (100) can switch from a square wave power supply mode to a sinusoidal power supply mode. For example, when the battery voltage is below a threshold voltage, the home appliance (100) can switch from a sinusoidal power supply mode to a square wave power supply mode.

[0136] An electrical appliance (100) according to one embodiment of the present disclosure can switch the power supply method by considering both the speed command and the battery voltage. The processor (110) can include a control selector (1010) that selects the control method according to the speed command and the battery voltage. The control selector (1010) selects the control method according to the speed command (ω r *) can be selected according to the sine wave controller (200) or the square wave controller (300). In addition, the control selector (1010) can select the sine wave controller (200) or the square wave controller (300) according to the battery voltage. The control selector (1010) can provide an enable signal to the controller of the selected power supply type and a disable signal to the controller of the unselected power supply type.

[0137] According to one embodiment of the present disclosure, when switching the power supply mode based on a speed command and battery voltage, the home appliance (100) can perform a smooth transition to prevent excessive changes in the phase current of the motor (60). This has been described in detail in FIGS. 6 to 8, and thus a detailed description thereof will be omitted.

[0138] FIG. 11 is a graph for explaining the timing of switching the power supply method according to the speed command and battery voltage according to one embodiment of the present disclosure.

[0139] Referring to FIG. 11, the home appliance (100) can determine when to switch the power supply method depending on the driving mode and battery voltage.

[0140] The home appliance (100) can determine the timing for switching the power supply method based on the reference line (1101) shown on the x-axis representing the rotation speed of the motor (60) and the y-axis representing the battery voltage. For example, the home appliance (100) can use the sine wave power supply method as the speed command increases based on the reference line (1101), and can use the square wave power supply method as the speed command decreases based on the reference line (1101). For example, the home appliance (100) can use the sine wave power supply method as the battery voltage increases based on the reference line (1101), and can use the square wave power supply method as the battery voltage decreases based on the reference line (1101).

[0141] For example, in the first type (1110), the home appliance (100) can switch the power supply mode when the operation mode is changed by the user. For example, the home appliance (100) can switch from a square wave power supply mode to a sinusoidal wave power supply mode as the speed command of the motor (60) increases according to the operation mode. For example, the home appliance (100) can switch from a square wave power supply mode to a sinusoidal wave power supply mode as the speed command increases above approximately 44,000 rpm.

[0142] For example, in the second type (1120), the home appliance (100) can switch the power supply mode depending on the battery voltage. For example, the home appliance (100) can switch from a sinusoidal power supply mode to a square wave power supply mode as the battery voltage decreases below the full-charge voltage (V_max).

[0143] Fig. 12 is a graph of the phase current of a motor as it switches from a square wave mode to a sinusoidal mode according to one embodiment of the present disclosure. Fig. 13 is a graph of the phase current of a motor as it switches from a sinusoidal mode to a square wave mode according to one embodiment of the present disclosure.

[0144] Referring to FIG. 12, a home appliance (100) according to one embodiment of the present disclosure can stably switch from a first power supply mode to a second power supply mode when the rotation angle is 220 degrees. Furthermore, the home appliance (100) can stably switch from the first power supply mode to the second power supply mode when the rotation angle is 250 degrees. Here, the first power supply mode may be a square wave power supply mode and the second power supply mode may be a sine wave power supply mode.

[0145] Referring to FIG. 13, a home appliance (100) according to one embodiment of the present disclosure can stably switch from a first power supply mode to a second power supply mode when the rotation angle is 60 degrees. Furthermore, the home appliance (100) can stably switch from the first power supply mode to the second power supply mode when the rotation angle is 90 degrees. Here, the first power supply mode may be a sine wave power supply mode and the second power supply mode may be a square wave power supply mode.

[0146] Referring to FIGS. 12 and 13, the home appliance (100) can first set the initial command value of the second power supply mode before switching from the first power supply mode to the second power supply mode. Accordingly, the home appliance (100) can match the phase voltage of the motor (60) at the end of the first power supply mode and the phase voltage of the motor (60) at the start of the second power supply mode.

[0147] The home appliance (100) can stably switch the power supply mode even if the point in time when the phase current passes the zero current according to the sinusoidal control and the point in time when the counter electromotive force passes the zero crossing point (ZCP) according to the square wave control do not correspond while the rotation angle changes from 0 to 360 degrees. For example, the home appliance (100) can stably switch the power supply mode even if the rotation angle is not 30, 90, 150, 210, 270, or 330. Accordingly, the home appliance (100) can quickly switch the power supply mode at any timing.

[0148] FIG. 14 is an example of a circuit diagram of a home appliance including a motor according to one embodiment of the present disclosure.

[0149] In Fig. 14, the inverter (50) may include a plurality of switching elements (Q1, Q2, Q3, Q4, Q5, Q6) and a plurality of diodes. The switching element pair of the first switching element (Q1) and the fourth switching element (Q4) may correspond to the U phase of the motor (60), the switching element pair of the third switching element (Q3) and the sixth switching element (Q6) may correspond to the V phase of the motor (60), and the switching element pair of the fifth switching element (Q5) and the second switching element (Q2) may be positioned to correspond to the W phase of the motor (60).

[0150] The current sensor (70) may be located between the cathode of the DC link capacitor (40) and the inverter (50). The current sensor (70) may be a shunt resistance.

[0151] The voltage sensor (80) is located between the inverter (50) and the motor (60) and can detect the driving voltage applied from the inverter (50) to the motor (60). The voltage sensor (80) is shown as detecting all three-phase driving voltages, but may also detect only one-phase driving voltage. The voltage sensor (80) may include a resistor.

[0152] The battery voltage sensor (90) may be located between the DC link capacitor (40) and the inverter (50). The battery voltage sensor (90) may include a resistor.

[0153] FIG. 15 is a detailed block diagram of a home appliance according to one embodiment of the present disclosure.

[0154] Referring to FIG. 15, a home appliance (100) according to one embodiment of the present disclosure may correspond to a home appliance (1500). The home appliance (1500) according to one embodiment of the present disclosure includes a sensor (1510), an output interface (1520), an input interface (1530), a memory (1540), a communication module (1550), a home appliance function module (1560), a power module (1580), and a processor (1590). The home appliance (1500) may be configured with various combinations of the components illustrated in FIG. 19, and not all of the components illustrated in FIG. 19 are essential components.

[0155] The home appliance (1500) of FIG. 19 corresponds to the home appliance (100) described in FIG. 1, and the processor (1590) corresponds to the processor (110) described in FIG. 1.

[0156] The sensor (1510) may include various types of sensors, for example, the sensor (1510) may include various types of sensors such as a pressure gauge, a current sensor, an image sensor, an infrared sensor, an ultrasonic sensor, a lidar sensor, a human detection sensor, a motion detection sensor, a proximity sensor, and an illuminance sensor. Since the function of each sensor can be intuitively inferred from its name by those skilled in the art, a detailed description thereof will be omitted.

[0157] The output interface (1520) may include a display (1521), a speaker (1522), etc. The output interface (1520) outputs various notifications, messages, information, etc. generated by the processor (1590).

[0158] The input interface (1530) may include keys (1531), a touch screen (1532), etc. The input interface (1530) receives user input and transmits it to the processor (1590).

[0159] The memory (1540) stores various information, data, commands, programs, etc. required for the operation of the home appliance (1500). The memory (1540) may include at least one of volatile memory and non-volatile memory, or a combination thereof. The memory (1540) may include at least one type of storage medium among a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (e.g., SD or XD memory, etc.), a RAM (Random Access Memory), a SRAM (Static Random Access Memory), a ROM (Read-Only Memory), an EEPROM (Electrically Erasable Programmable Read-Only Memory), a PROM (Programmable Read-Only Memory), a magnetic memory, a magnetic disk, and an optical disk. In addition, the home appliance (1500) may also operate a web storage or cloud server that performs a storage function on the Internet.

[0160] The communication module (1550) may include at least one or a combination of a short-range communication module (1552) or a long-range communication module (1554). The communication module (1550) may include at least one antenna for wirelessly communicating with another device.

[0161] The short-range wireless communication module (1552) may include, but is not limited to, a Bluetooth communication module, a BLE (Bluetooth Low Energy) communication module, a near field communication module, a WLAN (Wi-Fi) communication module, a Zigbee communication module, an infrared (IrDA, infrared Data Association) communication module, a WFD (Wi-Fi Direct) communication module, a UWB (ultrawideband) communication module, an Ant+ communication module, a microwave (uWave) communication module, etc.

[0162] The remote communication module (1554) may include a communication module that performs various types of remote communication and may include a mobile communication unit. The mobile communication unit transmits and receives wireless signals with at least one of a base station, an external terminal, and a server on a mobile communication network. Here, the wireless signals may include various types of data according to the transmission and reception of voice call signals, video call signals, or text / multimedia messages.

[0163] The home appliance function module (1560) includes an operation module that performs the original function of the home appliance (1500). The home appliance function module (1560) may include a compressor (1961), a motor (60), and an inverter (50).

[0164] The power module (1580) is connected to a power source and supplies power to the home appliance (1500).

[0165] The processor (1590) controls the overall operation of the home appliance (1500). The processor (1590) can control components of the home appliance (1500) by executing a program stored in the memory (1540).

[0166] The processor (1590) may be implemented as one or more processors. The processor (1590) may execute instructions or commands stored in the memory (1940) to perform a predetermined operation. In addition, the processor (1590) controls the operation of components provided in the home appliance (1500). The processor (1590) may include at least one of a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), or a Neural Processing Unit (NPU), or a combination thereof.

[0167] Fig. 16 is a flowchart illustrating the operation of a home appliance according to one embodiment of the present disclosure.

[0168] Referring to FIG. 16, in operation S1610, the home appliance (100) can set an initial voltage command for initiating sine wave control by calculating a duty ratio for an inverter control signal applied to the inverter (50) at the end point of square wave control. The home appliance (100) can initiate sine wave control based on the initial voltage command. The phase voltage applied to the motor (60) at the start point of sine wave control may be the same as the phase voltage applied to the motor (60) at the end point of square wave control. Specific details regarding operation S1610 are described in FIGS. 6 and 7.

[0169] In operation S1620, the home appliance (100) can set an initial duty ratio command for initiating square wave control by detecting the phase current of the motor (60) at the end point of the sine wave control. The home appliance (100) can initiate square wave control based on the initial duty ratio command. The phase voltage applied to the motor (60) at the start point of the square wave control can be the same as the phase voltage applied to the motor (60) at the end point of the sine wave control. Specific details regarding operation S1620 are described in FIGS. 6 and 8.

[0170] A control method of a home appliance (100) including a motor (60) according to one embodiment of the present disclosure includes a step of calculating a duty ratio for an inverter control signal that changes the on / off states of a plurality of switches included in an inverter (50) at the end point of square wave control, a step of calculating a phase voltage of the motor (60) based on the inverter control signal, and a step of setting an initial voltage command for initiating sine wave control based on the phase voltage of the motor (60) and the rotor position of the motor (60). The control method of the home appliance (100) is characterized in that the phase voltage of the motor (60) based on the initial voltage command corresponds to the phase voltage of the motor (60) based on the duty ratio.

[0171] A step of calculating a duty ratio for an inverter control signal according to one embodiment of the present disclosure may include a step of detecting a driving voltage of a motor (60) through a voltage sensor (80), a step of detecting a rotational speed of the motor (60) based on the driving voltage of the motor (60), and a step of calculating a duty ratio for reducing a speed error between a speed command and the rotational speed of the motor (60).

[0172] The step of calculating the phase voltage of the motor (60) according to one embodiment of the present disclosure may include the step of detecting the driving voltage of the motor (60) through the voltage sensor (80), the step of detecting the rotor position of the motor (60) based on the driving voltage of the motor (60), and the step of calculating the phase voltage of the motor (60) output from the inverter (50) turned on and off according to the switching sequence based on the rotor position and duty ratio of the motor (60).

[0173] The step of calculating the phase voltage of the motor (60) according to one embodiment of the present disclosure is characterized by using the following formula,

[0174] (1)

[0175] (2)

[0176] (3)

[0177] V PWM is the voltage of the first phase connected to the switch that receives the inverter control signal in the form of PWM, and V dc is a DC power supply, ON duty is the duty ratio, and V LOW ON is the second phase voltage connected to the switch receiving the ON signal, and V Open is the voltage of the third phase connected to the open switch, and ω r is the rotation speed of the motor (60), and λ PM is the counter electromotive force constant of the motor (60), and θ r can indicate the rotor position of the motor (60).

[0178] A method for controlling a home appliance (100) including a motor (60) according to one embodiment of the present disclosure may further include a step of calculating an initial current command based on an initial voltage command, and a step of initiating sinusoidal control based on the initial voltage command and the initial current command.

[0179] A method for controlling a home appliance (100) including a motor (60) according to one embodiment of the present disclosure further includes a step of detecting a phase current of the motor (60) through a current sensor (70) at the end point of sine wave control, a step of calculating a d-axis voltage and a q-axis voltage of the motor (60) based on the phase current of the motor (60), and a step of setting an initial duty ratio command for initiating square wave control based on the d-axis voltage and the q-axis voltage of the motor (60). The phase voltage of the motor (60) based on the initial duty ratio command is characterized in that it corresponds to the phase voltage of the motor (60) according to the sine wave control.

[0180] The step of calculating the d-axis voltage and the q-axis voltage of the motor (60) according to one embodiment of the present disclosure is characterized by using the following formula,

[0181]

[0182]

[0183] v d e is the d-axis voltage, v q e is the q-axis voltage, i d e is the d-axis current, i q e is the q-axis current, L d is the d-axis inductance, L q is the q-axis inductance, r s can represent the coil resistance of the motor (60), and ωe can represent the angular velocity of the motor (60).

[0184] The step of setting the initial duty ratio command for square wave control according to one embodiment of the present disclosure is characterized by using the following formula,

[0185]

[0186] v q e is the q-axis voltage of the motor (60), and V dc is a DC power source, and ON duty can represent the initial duty ratio command.

[0187] A method for controlling a home appliance (100) including a motor (60) according to one embodiment of the present disclosure includes a step of calculating a duty ratio for an inverter control signal applied to an inverter (50) at the end point of square wave control, thereby setting an initial voltage command for initiating sine wave control, and a step of detecting a phase current of the motor (60) at the end point of sine wave control, thereby setting an initial duty ratio command for initiating sine wave control. The phase voltage applied to the motor (60) at the start point of sine wave control is characterized in that it is the same as the phase voltage applied to the motor (60) at the end point of square wave control. The phase voltage applied to the motor (60) at the start point of square wave control is characterized in that it is the same as the phase voltage applied to the motor (60) at the end point of sine wave control.

[0188] A method for controlling a home appliance (100) including a motor (60) according to one embodiment of the present disclosure may include a step of switching from square wave control to sine wave control when the speed command is greater than or equal to a critical speed, and a step of switching from sine wave control to square wave control when the speed command is less than or equal to the critical speed.

[0189] A method for controlling a home appliance (100) including a motor (60) according to one embodiment of the present disclosure may include a step of switching from sinusoidal control to square wave control when the battery voltage is below a threshold voltage.

[0190] The step of setting an initial voltage command for initiating sine wave control by calculating a duty ratio for an inverter control signal applied to an inverter (50) according to one embodiment of the present disclosure may include a step of calculating a duty ratio for an inverter control signal that changes the on / off states of a plurality of switches included in the inverter (50) at the end point of square wave control, a step of calculating a phase voltage of the motor (60) based on the inverter control signal, and a step of setting an initial voltage command for initiating sine wave control based on the phase voltage of the motor (60) and the rotor position of the motor (60).

[0191] The step of setting an initial duty ratio command for initiating square wave control by detecting the phase current of the motor (60) at the end point of the sine wave control according to one embodiment of the present disclosure may include a step of detecting the phase current of the motor (60) detected through the current sensor (70) at the end point of the sine wave control, a step of calculating the d-axis voltage and the q-axis voltage of the motor (60) based on the phase current of the motor (60), and a step of setting an initial duty ratio command for initiating square wave control based on the d-axis voltage and the q-axis voltage of the motor (60).

[0192] According to one embodiment of the present disclosure, a home appliance (100) includes a motor (60), an inverter (50) that generates an AC current from a DC power source and outputs an AC driving current to the motor (60), a current sensor (70) that detects a phase current of the motor (60), a voltage sensor (80) that detects a phase voltage of the motor (60), a memory (1940) that stores at least one instruction, and at least one processor (110). The at least one processor (110) calculates a duty ratio for an inverter control signal that changes an on / off state of a plurality of switches included in the inverter (50) at the end point of square wave control as the at least one instruction is executed. The at least one processor (110) calculates a phase voltage of the motor (60) based on the inverter control signal. The at least one processor (110) sets an initial voltage command for initiating a sinusoidal control based on the phase voltage of the motor (60) and the rotor position of the motor (60). At least one processor (110) is characterized in that the phase voltage of the motor (60) based on the initial voltage command corresponds to the phase voltage of the motor (60) based on the duty ratio.

[0193] At least one processor (110) according to one embodiment of the present disclosure can detect a driving voltage of a motor (60) through a voltage sensor (80) by executing at least one instruction. At least one processor (110) can detect a rotational speed of the motor (60) based on the driving voltage of the motor (60). At least one processor (110) can calculate a duty ratio to reduce a speed error between a speed command and the rotational speed of the motor (60).

[0194] At least one processor (110) according to one embodiment of the present disclosure can detect a driving voltage of a motor (60) through a voltage sensor (80) by executing at least one instruction. At least one processor (110) can detect a rotor position of the motor (60) based on the driving voltage of the motor (60). At least one processor (110) can calculate a phase voltage of the motor (60) output from an inverter (50) that is turned on and off according to a switching sequence based on the rotor position and duty ratio of the motor (60).

[0195] At least one processor (110) according to one embodiment of the present disclosure detects the phase voltage of the motor (60) by using the following formula, upon executing at least one instruction:

[0196] (1)

[0197] (2)

[0198] (3)

[0199] V PWM is the voltage of the first phase connected to the switch that receives the inverter control signal in the form of PWM, and V dc is a DC power supply, ON duty is the duty ratio, and V LOW ON is the second phase voltage connected to the switch receiving the ON signal, and V Open is the voltage of the third phase connected to the open switch, and ω r is the rotation speed of the motor (60), and λ PM is the counter electromotive force constant of the motor (60), and θ r can indicate the rotor position of the motor (60).

[0200] At least one processor (110) according to one embodiment of the present disclosure may, upon executing at least one instruction, calculate an initial current command based on an initial voltage command. At least one processor (110) may initiate sinusoidal control based on the initial voltage command and the initial current command.

[0201] At least one processor (110) according to one embodiment of the present disclosure can detect the phase current of the motor (60) through the current sensor (70) at the end point of the sinusoidal control by executing at least one instruction. At least one processor (110) can calculate the d-axis voltage and the q-axis voltage of the motor (60) based on the phase current of the motor (60). At least one processor (110) can set an initial duty ratio command for initiating the square wave control based on the d-axis voltage and the q-axis voltage of the motor (60).

[0202] At least one processor (110) according to one embodiment of the present disclosure sets an initial duty ratio command for square wave control using the following formula, upon executing at least one instruction:

[0203]

[0204] v q e is the q-axis voltage of the motor (60), and V dc is a DC power source, and ON duty can represent the initial duty ratio command.

[0205] A device-readable storage medium may be provided in the form of a non-transitory storage medium. Here, the term "non-transitory storage medium" simply means a tangible device that does not contain signals (e.g., electromagnetic waves). This term does not distinguish between cases where data is permanently stored in the storage medium and cases where data is temporarily stored. For example, a "non-transitory storage medium" may include a buffer in which data is temporarily stored.

[0206] According to one embodiment, the method according to various embodiments disclosed in the present document may be provided as included in a computer program product. The computer program product may be traded as a product between a seller and a buyer. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or may be distributed online (e.g., downloaded or uploaded) through an application store or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product (e.g., a downloadable app) may be temporarily stored or temporarily generated in a machine-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or an intermediary server.

Claims

1. A method for controlling a home appliance (100) including a motor (60), A step for calculating a duty ratio for an inverter control signal that changes the on / off state of a plurality of switches included in an inverter (50) at the end point of square wave control; A step of calculating the phase voltage of the motor (60) based on the inverter control signal; and It includes a step of setting an initial voltage command for initiating sinusoidal control based on the phase voltage of the motor (60) and the rotor position of the motor (60). A method, characterized in that the phase voltage of the motor (60) based on the initial voltage command corresponds to the phase voltage of the motor (60) based on the duty ratio.

2. In paragraph 1, The step of calculating the duty ratio for the above inverter control signal is: A step of detecting the driving voltage of the motor (60) through a voltage sensor (80); A step of detecting the rotation speed of the motor (60) based on the driving voltage of the motor (60); and A method comprising a step of calculating the duty ratio for reducing a speed error between a speed command and the rotation speed of the motor (60).

3. In paragraph 1 or 2, The step of calculating the phase voltage of the above motor (60) is: A step of detecting the driving voltage of the motor (60) through a voltage sensor (80); A step of detecting the rotor position of the motor (60) based on the driving voltage of the motor (60); and A method comprising the step of calculating the phase voltage of the motor (60) output from the inverter (50) that is turned on and off according to a switching sequence based on the rotor position and the duty ratio of the motor (60).

4. In any one of paragraphs 1 to 3, The step of calculating the phase voltage of the above motor (60) is: characterized by using the following formula, (1) (2) (3) V PWM is the voltage of the first phase connected to the switch that receives the inverter control signal in the form of PWM, and V dc is a DC power supply, ON duty is the above duty ratio, and V LOW ON is the voltage of the second phase connected to the switch receiving the ON signal, and V Open is the voltage of the third phase connected to the open switch, and ω r is the rotation speed of the above motor (60), and λ PM is the counter electromotive force constant of the above motor (60), and θ r A method for indicating the rotor position of the above motor (60).

5. In any one of paragraphs 1 to 4, The above method, A step of calculating an initial current command based on the initial voltage command; and A method further comprising the step of initiating the sine wave control based on the initial voltage command and the initial current command.

6. In any one of paragraphs 1 to 5, The above method, At the end point of sinusoidal control, a step of detecting the phase current of the motor (60) through a current sensor (70); A step of calculating the d-axis voltage and q-axis voltage of the motor (60) based on the phase current of the motor (60); and Further comprising a step of setting an initial duty ratio command for initiating square wave control based on the d-axis voltage and q-axis voltage of the above motor (60), A method, characterized in that the phase voltage of the motor (60) based on the initial duty ratio command corresponds to the phase voltage of the motor (60) according to the sine wave control.

7. In paragraph 6, The step of calculating the d-axis voltage and q-axis voltage of the above motor (60) is as follows: characterized by using the following formula, v d e is the d-axis voltage, v q e is the q-axis voltage, i d e is the d-axis current, i q e is the q-axis current, L d is the d-axis inductance, L q is the q-axis inductance, r s A method in which ωe represents the coil resistance of the motor (60) and ωe represents the angular velocity of the motor (60).

8. In paragraph 6 or 7, The step of setting the initial duty ratio command for the above square wave control is as follows. characterized by using the following formula, v q e is the q-axis voltage of the above motor (60), and V dc is a direct current power source, and ON duty represents the initial duty ratio command, method.

9. In a method for controlling a home appliance (100) including a motor (60), A step for setting an initial voltage command for initiating sine wave control by calculating a duty ratio for an inverter control signal applied to an inverter (50) at the end point of sine wave control; and It includes a step of setting an initial duty ratio command for initiating square wave control by detecting the phase current of the motor (60) at the end point of sine wave control, The phase voltage applied to the motor (60) at the start of the sinusoidal control is the same as the phase voltage applied to the motor (60) at the end of the square wave control. A method characterized in that the phase voltage applied to the motor (60) at the start of the square wave control is the same as the phase voltage applied to the motor (60) at the end of the sine wave control.

10. In paragraph 9, The above method, A step of switching the square wave control to sine wave control according to the above speed command being greater than or equal to the critical speed; and A method comprising the step of switching the sinusoidal control to the square wave control when the speed command is less than the threshold speed.

11. In clause 9 or 10, The above method, A method comprising the step of switching the sine wave control to the square wave control when the battery voltage is below a threshold voltage.

12. In any one of paragraphs 9 to 11, The step of setting the initial voltage command for initiating sine wave control by calculating the duty ratio for the inverter control signal applied to the above inverter (50) is as follows. A step of calculating a duty ratio for an inverter control signal that changes the on / off state of a plurality of switches included in an inverter (50) at the end point of the above square wave control; A step of calculating the phase voltage of the motor (60) based on the inverter control signal; and A method comprising the step of setting an initial voltage command for initiating sinusoidal control based on the phase voltage of the motor (60) and the rotor position of the motor (60).

13. In any one of paragraphs 9 to 12, The step of setting the initial duty ratio command for initiating square wave control by detecting the phase current of the motor (60) at the end point of the above sine wave control is as follows. At the end point of the above sine wave control, a step of detecting the phase current of the motor (60) through a current sensor (70); A step of calculating the d-axis voltage and q-axis voltage of the motor (60) based on the phase current of the motor (60); and A method comprising a step of setting an initial duty ratio command for initiating square wave control based on the d-axis voltage and q-axis voltage of the above motor (60).

14. Motor (60); An inverter (50) that generates an alternating current from a direct current power source and outputs an alternating current driving current to the motor (60); A current sensor (70) that detects the phase current of the above motor (60); A voltage sensor (80) that detects the phase voltage of the above motor (60); A memory (1940) storing at least one instruction; and comprising at least one processor (110), The at least one processor (110) executes the at least one instruction, At the end point of the square wave control, the duty ratio for the inverter control signal that changes the on / off state of multiple switches included in the inverter (50) is calculated, Based on the above inverter control signal, the phase voltage of the motor (60) is calculated, Based on the phase voltage of the above motor (60) and the rotor position of the above motor (60), an initial voltage command is set to initiate sinusoidal control, A home appliance (100), characterized in that the phase voltage of the motor (60) based on the initial voltage command corresponds to the phase voltage of the motor (60) based on the duty ratio.

15. In paragraph 14, The at least one processor (110) executes the at least one instruction, The driving voltage of the motor (60) is detected through the voltage sensor (80), Based on the driving voltage of the above motor (60), the rotation speed of the above motor (60) is detected, A home appliance (100) that calculates the duty ratio to reduce the speed error between the speed command and the rotation speed of the motor (60).

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