Induction heating device and method for controlling induction heating device

Abstract

The present specification relates to an induction heating device and a method for controlling the induction heating device. The induction heating device according to an embodiment may include: an upper plate unit including a heating area and an operation area; a working coil disposed at a position corresponding to the heating area; an inverter including a plurality of switching elements and providing a current to the working coil; a driving circuit for providing a switching signal to each switching element included in the inverter; and a controller for determining a driving frequency of the inverter and providing a control signal based on the driving frequency to the driving circuit so as to drive the working coil.

Description

Induction heating device and control method of induction heating device

[0001] This specification relates to an induction heating device and a control method for the induction heating device.

[0002]

[0003] An induction heating device heats a metal container by generating eddy currents in the container through the magnetic field generated around the working coil. When the device is operated, an alternating current is applied to the working coil. This generates an induced magnetic field around the working coil, which is located within the device. When the magnetic field lines of the induced magnetic field pass through the bottom of the container, which contains a metal component placed above the working coil, an eddy current is generated within the bottom of the container. When the eddy current flows through the container, the container heats.

[0004] When a vessel is heated by an induction heating device, a certain amount of time is required for the load inside the vessel to boil. However, the time it takes for the load to reach the boiling point may vary depending on the type of vessel and the load.

[0005] Several technologies have been proposed to notify users when a load within a vessel heated by an induction heater has reached boiling point. Examples of these conventional technologies include probe-type temperature sensors for measuring the temperature of the load within the vessel. However, probe-type temperature sensors are complex to use, compromise the hygiene of the load within the vessel, and require frequent recharging.

[0006] Another example of a prior art is an induction heating device with a built-in vibration sensor that measures the vibration of the container as the load reaches its boiling point. However, the types of containers for which the induction heating device with a built-in vibration sensor can detect the boiling state of the load are very limited. This inconveniences the user by requiring them to individually check the type of container. Furthermore, if the user does not use an appropriate container, the boiling state of the load may not be detected at all.

[0007]

[0008] The purpose of this specification is to provide an induction heating device and a control method of the induction heating device that can accurately notify a user that a load inside a container has reached a boiling state through simple operation without degrading the hygiene of the load inside the container.

[0009] The purpose of this specification is to provide an induction heating device and a control method of the induction heating device that can accurately notify a user that a load inside a container has reached a boiling state without a separate sensor or component.

[0010] The purpose of this specification is to provide an induction heating device and a control method of the induction heating device that can accurately notify a user when a load inside a container has reached a boiling state for a wider variety of containers.

[0011] The purpose of this specification is to provide an induction heating device and a control method for the induction heating device that can maintain a load in a boiling state without increasing the temperature of the load when the load reaches a boiling state even if the user does not monitor the state of the load.

[0012] The purpose of this specification is not limited to the aforementioned purposes, and other purposes and advantages of this specification not mentioned herein will be more clearly understood by the embodiments of this specification described below. Furthermore, the purposes and advantages of this specification can be realized by the components and combinations thereof described in the claims.

[0013]

[0014] An induction heating device according to one embodiment may include an upper portion including a heating area and an operating area, a working coil disposed at a position corresponding to the heating area, an inverter including a plurality of switching elements and supplying current to the working coil, a driving circuit supplying a switching signal to each switching element included in the inverter, and a controller that determines a driving frequency of the inverter and supplies a control signal based on the driving frequency to the driving circuit to drive the working coil.

[0015] In one embodiment, the controller may receive a load amount of a load within a container provided above the working coil, calculate a heating index of the container, determine an output profile corresponding to the load amount and the heating index, and perform an output control operation for the working coil according to the output profile.

[0016] In one embodiment, the output profile may include a plurality of output control conditions and a power level corresponding to each output control condition.

[0017] In one embodiment, the output control condition may be determined based on at least one of a temperature prediction value for the load and an integrated power value of the working coil.

[0018] In one embodiment, the controller can change the power level of the working coil to a power level corresponding to an output control condition defined in the output profile when the output control condition is satisfied.

[0019] In one embodiment, the controller may reduce the power level of the working coil until an output regulation termination condition defined in the output profile is satisfied.

[0020] In one embodiment, the controller may perform a predetermined output maintenance operation when an output regulation termination condition defined in the output profile is satisfied.

[0021] In one embodiment, when an output regulation termination condition defined in the output profile is satisfied, the power level of the working coil can be maintained at a predetermined power level.

[0022] In one embodiment, the load amount can be entered by a load amount input button placed in the operation area.

[0023] In one embodiment, when the load is input, the heating index may be displayed in the operating area or the heating index may be output as a voice.

[0024] In one embodiment, a method for controlling an induction heating device, comprising: an upper portion including a heating area and an operating area; a working coil disposed at a position corresponding to the heating area; an inverter including a plurality of switching elements and supplying current to the working coil; a driving circuit supplying switching signals to each switching element included in the inverter; and a controller for determining a driving frequency of the inverter and supplying a control signal based on the driving frequency to the driving circuit to drive the working coil, may include a step in which the controller receives an amount of a load of a load in a container provided above the working coil; a step in which the controller calculates a heating index of the container; a step in which the controller determines an output profile corresponding to the amount of load and the heating index; and a step in which the controller performs an output control operation for the working coil according to the output profile.

[0025] In one embodiment, the output profile may include a plurality of output control conditions and a power level corresponding to each output control condition.

[0026] In one embodiment, the output control condition may be determined based on at least one of a temperature prediction value for the load and an integrated power value of the working coil.

[0027] In one embodiment, the step of the controller performing an output control operation for the working coil according to the output profile may include a step of the controller changing a power level of the working coil to a power level corresponding to the output control condition when an output control condition defined in the output profile is satisfied.

[0028] In one embodiment, the step of the controller performing an output regulation operation for the working coil according to the output profile may include the step of reducing a power level of the working coil until an output regulation termination condition defined in the output profile is satisfied.

[0029] In one embodiment, the step of performing an output adjustment operation for the working coil according to the output profile may include a step of performing a predetermined output maintenance operation when an output adjustment termination condition defined in the output profile is satisfied.

[0030] In one embodiment, when an output regulation termination condition defined in the output profile is satisfied, the power level of the working coil can be maintained at a predetermined power level.

[0031] In one embodiment, the load amount can be entered by a load amount input button placed in the operation area.

[0032] In one embodiment, when the load is input, the heating index may be displayed in the operating area or the heating index may be output as a voice.

[0033]

[0034] According to the induction heating device and the control method of the induction heating device of the embodiments, it is possible to accurately notify the user that the load inside the container has reached a boiling state through a simple operation without deteriorating the hygiene of the load inside the container.

[0035] According to the induction heating device and the control method of the induction heating device of the embodiments, it is possible to accurately notify a user that the load inside the container has reached a boiling state without a separate sensor or part.

[0036] According to the induction heating device and the control method of the induction heating device of the embodiments, it is possible to accurately notify a user that the load inside the container has reached a boiling state for more types of containers.

[0037] According to the induction heating device and the control method of the induction heating device of the embodiments, even if the user does not monitor the state of the load, the load can be maintained in a boiling state without increasing the temperature of the load when the load reaches a boiling state, thereby improving safety.

[0038]

[0039] Figure 1 is an exploded perspective view of an induction heating device according to one embodiment.

[0040] Fig. 2 is a circuit diagram of an induction heating device according to one embodiment.

[0041] Fig. 3 shows an operation unit of an induction heating device according to one embodiment.

[0042] FIG. 4 illustrates an example of an output profile for an output control operation of an induction heating device according to one embodiment.

[0043] Fig. 5 is a flowchart showing a control method of an induction heating device according to one embodiment.

[0044] FIG. 6 is a graph showing a load temperature value, a temperature prediction value, an accumulated power value, and a power level when a load inside a container is heated according to a control method of an induction heating device according to one embodiment.

[0045]

[0046] The above-described objects, features, and advantages are described in detail below with reference to the attached drawings, so that those skilled in the art to which the present disclosure pertains can easily practice the embodiments of the present disclosure. In describing the present disclosure, if a detailed description of a known technology related to the present disclosure is determined to unnecessarily obscure the gist of the present disclosure, a detailed description thereof will be omitted. Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the attached drawings. In the drawings, the same reference numerals indicate the same or similar components.

[0047] Figure 1 is an exploded perspective view of an induction heating device according to one embodiment.

[0048] An induction heating device (10) according to one embodiment may include a case (102) forming a main body and a cover plate (104) coupled with the case (102) to seal the case (102).

[0049] The cover plate (104) can be coupled to the upper surface of the case (102) to seal a space formed inside the case (102). The cover plate (104) can include a top portion (106) on which a container for cooking food can be placed. In one embodiment, the top portion (106) can be made of a tempered glass material such as ceramic glass, but the material of the top portion (106) can vary depending on the embodiment.

[0050] The upper portion (106) may be formed with heating areas (12, 14) each corresponding to a working coil assembly (122, 124). In order to enable a user to clearly recognize the location of the heating areas (12, 14), lines or shapes corresponding to the heating areas (12, 14) may be printed or displayed on the upper portion (106).

[0051] The case (102) may have a hexahedral shape with an open top. A working coil assembly (122, 124) for heating a container may be arranged in a space formed inside the case (102). In addition, an interface unit (114) having a function of allowing a user to apply power or adjust the power level of each heating area (12, 14) and a function of displaying information related to the induction heating device (10) may be provided inside the case (102). The interface unit (114) may be formed as a touch panel that allows both information input and information display by touch, but an interface unit (114) having a different structure may be used depending on the embodiment.

[0052] In addition, the upper part (106) may be provided with an operation area (118) positioned corresponding to the interface part (114). For the user's operation, characters or images may be pre-printed on the operation area (118). The user may perform a desired operation by touching a specific point on the operation area (118) with reference to the characters or images pre-printed on the operation area (118). In addition, information output by the interface part (114) may be displayed through the operation area (118).

[0053] The user can set the power level of each heating zone (12, 14) through the interface unit (114). For example, the power level can be displayed as a number (e.g., 1, 2, 3, ..., 9) on the operation area (118). When the power level for each heating zone (12, 14) is set, a target power value of a working coil corresponding to each heating zone (12, 14) and a heating frequency corresponding to the target power value can be determined. The controller can drive each working coil so that the output power value of each working coil matches the target power value set by the user based on the determined heating frequency.

[0054] A power supply unit (112) for supplying power to a working coil assembly (122, 124) or an interface unit (114) can be placed in a space formed inside the case (102).

[0055] For reference, in the embodiment of FIG. 1, two working coil assemblies, i.e., a first working coil assembly (122) and a second working coil assembly (124), are exemplarily illustrated as being arranged inside the case (102), but depending on the embodiment, one working coil assembly or three or more working coil assemblies may be arranged inside the case (102).

[0056] The working coil assembly (122, 124) may include a working coil that forms an induced magnetic field using a high-frequency alternating current supplied by the power supply unit (112) and an insulating sheet for protecting the coil from heat generated by the container. For example, in FIG. 1, the first working coil assembly (122) may include a first working coil (132) and a first insulating sheet (130) for heating a container placed in the first heating area (12). Also, although not shown, the second working coil assembly (124) may include a second working coil and a second insulating sheet. In some embodiments, an insulating sheet may not be disposed on each of the working coil assemblies (122, 124).

[0057] A temperature sensor may be positioned at the center of each working coil. For example, a temperature sensor (134) may be positioned at the center of the first working coil (132) in FIG. 1. The temperature sensor may measure the temperature of a container provided in each heating zone. In one embodiment, the temperature sensor may be a thermistor temperature sensor having a variable resistor whose resistance value changes depending on the temperature of the container, but the type of temperature sensor is not limited thereto.

[0058] In one embodiment, the temperature sensor outputs a sensing voltage corresponding to the temperature of the container, and the sensing voltage output from the temperature sensor can be transmitted to the controller. The controller can determine the temperature of the container based on the magnitude of the sensing voltage output from the temperature sensor, and if the temperature of the container exceeds a predetermined reference value, perform an overheat protection operation to lower the actual power value of the working coil or stop the operation of the working coil.

[0059] Although not shown in Fig. 1, a substrate on which a plurality of circuits or elements, including a controller, are mounted may be placed in a space formed inside the case (102). The controller may drive each working coil to perform a heating operation according to a user's heating start command input through the operation area (118) and the interface unit (114). When the user inputs a heating end command through the operation area (118) and the interface unit (114), the controller may stop driving the working coil to terminate the heating operation.

[0060] Also, although not shown in FIG. 1, a speaker for audio output may be placed in the space formed inside the case (102).

[0061] Fig. 2 is a circuit diagram of an induction heating device according to one embodiment.

[0062] An induction heating device (10) according to one embodiment includes a rectifier circuit (202), a smoothing circuit (203), an inverter (or inverter circuit) (212), a working coil (WC), a controller (2), and a driving circuit (22). The working coil (WC) may be either the first working coil or the second working coil of the embodiment illustrated in FIG. 1.

[0063] The rectifier circuit (202) may include a plurality of diode elements. In one embodiment, the rectifier circuit (202) may be a bridge diode circuit, but depending on the embodiment, the rectifier circuit (202) may be another circuit. The rectifier circuit (202) may rectify an AC input voltage supplied from an external power supply (20) and output a voltage having a pulsating waveform.

[0064] The smoothing circuit (203) can smooth the voltage rectified by the rectifier circuit (202) and output a DC link voltage. The smoothing circuit (203) can include an inductor (L) and a DC link capacitor (CD).

[0065] The inverter (212) may include a first switching element (SW1), a second switching element (SW2), a third switching element (SW3), a fourth switching element (SW4), and a resonant capacitor (CR). The first switching element (SW1) and the second switching element (SW2) are connected in series with each other, and the third switching element (SW3) and the fourth switching element (SW4) are connected in series with each other. The first switching element (SW1) and the second switching element (SW2) are connected in parallel with the third switching element (SW3) and the fourth switching element (SW4). A working coil (WC) is connected between the connection points of the first switching element (SW1) and the second switching element (SW2) and the connection points of the third switching element (SW3) and the fourth switching element (SW4). The resonant capacitor (CR) is connected in series with the working coil (WC). The inverter (212) converts the current output from the smoothing circuit (204) into an alternating current and supplies the converted alternating current to the working coil (WC).

[0066] In one embodiment, the first switching element (SW1) and the second switching element (SW2) can be alternately turned on and off. In addition, the third switching element (SW3) and the fourth switching element (SW4) can be alternately turned on and off. By the alternate turning on and turning off operations, i.e., the switching operations, of the switching elements (SW1, SW2, SW3, SW4) included in the inverter (212), the DC link voltage input to the inverter (212) is converted into an AC current. The AC current converted by the inverter (212) is supplied to each of the working coils (WC). When the AC current is supplied, a resonance phenomenon occurs in the working coil (WC), and a container provided on the upper portion of the working coil (WC) is heated.

[0067] The controller (2) outputs a control signal for controlling the driving circuit (22). The driving circuit (22) supplies switching signals (SS1, SS2, SS3, SS4) to each switching element (SW1, SW2, SW3, SW4) according to the control signal supplied from the controller (2). In the present specification, the first switching signal (SS1), the second switching signal (SS2), the third switching signal (SS3), and the fourth switching signal (SS4) may each be a PWM (Pulse Width Modulation) signal having a predetermined duty cycle.

[0068] When the alternating current output from the inverter (212) is supplied to the working coil (WC), the working coil (WC) is driven. When the working coil (WC) is driven, a container provided on top of the working coil (WC) is heated. The amount of heat energy supplied to the container may vary depending on the amount of power actually generated by driving the working coil (WC), i.e., the output power value of the working coil.

[0069] For example, when a user inputs a power on command through the operation area (118) of the induction heating device (10) to change the induction heating device (10) to a power on state, power is supplied to the induction heating device (10) from an external power supply (20) and the induction heating device (10) enters an operation standby state. Then, the user can input a heating start command by setting a power level for the first heating area (12) and / or the second heating area (14). When the user inputs the heating start command, the controller (2) can determine the required power value of the working coil (WC) corresponding to the power level set by the user.

[0070] The controller (2) that receives the heating start command can determine a frequency corresponding to the required power value of the working coil (WC), i.e., a heating frequency, and supply a control signal corresponding to the determined heating frequency to the driving circuit (22). Accordingly, the working coil (WC) can be driven when the switching signals (SS1, SS2, SS3, SS4) output from the driving circuit (22) are input to the switching elements (SW1, SW2, SW3, SW4), respectively. When the working coil (WC) is driven, a container provided on the upper portion of the working coil (WC) can be heated.

[0071] An induction heating device (10) according to one embodiment may include a shunt resistor (RS1). The shunt resistor (RS1) may be connected between a smoothing circuit (203) and an inverter (212). Depending on the embodiment, the shunt resistor (RS1) may be omitted.

[0072] An induction heating device (10) according to one embodiment may include an input current sensor (31) that senses the magnitude of the current flowing through the shunt resistor (RS1), i.e., the current value. The controller (2) may calculate the magnitude of the current input to the working coil (WC), i.e., the current value, based on the current value sensed through the shunt resistor (RS1).

[0073] In one embodiment, the controller (2) can sense the magnitude of the voltage applied to both ends of the DC link capacitor (CD), i.e., the DC link voltage value, using a voltage sensor (33).

[0074] In one embodiment, the controller (2) can calculate the output power value of the working coil (WC) according to [Mathematical Formula 1].

[0075]

[0076] [Mathematical Formula 1]

[0077] P = V dc I avg

[0078]

[0079] In [Mathematical Formula 1], P represents the output power value of the working coil (WC), Vdc represents the magnitude of the voltage applied to both ends of the DC link capacitor (CD), i.e., the DC link voltage value, and Iavg represents the average value of each current value sensed through the shunt resistor (RS1).

[0080] The method by which the controller (2) calculates the output power value of the working coil (WC) based on [Mathematical Formula 1] is only one example. The controller (2) can calculate the output power value of the working coil (WC) using other known methods.

[0081] In one embodiment, the controller (2) can measure the size of the resonant current generated by the working coil (WC) when the working coil (WC) is driven, i.e., the resonant current value of the working coil (WC), using the resonant current sensor (35). The controller (2) can adjust the output power value of the working coil (WC) based on the resonant current value measured by the resonant current sensor (35).

[0082] Fig. 3 shows an operation unit of an induction heating device according to one embodiment.

[0083] Referring to FIG. 3, the operating unit (118) of the induction heating device according to one embodiment may include a power button (301) and a power lamp (302). A user may input a power-on command by pressing the power button (301) when the induction heating device is in a power-off state. When the power-on command is input, the induction heating device may be switched to a power-on state, and the power lamp (302) may be turned on. A user may input a power-off command by pressing the power button (301) when the induction heating device is in a power-on state. When the power-off command is input, the induction heating device may be switched to a power-off state, and the power lamp (302) may be turned off.

[0084] An operating unit (118) of an induction heating device according to one embodiment may include a first power level display window (311), a first power level adjustment button (312), a second power level display window (321), and a second power level adjustment button (322). A user can input or change the power level of the first working coil through the first power level adjustment button (312).

[0085] When a user inputs or changes the power level of the first working coil through the first power level adjustment button (312), the power level of the first working coil can be displayed in the first power level display window (311). The user can input or change the power level of the second working coil through the second power level adjustment button (322). When a user inputs or changes the power level of the second working coil through the second power level adjustment button (322), the power level of the second working coil can be displayed in the second power level display window (321).

[0086] In one embodiment, the power level of the first working coil and the power level of the second working coil may be set to any one of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, and turbo. As the power level increases, the output power value of each working coil may increase. However, the range and value of the power level of each working coil may be set differently depending on the embodiment.

[0087] When a user inputs a power level from 1 to turbo through the first power level adjustment button (312) or the second power level adjustment button (322), power may be supplied to each working coil, and a heating operation may start. That is, inputting a power level from 1 to turbo through the first power level adjustment button (312) or the second power level adjustment button (322) may be equivalent to inputting a heating start command. When a user inputs a power level of 0 through the first power level adjustment button (312) or the second power level adjustment button (322), power may be cut off to each working coil, and a heating operation may end. That is, inputting a power level of 0 through the first power level adjustment button (312) or the second power level adjustment button (322) may be equivalent to inputting a heating end command.

[0088] An operation unit (118) of an induction heating device according to one embodiment may include a first timer display window (313), a second timer display window (323), and timer adjustment buttons (303, 304). When each working coil is driven, a user can input or change the driving time of each working coil in a predetermined unit (e.g., in minutes) through the timer adjustment buttons (303, 304). The user can decrease the driving time through the timer decrease button (303) or increase the driving time through the timer increase button (304).

[0089] When a user inputs the driving time of each working coil, the driving time of each working coil can be displayed in the first timer display window (313) or the second timer display window (323). The driving time displayed in the first timer display window (313) or the second timer display window (323) can decrease until it becomes 0. When the driving time displayed in the first timer display window (313) or the second timer display window (323) becomes 0, the driving of the working coil can be terminated.

[0090] An operation unit (118) of an induction heating device according to one embodiment may include load input buttons (331, 332, 333) and load display lamps (341, 342, 343). A user may input the capacity or volume of a load inside a container, i.e., the load amount, through the load input buttons (331, 332, 333). When a user inputs a load amount by pressing any one of the load input buttons (331, 332, 333), a lamp corresponding to the load amount pressed by the user among the load display lamps (341, 342, 343) may light up.

[0091] In FIG. 3, three load input buttons (331, 332, 333) corresponding to load amounts of 0.5 L, 1.0 L, and 1.5 L are illustrated as an example, but the number of load input buttons and the numerical value of the load amount assigned to each load input button may vary depending on the embodiment.

[0092] In another embodiment, each load input button (331, 332, 333) may be assigned a different number, letter, and unit to indicate the capacity of the load. For example, each load input button (331, 332, 333) may be assigned a number and unit (e.g., 0.2 kg, 0.5 kg, 1.0 kg) indicating the mass of the load. In another example, each load input button (331, 332, 333) may be assigned a letter or number (e.g., small, medium, large or 1, 2, 3) indicating the relative capacity of the load.

[0093] In another embodiment, the induction heating device (10) may include a voice input device (e.g., a microphone) for receiving a user's voice input. The user may also input the load capacity by voice through the voice input device instead of the load capacity input buttons (331, 332, 333).

[0094] In another embodiment, a fine volume adjustment button (not shown) may be arranged on one side of the load input buttons (331, 332, 333). The user can adjust the load more precisely by pressing the fine volume adjustment button. For example, if the user presses the load input button (331) to input the load as 0.5 L and then presses the fine volume decrease button, the load may be decreased by a predetermined unit volume (e.g., 0.1 L), and if the fine volume increase button is pressed, the load may be increased by a predetermined fine adjustment volume (e.g., 0.1 L). The size of the unit volume assigned to the fine volume adjustment button may vary depending on the embodiment.

[0095] Hereinafter, an exemplary process of heating a container placed in a first heating area (12) of an induction heating device according to one embodiment is described with reference to FIGS. 1 to 3.

[0096] In one embodiment, a user may provide a container containing a load to the first heating zone (12) and press a power button (301) to turn the induction heating device (10) on.

[0097] In one embodiment, the controller (2) can calculate a heating index of a container provided on top of the first working coil (132) while driving the first working coil (132) at a predetermined target power value. For example, the heating index of the container can be defined as in [Mathematical Formula 2] below.

[0098]

[0099] [Equation 2]

[0100] PEI = PR / PC

[0101] (Here, PEI is the heating index, PR is the output power value of the first working coil (132), and PC is the target power value of the first working coil (132))

[0102]

[0103] The controller (2) can control the driving circuit (22) so that power is supplied to the first working coil (132) based on a predetermined target power value (PC). When power is supplied to the first working coil (132) and the first working coil (132) is driven, the controller (2) can calculate the output power value (PR) of the first working coil (132). The controller (2) can substitute the target power value (PC) and the output power value (PR) of the first working coil (132) into [Mathematical Formula 2] to calculate the heating index (PEI) of the container provided on the upper portion of the first working coil (132).

[0104] In one embodiment, the heating index (PEI) of the container may be expressed as a number between 0 and 10. However, the range and value of the heating index (PEI) may be set differently depending on the embodiment. The higher the heating index (PEI), the higher the heating efficiency of the container relative to the power consumed and the lower the power loss. Additionally, the higher the heating index (PEI), the faster the load inside the container can be heated.

[0105] When a container is provided on top of the first working coil (132), the user can input the load amount (0.5 L) of the load in the container by pressing the first load amount input button (331) among the load amount input buttons (331, 332, 333). If the container is not provided on top of the first working coil (132) when the user presses one of the load amount input buttons (331, 332, 333), a predetermined alarm operation (e.g., voice output through a speaker and / or display of a specific character (e.g., “u”) on the first power level display window (311)) may be performed, and the output control operation described below may not be performed. In another embodiment, when the container is not provided on top of the first working coil (132), a voice for notifying the absence of the container may be output through the speaker of the induction heating device (10).

[0106] When a user inputs a load by pressing the first load input button (331) while a container is provided on top of the first working coil (132), a heating index (e.g., “8”) of the container provided on top of the first working coil (132) may be displayed on the first timer display window (313). In addition, when the user inputs the load, a letter (e.g., “A”) may be displayed on the first power level display window (311) to indicate that the induction heating device (10) is driven in an automatic mode in which the output of the first working coil (132) is automatically controlled.

[0107] In the present specification, when the induction heating device (10) is driven in the "automatic mode", heating of the container begins without the user inputting a power level, and the power level of the working coil can be automatically adjusted through the output control operation until the load inside the container reaches a boiling state. In addition, when the load inside the container reaches a boiling state, the power level of the working coil can be maintained at a predetermined power level. In the present specification, when the induction heating device (10) is driven in the "manual mode", the user must input the power level of each working coil through the power level control buttons (312, 322) to begin the heating operation of the working coil, and the power levels of the working coils are not automatically adjusted.

[0108] In one embodiment, when a user inputs a load by pressing the first load input button (331), a heating index (e.g., “8”) displayed on the first timer display window (313), a character (e.g., “A”) indicating an automatic mode displayed on the first power level display window (311), and the first load display lamp (331) may each blink for a predetermined time (e.g., 5 seconds). While the first load display lamp (331) blinks, the first working coil (132) is not driven, and the user may change the load by pressing another load input button (332, 333).

[0109] In one embodiment, when a container is provided on top of the first working coil (132), and the user presses any one of the load input buttons (331, 332, 333), the controller (2) may compare the heating index (PEI) of the container with a predetermined reference index (e.g., 7). If the comparison result shows that the heating index (PEI) of the container is less than the reference index, a predetermined alarm operation may be performed, and the output control operation described below may not be performed. For example, if the heating index (PEI) of the container is less than the reference index, a voice such as “Please check the heating index” or “Please check the size or material of the container” may be output through the speaker of the induction heating device (10).

[0110] If the comparison result shows that the heating index (PEI) of the container is greater than or equal to the reference index, the output control operation described below can be performed.

[0111] When a predetermined time (e.g., 5 seconds) has elapsed since the user pressed the first load input button (331), an output control operation may be initiated. When the output control operation is initiated, a letter (e.g., "A") indicating an automatic mode displayed on the first power level display window (311) and the first load display lamp (331) may change from a blinking state to a lit state. In addition, when the output control operation is initiated, a heating index (e.g., "8") may not be displayed on the first timer display window (313).

[0112] In one embodiment, the controller (2) can determine an output profile corresponding to the load amount and the heating index of the container input by the user. The output profile can be stored in advance in a storage unit (not shown).

[0113] FIG. 4 illustrates an example of an output profile for an output control operation of an induction heating device according to one embodiment.

[0114] Figure 4 illustrates a number of output profiles selected based on a user-entered load.

[0115] The controller (2) can select one of a plurality of output profiles based on the load amount input by the user. More specifically, the controller (2) can determine which range of the load amount range defined for each output profile illustrated in Fig. 4 the user input amount falls within, and select an output profile based on the determination result.

[0116] For example, if the load amount input by the user is 0.5 L, the controller (2) can select the first output profile. As another example, if the load amount input by the user is 1.3 L, the controller (2) can select the third output profile.

[0117] The load range defined for each output profile may be set differently depending on the embodiment. In addition, the number of output profiles may vary depending on the embodiment.

[0118] As described above, since the output control operation is performed only when the heating index of the container is equal to or greater than a predetermined reference index (e.g., 7), the output profile of FIG. 4 may only include heating indices (10, 9, 8, 7) of the container for which the output control operation can be performed. However, the range and numerical value of the heating index of the container included in the output profile may vary depending on the embodiment.

[0119] Additionally, the output profile of FIG. 4 may include multiple output control points (S0, S1, S2, S3). For example, the output control points may include an output control start point (S0), a first output control point (S1), a second output control point (S2), and an output control end point (S3). The number of output control points may be set differently depending on the embodiment.

[0120] Additionally, the output profile of FIG. 4 may include output control conditions corresponding to each output control point (S1, S2, S3).

[0121] In one embodiment, the output control condition can be set based on at least one of a temperature prediction value and an integrated power value.

[0122] In this specification, the temperature prediction value means the temperature value of the load inside the container predicted or estimated by the controller (2) at a specific point in time when the container is heated. For example, the controller (2) can generate a predicted value for the temperature of the load inside the container as a temperature prediction value by using a temperature prediction model generated in advance through machine learning when the container is heated. The input factors of the temperature prediction model used at this time may include the amount of load, the output power value of the working coil, the heating time, etc., but the input factors used in the temperature prediction model are not limited thereto, and various other input factors may be used to estimate the temperature value of the load inside the container depending on the embodiment. In addition, a different temperature prediction model may be used to generate the temperature prediction value depending on the embodiment.

[0123] In this specification, the accumulated power value refers to a value calculated by accumulating the output power value of the working coil, measured from the time when the driving of the working coil begins, by a predetermined time unit. In other words, the accumulated power value refers to the amount of power consumed by the working coil from the time when the driving of the working coil begins to a specific time point.

[0124] For example, if the load input by the user is 0.6 L, the controller (2) can select the first output profile among the output profiles shown in Fig. 4. The output control conditions of the first output profile can be set as follows, for example.

[0125] AA1: The predicted temperature is 85℃ and the accumulated power is 1440W.

[0126] AA2: The predicted temperature is 90℃ and the accumulated power is 1570W.

[0127] AA3: The predicted temperature is 98℃ and the accumulated power is 1689W.

[0128] When the driving of the working coil and heating of the container begin at the output control start time (S0), the controller (2) can calculate the temperature prediction value and the accumulated power value at predetermined time units (e.g., 1 second).

[0129] The controller (2) can determine whether each output control point (S1, S2, S3) is reached by referring to the first output profile. Accordingly, the point in time when the temperature prediction value reaches 85°C and the integrated power value reaches 1440 W during the container heating process becomes the first output control point (S1). In addition, the point in time when the temperature prediction value reaches 90°C and the integrated power value reaches 1570 W becomes the second output control point (S2). In addition, the point in time when the temperature prediction value reaches 98°C and the integrated power value reaches 1689 W becomes the output control end point (S3). The output control condition corresponding to the output control end point (S3) may also be referred to as an output control end condition.

[0130] However, the output control conditions for defining the output control point may be set differently depending on the embodiment. For example, the output control conditions may be set solely based on the temperature prediction value or solely based on the integrated power value. In other embodiments, the output control conditions may be defined by values ​​other than the temperature prediction value or the integrated power value.

[0131] For example, if the load amount input by the user is 0.9 L, the controller (2) can select the second output profile among the output profiles shown in Fig. 4. The output control conditions of the second output profile can be set as follows, for example.

[0132] BB1: Temperature prediction is 85℃

[0133] BB2: The temperature prediction is 90℃

[0134] BB3: The temperature prediction is 98℃

[0135] When the driving of the working coil and heating of the container begin at the output control start time (S0), the controller (2) can produce a temperature prediction value at predetermined time units (e.g., 1 second).

[0136] The controller (2) can determine whether each output control point (S1, S2, S3) is reached by referring to the second output profile. Accordingly, the point in time when the temperature prediction value reaches 85°C during the container heating process becomes the first output control point (S1). In addition, the point in time when the temperature prediction value reaches 90°C becomes the second output control point (S2). In addition, the point in time when the temperature prediction value reaches 98°C becomes the output control end point (S3). The output control condition corresponding to the output control end point (S3) may also be referred to as the output control end condition.

[0137] As another example, if the load input by the user is 1.0 L, the controller (2) can select the second output profile among the output profiles shown in Fig. 4. The output control conditions of the second output profile can be set as follows, for example.

[0138] BB1: The accumulated power value is 2400W

[0139] BB2: The accumulated power value is 2800W

[0140] BB3: The accumulated power value is 3133W

[0141] When the driving of the working coil and heating of the container begin at the output control start time (S0), the controller (2) can produce a temperature prediction value at predetermined time units (e.g., 1 second).

[0142] The controller (2) can determine whether each output control point (S1, S2, S3) is reached by referring to the second output profile. Accordingly, the point in time when the accumulated power value reaches 2400 W during the container heating process becomes the first output control point (S1). In addition, the point in time when the accumulated power value reaches 2800 W becomes the second output control point (S2). In addition, the point in time when the accumulated power value reaches 3133 W becomes the output control end point (S3). The output control condition corresponding to the output control end point (S3) may also be referred to as the output control end condition.

[0143] In addition, each output profile in FIG. 4 may include a power level of the working coil according to a combination of the heating index of the container and the output control points (S0, S1, S2, S3). For example, when the heating index of the container is 10 and the load amount input by the user is 0.5 L, the controller (2) may adjust or change the power level of the working coil to the power levels (9, 8, 6, 6) recorded in the first output profile of FIG. 4 for each output point (S0, S1, S2, S3). The heating index defined in each output profile and the power level corresponding to each output control point may be set differently depending on the embodiment.

[0144] In one embodiment, whenever at least one of the respective output control points (S0, S1, S2, S3) is reached, a voice may be output through a speaker included in the induction heating device (10) to notify the user of the arrival of each output control point (S0, S1, S2, S3). For example, when the output control point (S2) is reached during the container heating process, a voice such as “The heat is adjusted so that the food does not overflow” may be output through the speaker of the induction heating device (10). As another example, when the output control end point (S3) is reached during the container heating process, a voice such as “The food is boiling, so the smart heating operation is ended” may be output through the speaker of the induction heating device (10).

[0145] An example of an output control operation performed by the controller (2) according to the output profile illustrated in Fig. 4 is as follows. When a user provides a container with a load on the first working coil (132), the user presses the second load input button (332) to input the load amount (1.0 L) of the container. Then, the controller (2) calculates the heating index of the container provided on the first working coil (132).

[0146] Here, the output control conditions of the second output profile can be defined as follows.

[0147] BB1: The predicted temperature is 85℃ and the accumulated power is 240W.

[0148] BB2: The predicted temperature is 90℃ and the accumulated power is 2800W.

[0149] BB3: The predicted temperature is 98℃ and the accumulated power is 3133W.

[0150] Assuming that the generated heating index is 8, the controller (2) performs an output control operation according to the second output profile illustrated in Fig. 4. The controller (2) first sets the power level of the first working coil (132) to a power level (9) corresponding to the output control start time (S0) of the output profile. Accordingly, the first working coil (132) is driven to output an output power value corresponding to the set power level (9), thereby starting heating of the container.

[0151] When the output control operation is initiated and the container is heated, the controller (2) calculates a temperature prediction value and an integrated power value at predetermined time units (e.g., 1 second). When the calculated temperature prediction value reaches 85°C and the integrated power value reaches 2400W, the controller (2) changes the power level of the first working coil (132) to 8. After the power level is changed to 8, when the calculated temperature prediction value reaches 90°C and the integrated power value reaches 2800W, the controller (2) changes the power level of the first working coil (132) to 6.

[0152] When the temperature prediction value calculated after the power level is changed to 6 reaches 98°C and the accumulated power value reaches 3133 W, that is, when the output regulation termination condition is satisfied (output regulation termination time point (S3)), the controller (2) terminates the output regulation operation while maintaining the power level of the first working coil (132) at 6.

[0153] That is, the controller (2) can reduce the power level of the working coil until the output regulation termination condition defined in the output profile is satisfied.

[0154] When the output regulation termination condition is satisfied, the controller (2) can perform a predetermined output maintenance operation.

[0155] In one embodiment, the output maintenance action may include a predefined alarm action (e.g., an audio output through a speaker, a boil-over notification message or audio output through an application associated with the induction heating device).

[0156] In another embodiment, the output maintenance operation may include an operation of maintaining the power level of the working coil at a power level corresponding to the output regulation end point (S3) defined in the output profile. For example, in the above-described embodiment, when the output maintenance operation is performed, the power level of the first working coil (132) may be maintained at 6. Accordingly, the load inside the container provided on the first working coil (132) may be maintained in a boiling state.

[0157] In another embodiment, the output maintenance operation may include an operation of displaying the power level of the working coil in a power level display window (311, 321) of the operating area (118). For example, in the embodiment described above, when the output maintenance operation is performed, the first power level display window (311) may display 6, which is the current power level of the first working coil (132), instead of the letter (“A”) indicating the automatic mode.

[0158] In another embodiment, the output maintenance operation may include an operation in which the load indication lamps (341, 342, 343) are turned off. For example, in the embodiment described above, when the output maintenance operation is performed, the second load indication lamp (342) corresponding to the second load input button (332) may be turned off.

[0159] Fig. 5 is a flowchart showing a control method of an induction heating device according to one embodiment.

[0160] A controller (2) of an induction heating device (10) according to one embodiment can input a load amount of a load inside a container provided on top of a working coil (502). In one embodiment, the load amount can be input by a load amount input button (331, 332, 333) arranged in an operation area (118).

[0161] Next, the controller (2) can calculate the heating index of the container provided on the working coil (504). In one embodiment, the controller (2) can calculate the heating index of the container according to [Mathematical Formula 2].

[0162] In one embodiment, when a load amount is input by a user, a heating index may be displayed in the operation area (118). In another embodiment, when a load amount is input by a user, a heating index may be output audibly through a speaker.

[0163] Next, the controller (2) can determine an output profile corresponding to the load input by the user and the previously calculated heating index.

[0164] In one embodiment, the output profile may include a plurality of output control conditions and a power level corresponding to each output control condition.

[0165] In one embodiment, the output control condition may be determined based on at least one of a temperature prediction value for the load and an integrated power value of the working coil.

[0166] Next, the controller (2) can perform an output control operation for the working coil according to the determined output profile.

[0167] In one embodiment, the step of the controller (2) performing an output control operation for the working coil according to the output profile may include a step of the controller (2) changing the power level of the working coil to a power level corresponding to the output control condition when an output control condition defined in the output profile is satisfied.

[0168] In one embodiment, the step of the controller (2) performing an output regulation operation on the working coil according to the output profile may include a step of reducing the power level of the working coil until an output regulation termination condition defined in the output profile is satisfied.

[0169] In one embodiment, the step of the controller (2) performing an output adjustment operation for the working coil according to the output profile may include a step of performing a predetermined output maintenance operation when an output adjustment termination condition defined in the output profile is satisfied.

[0170] In one embodiment, the load within the vessel may be maintained in a boiling state when an output regulation termination condition defined in the output profile is satisfied.

[0171] FIG. 6 is a graph showing a load temperature value, a temperature prediction value, an accumulated power value, and a power level when a load inside a container is heated according to a control method of an induction heating device according to one embodiment.

[0172] In the embodiment of Fig. 6, a cast iron vessel containing 500 mL of water and having a heating index of 9 was heated by an induction heating device. Furthermore, in the embodiment of Fig. 6, the induction heating device was operated in an automatic mode based on an output profile including three output control conditions and three output control points (S0, S1, S2) corresponding to each output control condition.

[0173] FIG. 6 shows temperature value data (61) of the load inside the container measured when the induction heating device is driven in automatic mode under the conditions described above, upper limit data (62) and lower limit data (63) of the temperature prediction value calculated by the induction heating device, accumulated power value data (64) of the working coil calculated by the induction heating device, and a power level (65) of the working coil set by the induction heating device based on the output profile, respectively.

[0174] Referring to Fig. 6, the controller (2) of the induction heating device starts heating the container by setting the power level (65) of the working coil to 9 at the output regulation start point (S0).

[0175] The controller (2) can continuously produce temperature prediction values ​​(upper limit value (62) and lower limit value (63)) using a temperature prediction model generated in advance through machine learning while the container is being heated. For example, the controller (2) can use the upper limit value (62), the lower limit value (63) of the temperature prediction values, or the median or average value of the upper limit value (62) and the lower limit value (63) as temperature prediction values ​​for output control.

[0176] Additionally, the controller (2) can continuously calculate the accumulated power value (64) by accumulating the power consumption of the working coil while the container is heated.

[0177] If the temperature prediction value (63) and the integrated power value (64) satisfy the first output control condition recorded in the output profile, the controller (2) can change the power level of the working coil to 8 (first output control time point (S1)). In addition, if the temperature prediction value (63) and the integrated power value (64) satisfy the output control end condition recorded in the output profile, the controller (2) can change the power level of the working coil to 7 (output control end time point (S2)).

[0178] According to the control process illustrated in Fig. 6, the load within the container can be automatically and rapidly heated in each output control section (S0 to S1, S1 to S2). In addition, after the output control end point (S2), the power level of the working coil is maintained constant, and accordingly, the temperature of the load within the container can also be maintained constant.

[0179] When the induction heating device according to the above-described embodiments is operated in automatic mode, heating of the container begins simply by inputting a load amount without the user having to set a power level, and the power level of the working coil automatically decreases until the load inside the container reaches a boiling state. Furthermore, when the load inside the container reaches a boiling state, the power level of the working coil can be maintained constant so that the power level of the working coil no longer increases and the load remains in a boiling state.

[0180] Additionally, the induction heating device according to the embodiments can notify the user that the load is in a boiling state through a predetermined alarm action (e.g., a voice output through a speaker, a boiling notification message or voice output through an application linked to the induction heating device) when the load inside the container reaches a boiling state. Therefore, the user can easily recognize that the load is in a boiling state even without monitoring the heating process of the container.

[0181] Although the present specification has been described with reference to the drawings exemplified above, the present specification is not limited to the embodiments and drawings disclosed herein, and various modifications may be made by those skilled in the art. Furthermore, even if the effects resulting from the configuration of the present specification have not been explicitly described and explained while describing the embodiments of the present specification, the effects predictable by the corresponding configuration should also be acknowledged.

Claims

1. Top plate including heating zone and operating zone; A working coil positioned corresponding to the above heating area; An inverter comprising a plurality of switching elements and supplying current to the working coil; A driving circuit that supplies a switching signal to each switching element included in the above inverter; and A controller is included that determines the driving frequency of the inverter and supplies a control signal based on the driving frequency to the driving circuit to drive the working coil. The above controller Inputting the load amount of the load in the container provided on the upper part of the working coil, calculating the heating index of the container, determining the output profile corresponding to the load amount and the heating index, and performing an output control operation for the working coil according to the output profile. Induction heating device.

2. In paragraph 1, The above output profile is Containing a plurality of output control conditions and a power level corresponding to each output control condition. Induction heating device.

3. In paragraph 2, The above output control conditions are Determined based on at least one of the temperature prediction value for the above load and the accumulated power value of the working coil. Induction heating device.

4. In paragraph 1, The above controller When the output control condition defined in the above output profile is satisfied, the power level of the working coil is changed to a power level corresponding to the output control condition. Induction heating device.

5. In paragraph 1, The above controller Reduce the power level of the working coil until the output regulation termination condition defined in the above output profile is satisfied. Induction heating device.

6. In paragraph 1, The above controller When the output control termination condition defined in the above output profile is satisfied, a predetermined output maintenance operation is performed. Induction heating device.

7. In paragraph 6, When the output regulation termination condition defined in the above output profile is satisfied, the power level of the working coil is maintained at a predetermined power level. Induction heating device.

8. In paragraph 1, The above load is Input by the load input button placed in the above operation area Induction heating device.

9. In paragraph 1, When the above load amount is input, the heating index is displayed in the operation area or the heating index is output as a voice. Induction heating device.

10. A method for controlling an induction heating device, comprising: an upper portion including a heating area and an operating area; a working coil arranged at a position corresponding to the heating area; an inverter including a plurality of switching elements and supplying current to the working coil; a driving circuit supplying a switching signal to each switching element included in the inverter; and a controller determining a driving frequency of the inverter and supplying a control signal based on the driving frequency to the driving circuit to drive the working coil. A step for receiving a load amount of a load within a container provided on top of the working coil by the controller; A step in which the controller calculates a heating index of the container; a step of the controller determining an output profile corresponding to the load amount and the heating index; and The above controller comprises a step of performing an output control operation for the working coil according to the output profile. A method for controlling an induction heating device.

11. In paragraph 10, The above output profile is Containing a plurality of output control conditions and a power level corresponding to each output control condition. A method for controlling an induction heating device.

12. In paragraph 11, The above output control conditions are Determined based on at least one of the temperature prediction value for the above load and the accumulated power value of the working coil. A method for controlling an induction heating device.

13. In paragraph 10, The step of the above controller performing an output control operation for the working coil according to the above output profile A step of changing the power level of the working coil to a power level corresponding to the output control condition when the output control condition defined in the output profile is satisfied. A method for controlling an induction heating device.

14. In paragraph 10, The step of the above controller performing an output control operation for the working coil according to the above output profile A step of reducing the power level of the working coil until an output regulation termination condition defined in the above output profile is satisfied. A method for controlling an induction heating device.

15. In paragraph 10, The step of the above controller performing an output control operation for the working coil according to the above output profile Including a step of performing a predetermined output maintenance operation when an output control termination condition defined in the above output profile is satisfied. A method for controlling an induction heating device.

16. In paragraph 10, When the output regulation termination condition defined in the above output profile is satisfied, the power level of the working coil is maintained at a predetermined power level. A method for controlling an induction heating device.

17. In paragraph 10, The above load is Input by the load input button placed in the above operation area A method for controlling an induction heating device.

18. In paragraph 10, When the above load amount is input, the heating index is displayed in the operation area or the heating index is output as a voice. A method for controlling an induction heating device.

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