Induction heating device

Abstract

An induction heating apparatus includes: a power supply module having a first terminal and a second terminal; an inductor connected between the first terminal and the first node; a first switching element connected between the first node and the second node; a first switching element connected between the first node and the second node; a first anti-parallel diode connected to the first switching element; a second switching element connected between the first node and a ground node; a second anti-parallel diode connected to the second switching element; a first diode having a cathode connected to the second node and an anode connected to the second terminal; a second diode having a cathode connected to the second terminal and an anode connected to the ground node; a first capacitor connected to the second node and the third node; a second capacitor connected to the third node and a ground node; a third capacitor connected to the second node and a ground node; and a heating coil connected between the first node and the third node.

Description

Technical Field

[0001] The present disclosure relates to an induction heating device having an improved circuit configuration. Background Art

[0002] Generally speaking, an induction heating device is a cooking device that uses the principle of induction heating to heat and cook food. The induction heating device includes a cooking plate on which a cooking container is placed and a heating coil that generates a magnetic field when an electric current is applied.

[0003] When current is applied to the heating coil and a magnetic field is generated, a secondary current is induced in the cooking container, and Joule heat is generated by the resistance component of the cooking container itself. Therefore, the cooking container is heated by the high-frequency current, and the food contained in the cooking container is cooked.

[0004] Induction heating devices that use the cooking container itself as a heat source have a higher heat transfer rate than gas stoves or kerosene stoves that burn fossil fuels and heat the cooking container by the heat of the combustion, so no harmful gases are generated and there is no risk of fire. Summary of the invention

[0005] An aspect of the present disclosure provides an induction heating device with improved performance.

[0006] An induction heating device according to one aspect of an embodiment of the present disclosure includes: a first node, a second node and a third node; a power module having a first terminal and a second terminal; an inductor connected between the first terminal and the first node; a first switching element connected between the first node and the second node; a first reverse parallel diode connected to the first switching element; a second switching element connected between the first node and a ground node; a second reverse parallel diode connected to the second switching element; a first diode having a first cathode connected to the second node and a first anode connected to the second terminal; a second diode having a second cathode connected to the second terminal and a second anode connected to the ground node; a first capacitor connected to the second node and a third node; a second capacitor connected to the third node and the ground node; a third capacitor connected to the second node and the ground node; and a heating coil connected between the first node and the third node.

[0007] The induction heating device may further include: a current sensor connected between the first node and the third node.

[0008] The induction heating device may further include: a resistor connected between the first node and the third node.

[0009] The power module may include an alternating current (AC) power source and a filter configured to remove noise components included in the AC power source.

[0010] The induction heating device may further include a controller configured to control the first switching element and the second switching element.

[0011] The controller may be configured to perform: a first operation of turning off the first switching element and turning on the second switching element; a second operation of turning off the first switching element and the second switching element; and a third operation of turning on the first switching element and turning off the second switching element.

[0012] The controller may be configured to repeatedly perform a sequence of the second operation, the first operation, the third operation, and the second operation.

[0013] The first period of the first operation and the third period of the third operation may both be longer than the second period of the second operation.

[0014] Based on the start of the heating operation, the controller can be configured to maintain the first switching element and the second switching element in the off state for a predetermined time, and in response to applying a positive voltage to the first terminal while the first switching element and the second switching element are maintained in the off state, the input current flows sequentially through the first terminal, the inductor, the first reverse-parallel diode, the third capacitor and the second diode, and reaches the second diode.

[0015] Based on the start of the heating operation, the controller can be configured to maintain the first switching element and the second switching element in the off state for a predetermined time, and in response to applying a negative voltage to the first terminal while the first switching element and the second switching element are maintained in the off state, the input current flows sequentially through the second terminal, the first diode, the third capacitor, the second reverse-parallel diode and the inductor to reach the second diode.

[0016] While applying a positive voltage to the first terminal and performing the first operation, the input current can flow sequentially through the first terminal, the inductor, the second switching element, and the second diode to reach the second terminal, and the resonant current can flow sequentially through the third node, the heating coil, and the second switching element to reach the ground node.

[0017] While applying a positive voltage to the first terminal and performing the second operation, the input current can flow sequentially through the first terminal, the inductor, the first reverse-parallel diode, the third capacitor and the second diode to reach the second terminal, and the resonant current can flow sequentially through the third node, the heating coil and the first reverse-parallel diode to reach the second node.

[0018] While applying a positive voltage to the first terminal and performing the third operation, the input current can flow sequentially through the first terminal, the inductor, the heating coil, the second capacitor, and the second diode to reach the second terminal, and the resonant current can flow sequentially through the second node, the first switching element, and the heating coil to reach the third node.

[0019] While a positive voltage is applied to the first terminal and the third operation is performed, in a state where the input current may not flow, the resonant current may sequentially flow through the second node, the first switching element, and the heating coil to reach the third node.

[0020] While applying a positive voltage to the first terminal and performing the second operation, the input current can flow sequentially through the first terminal, the inductor, the heating coil, the first capacitor, the third capacitor, and the second diode to reach the second terminal, and the resonant current can flow sequentially through the ground node, the second switching element, and the heating coil to reach the third node.

[0021] While a negative voltage is applied to the first terminal and the first operation is performed, the input current can flow sequentially through the second terminal, the first diode, the first capacitor, the heating coil and the inductor to reach the first terminal, and the resonant current can flow sequentially through the third node, the heating coil and the second switching element to reach the ground node.

[0022] While a negative voltage is applied to the first terminal and the first operation is performed, in a state where the input current may not flow, the resonant current may sequentially flow through the third node, the heating coil, and the second switching element to reach the ground node.

[0023] While a negative voltage is applied to the first terminal and the second operation is performed, the input current can flow sequentially through the second terminal, the first diode, the first capacitor, the heating coil and the inductor to reach the first terminal, and the resonant current can flow sequentially through the third node, the heating coil and the first switching element to reach the second node.

[0024] While applying a negative voltage to the first terminal and performing the third operation, the input current can flow sequentially through the second terminal, the first diode, the first switching element and the inductor to reach the first terminal, and the resonant current can flow sequentially through the second node, the first switching element and the heating coil to reach the third node.

[0025] While a negative voltage is applied to the first terminal and the second operation is performed, the input current can flow sequentially through the second terminal, the first diode, the third capacitor, the second reverse-parallel diode and the inductor to reach the first terminal, and the resonant current can flow sequentially through the ground node, the second reverse-parallel diode and the heating coil to reach the third node.

[0026] According to an aspect of the present disclosure, noise generated during operation of an induction heating device may be suppressed.

[0027] According to an aspect of the present disclosure, heating performance of a small cooking container or a cooking container formed of a material having low magnetic permeability may be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a diagram showing the appearance of an induction heating device according to an embodiment.

[0029] Figure 2 and Figure 3 is a diagram for describing a heating principle of an induction heating device according to an exemplary embodiment.

[0030] Figure 4 is a block diagram showing a configuration of an induction heating device according to an embodiment.

[0031] Figure 5 is a diagram showing an example of a coil driving circuit according to an embodiment.

[0032] Figure 6 is a graph showing a change in current over time according to operations of a first switching element and a second switching element when a positive voltage is applied to a first terminal.

[0033] Figure 7 is a graph showing a change in current over time according to operations of a first switching element and a second switching element when a negative voltage is applied to a first terminal.

[0034] Figure 8 is a diagram schematically showing the flow of current when a positive voltage is applied to the first terminal in a state where the first switching element and the second switching element are in an off state.

[0035] Fig. 9 is a diagram schematically showing a flow of current when a negative voltage is applied to the first terminal in a state where the first switching element and the second switching element are in an off state.

[0036] Fig.10 It is schematically shown Figure 6 Diagram of the current flow in the first mode.

[0037] Fig.11 It is schematically shown Figure 6 FIG. 1 is a diagram of the current flow in the second mode.

[0038] Fig.12 It is schematically shown Figure 6 FIG. 5 is a diagram of the current flow in the third mode.

[0039] Fig.13 It is schematically shown Figure 6 FIG. 4 is a diagram of the current flow in the fourth mode.

[0040] Fig.14 It is schematically shown Figure 6 FIG. 5 is a diagram of the current flow in the fifth mode.

[0041] Fig.15 It is schematically shown Figure 7 FIG. 1 is a diagram of the current flow in the sixth mode.

[0042] Fig.16 It is schematically shown Figure 7 Diagram of the current flow in the seventh mode.

[0043] Fig.17 It is schematically shown Figure 7 Diagram of the current flow in the eighth mode.

[0044] Fig.18 It is schematically shown Figure 7 Diagram of the current flow in the ninth mode.

[0045] Fig.19 It is schematically shown Figure 7 Diagram of the current flow in the tenth mode. DETAILED DESCRIPTION

[0046] The embodiments described in this specification and the configurations shown in the drawings are merely examples of preferred embodiments of the present disclosure, and various modifications may be made to replace the embodiments of this specification and the drawings at the time of filing the present disclosure.

[0047] The terms used herein are for the purpose of describing the embodiments and are not intended to limit and / or restrict the present disclosure.

[0048] For example, a singular expression herein may include a plural expression unless the context clearly dictates otherwise.

[0049] In addition, the terms “including” and “having” are intended to indicate the presence of the features, numbers, steps, operations, elements, parts, or a combination thereof described in the specification, and do not exclude the presence or addition of one or more other features, numbers, steps, operations, elements, parts, or a combination thereof.

[0050] It should be understood that although the terms "first", "second", etc. may be used herein to describe various components, these components should not be limited by these terms. These terms are only used to distinguish components from each other.

[0051] Terms such as "~component", "~device", "~block", "~member", "~module" and the like may refer to a unit for processing at least one function or action. For example, these terms may refer to at least one process processed by at least one hardware (e.g., field programmable gate array (FPGA) / application specific integrated circuit (ASIC)), software stored in a memory, or a processor.

[0052] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The same symbols or numerals in the drawings of the present disclosure represent components or elements configured to perform substantially the same functions.

[0053] Hereinafter, working principles and embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0054] Figure 1 is a diagram showing the appearance of an induction heating device according to an embodiment.

[0055] exist Figure 1 , a top view of an induction heating device 1 according to an embodiment is shown. Figure 1 The induction heating device 1 according to the embodiment may include a plate 110 disposed on an upper portion thereof, cooking zones 111, 112, and 113 formed on the plate 110, and user interfaces 120 and 130 serving as input / output devices. For example, the plate 110 may be implemented with ceramics.

[0056] The cooking zones 111 , 112 , and 113 may indicate locations where cooking containers may be placed, and may be indicated by a circle (indicated by reference numeral 111 ) or a straight boundary line (indicated by reference numerals 112 and 113 ) to guide proper arrangement of the cooking containers.

[0057] However, the above shapes are merely examples of the shapes of the cooking zones 111 , 112 , and 113 and are not limited to circular or linear shapes, and various shapes may be applied to the embodiment of the induction heating device 1 as long as the user can be guided to the location of the cooking zone.

[0058] In addition, this example shows that there are three cooking zones on the plate 110, but the embodiment of the induction heating device 1 is not limited thereto. Only one cooking zone may be formed, and four or more cooking zones may be formed.

[0059] In one area of ​​the board 110, a display 120 and an input device 130 may be provided. The display 120 may include a display device such as a liquid crystal display (LCD) or a light emitting diode (LED), and the input device 130 may include at least one of various input devices such as a touch pad, a button, or a shuttle knob. Alternatively, the display 120 and the input device 130 may be implemented as a touch screen.

[0060] In this example, the display 120 and the input device 130 are provided at positions spaced apart from the cooking zones 111, 112, and 113 on the plate 110. However, Figure 1 The arrangement shown in FIG. 1 is merely an example applicable to the induction heating device 1 , and the display 120 or the input device 130 may be placed at a location other than on the plate 110 , such as in front of the heating cooking device 100 .

[0061] Combination Figure 1 refer to Figure 2 and Figure 3 , the heating coil 240 for heating the container 10 placed on the plate 110 may be disposed below the plate 110. For ease of description, Figure 2 and Figure 3 Only one heating coil 240 is shown in the figure, but the number of heating coils 240 may be provided to correspond to the number of cooking zones.

[0062] When Figure 1 When three cooking zones 111 , 112 , and 113 are provided as shown in the example, the heating coil 240 may be provided as three heating coils 240 , and each heating coil 240 may be placed at the lower side of a corresponding one of the cooking zones 111 , 112 , and 113 .

[0063] The heating coil 240 may be connected to a coil driving circuit ( Figure 5 2), and a high-frequency current may be supplied from the coil drive circuit 2. For example, the frequency of the high-frequency current may be in the range of 20 kHz to 35 kHz.

[0064] When the heating coil 240 is supplied with a high-frequency current, magnetic lines of force ML may be formed in or around the heating coil 240. When the container 10 having a resistor is located within the range reached by the magnetic lines of force ML, the magnetic lines of force ML around the heating coil 240 may pass through the bottom of the container 10, thereby generating an induced current in the form of an eddy current, i.e., an eddy current (EC), according to the law of electromagnetic induction.

[0065] The eddy current EC may interact with the electrical resistance of the container 10 to generate heat within or on the container 10 , and the generated heat may heat the food within the container 10 .

[0066] In the induction heating device 1 , the container 10 itself serves as a heat source, and a metal having a certain level or higher of electrical resistance (eg, iron, stainless steel, or nickel) may be used as a material of the container 10 .

[0067] Figure 4 is a block diagram showing a configuration of an induction heating device according to an embodiment.

[0068] refer to Figure 4 The induction heating device 1 according to the embodiment may include a coil driving circuit 2 for supplying a driving current to the heating coil 240 .

[0069] The coil driving circuit 2 may include a power module 20 that supplies power for heating the container 10 to the heating coil 240 , and a circuit configuration that converts the power supplied from the power module 20 into alternating current and supplies the alternating current to the heating coil 240 .

[0070] In one embodiment, the coil driving circuit 2 may include a first switching element SW1 and a second switching element SW2 for supplying the power supplied from the power module 20 to the heating coil 240 .

[0071] The first switching element SW1 and the second switching element SW2 may operate in a complementary manner to allow an alternating current to flow through the heating coil 240 .

[0072] The first switch element SW1 and the second switch element SW2 can be turned on / off by a switch driving signal. In this case, the switch driving signal can be provided by the controller 150, and the controller 150 can alternately turn on / off the first switch element SW1 and the second switch element SW2, thereby supplying high-frequency alternating current to the heating coil 240.

[0073] The first switch element SW1 and the second switch element SW2 can be implemented as a three-terminal semiconductor device switch with a fast response speed, so as to be turned on / off at a high speed. For example, the first switch element SW1 and the second switch element SW2 can be set as a bipolar junction transistor (BJT), a metal oxide semiconductor field effect transistor (MOSFET), an insulated gate bipolar transistor (IGBT) or a thyristor.

[0074] In addition, the coil driving circuit 2 may include a current sensor 230 that detects a current supplied to the heating coil 240 .

[0075] A current sensor 230 may be installed on a current path between a contact point of the first and second switching elements SW1 and SW2 and the heating coil 240. The current sensor 230 may detect the magnitude of a current flowing through the heating coil 240 or the magnitude of a driving current supplied to the heating coil 240.

[0076] The current sensor 230 may include a current transformer configured to proportionally reduce the magnitude of the driving current supplied to the heating coil 240 and an ammeter configured to detect the magnitude of the proportionally reduced current.

[0077] Information about the magnitude of the current detected by the current sensor 230 may be provided to the controller 150. The controller 150 may adjust the magnitude of the high frequency current applied to the heating coil 240 based on the information about the magnitude of the detected current.

[0078] In addition, the controller 150 can identify whether the container 10 is located on the heating coil 240 based on the information about the magnitude of the detected current. For example, in response to the magnitude of the detected current being lower than a reference value, it can be identified that the container 10 is located on the heating coil 240. On the contrary, in response to the magnitude of the detected current being greater than or equal to the reference value, the controller 150 can identify that the container 10 is not located on the heating coil 240.

[0079] When it is recognized that the container 10 is not located on the heating coil 240 while the high-frequency current is being applied to the heating coil 240, the controller 150 may cut off the high-frequency current applied to the heating coil 240, thereby improving the stability of the induction heating device 1.

[0080] Meanwhile, before performing the operation of applying a high-frequency current to the heating coil 240, that is, before entering the heating mode, the controller 150 may identify whether the container 10 is located on the heating coil 240, and when it is identified that the container 10 is not located on the heating coil 240, prevent the high-frequency current from being applied to the heating coil 240. That is, the high-frequency current may be applied to the heating coil 240 only when the container 10 is located on the heating coil 240.

[0081] In addition, the induction heating device 1 according to the embodiment may include a controller 150 configured to control the operation of the induction heating device 1. The controller 150 may include: at least one memory 152 in which a program for performing the operation described below is stored; and at least one processor 151 configured to execute the stored program.

[0082] The at least one processor 151 may include a microprocessor. A microprocessor is a processing device that includes an arithmetic logic operator, a register, a program counter, a command decoder, a control circuit, etc., in at least one silicon chip.

[0083] The microprocessor may include a graphics processing unit (GPU). The microprocessor may be implemented in the form of a system on chip (SoC) including a core and a GPU. The microprocessor may include a single core, a dual core, a triple core, a quad core, and multiple cores.

[0084] Furthermore, the at least one processor 151 may include an input / output processor configured to mediate data access between various components included in the induction heating device 1 and the controller 150 .

[0085] The at least one memory 152 may include a nonvolatile memory such as a read only memory (ROM), a high-speed random access memory (RAM), a disk storage device, or a flash memory device, or other types of nonvolatile semiconductor memory devices.

[0086] For example, at least one memory 152 may be a semiconductor memory device including at least one of a secure digital (SD) memory card, a secure digital high capacity (SDHC) memory card, a mini SD memory card, a mini SDHC memory card, a Trans Flash (TF) memory card, a micro SD memory card, a micro SDHC memory card, a memory stick, a compact flash (CF), a multimedia card (MMC), an MMC micro, or an extreme digital (XD) card.

[0087] Additionally, the at least one memory 152 may include a network attached storage device allowing access over a network.

[0088] The controller 150 may control the induction heating device 1 based on user input received through the input device 130. For example, the input device 130 may receive user input related to power on / off, selection of one or more of the cooking zones 111, 112, and 113, selection of the heating intensity of the selected cooking zone, setting of a timer, etc.

[0089] For example, the controller 150 may select to supply high frequency power to the heating coil 240 according to the selection of the cooking zone received through the input device 130, and may adjust the strength of the magnetic field generated by the heating coil 240 according to the selection of the heating intensity received through the input device 130. In a configuration with a single cooking zone, the heating intensity may be directly selected without selecting a cooking zone.

[0090] When the input device 130 receives a selection of the heating intensity from the user, the controller 150 may determine the on / off frequency of the first switching element SW1 and the second switching element SW2 based on the selected heating intensity. The controller 150 may alternately turn on / off the first switching element SW1 and the second switching element SW2 according to the determined on / off frequency, thereby applying a high-frequency current having a frequency corresponding to the selected heating intensity to the heating coil 240.

[0091] When the input device 130 receives a selection to start heating from the user, the controller 150 may control the power module 20 so that power of the power module 20 is supplied to the coil driving circuit 2 .

[0092] The display 120 may display information about the current state of the induction heating device 1, information for guiding the selection of one or more cooking zones and / or heating intensity, and information for guiding timer setting. In addition, the display 120 may display a notification indicating whether the container 10 exists.

[0093] Figure 5 is a diagram showing an example of a coil driving circuit according to an embodiment.

[0094] refer to Figure 5According to the embodiment, the coil driving circuit 2 may include a power supply module 20, an inverter circuit including a first switching element SW1 and a second switching element SW2, at least one inductor L1, at least one diode D1, D2, RD1 and RD2, at least one capacitor C1, C2 and C3, and at least one node N1, N2 and N3 for defining a positional relationship of at least one electrical element.

[0095] The power module 20 may include a power source 201 that supplies or blocks AC power to the circuit configuration and a filter 210 that removes noise components included in power supplied from the power source 201 .

[0096] The controller 150 may turn on or off the power source 201 based on a user input received through the input device 130 .

[0097] According to various embodiments, the controller 150 may turn off the power supply 201 based on satisfaction of a preset condition regardless of the user input.

[0098] For example, the controller 150 may turn on the power supply 201 based on receiving a heating start command, and may turn off the power supply 201 based on not detecting a container on the heating coil 240 within a preset time.

[0099] The filter 210 may be composed of a converter and a capacitor, and may remove noise mixed in the power supplied from the power source 201 .

[0100] In the present disclosure, the power module 20 may be defined as a configuration that does not include a rectifier for converting an AC voltage into a DC voltage.

[0101] The power module 20 may have a first terminal T1 and a second terminal T2 .

[0102] A potential difference may be formed between the first terminal T1 and the second terminal T2 according to the AC voltage supplied from the power module 20. That is, AC power may be supplied to the first terminal T1 and the second terminal T2.

[0103] The first terminal T1 and the second terminal T2 may be directly connected to the power source 201 , or may be directly connected to the filter 210 .

[0104] The potential difference V1 formed between the first terminal T1 and the second terminal T2 can be defined as an input voltage, and the input voltage V1 having a positive (+) value means that the potential of the first terminal T1 can be higher than the potential of the second terminal T2, and the input voltage V1 having a negative (-) value means that the potential of the second terminal T2 can be higher than the potential of the first terminal T1.

[0105] That is, supplying a positive voltage to the first terminal T1 means that the potential of the first terminal T1 is higher than that of the second terminal T2 , and supplying a negative voltage to the first terminal T1 means that the potential of the second terminal T2 is higher than that of the first terminal T1 .

[0106] The coil driving circuit 2 may include a first node N1 , a second node N2 , and a third node N3 .

[0107] The first node N1 may refer to a contact point between the first switching element SW1 and the second switching element SW2 .

[0108] For example, the first node N1 may refer to a node between a source terminal (or emitter terminal) of the first switching element SW1 and a drain terminal (or collector terminal) of the second switching element SW2 .

[0109] The inductor L1 may be connected between the first terminal T1 and the first node N1 .

[0110] The second node N2 may refer to a node of a drain terminal (or a collector terminal) of the first switching element SW1 .

[0111] In addition, the second node N2 may refer to a node on the cathode side of the first diode D1.

[0112] The first switching element SW1 may be connected between the first node N1 and the second node N2 .

[0113] The first anti-parallel diode RD1 may be connected in parallel with the first switching element SW1 .

[0114] The first anti-parallel diode RD1 may have a cathode connected to the second node N2 and an anode connected to the first node N1.

[0115] The second switching element SW2 may be connected between the first node N1 and the ground node GND.

[0116] The ground node GND may refer to a node on the ground side.

[0117] The second anti-parallel diode RD2 may be connected in parallel with the second switching element SW2 .

[0118] The second anti-parallel diode RD2 may have a cathode connected to the first node N1 and an anode connected to the ground node GND.

[0119] An anode of the first diode D1 may be connected to a cathode of the second diode D2 , and an anode of the first diode D1 and a cathode of the second diode D2 may be connected to the second terminal T2 .

[0120] The first diode D1 may be connected to the second node N2 and the second terminal T2 .

[0121] That is, the first diode D1 may have a cathode connected to the second node N2 and an anode connected to the second terminal T2.

[0122] The second diode D2 may be connected to the second terminal T2 and the ground node GND.

[0123] That is, a cathode of the second diode D2 may be connected to the second terminal T2 , and an anode of the second diode D2 may be connected to the ground node GND.

[0124] The third node N3 may refer to a node between the first capacitor C1 and the second capacitor C2 .

[0125] The heating coil 240 may be disposed between the first node N1 and the third node N3 .

[0126] The first capacitor C1 may be connected to the second node N2 and the third node N3 .

[0127] The second capacitor C2 may be connected to the third node N3 and the ground node GND.

[0128] The third capacitor C3 may be connected to the second node N2 and the ground node GND.

[0129] Therefore, the first capacitor C1 and the second capacitor C2 may form a parallel relationship with the third capacitor C3.

[0130] The circuit configuration included in the conventional induction heating device allows a DC voltage converted by a rectifier to pass through an inverter circuit and then be supplied to a heating coil.

[0131] On the other hand, the coil driving circuit 2 according to the embodiment has a structure similar to a totem pole topology. In addition, the coil driving circuit 2 may include a third capacitor C3 connected in parallel with the first capacitor C1 and the second capacitor C2.

[0132] According to the present disclosure, when a container having low magnetic permeability is used, the output can be increased. In addition, according to the present disclosure, the noise generated when a high-frequency current is applied to the heating coil 240 can be reduced.

[0133] Between the first node N1 and the third node N3 , a current sensor 230 may be provided to measure a current applied to the heating coil 240 .

[0134] In addition, a resistor R1 may be disposed between the first node N1 and the third node N3 .

[0135] The resistor R1 may have an appropriate resistance value according to the capacitances of the capacitors C1 , C2 , and C3 .

[0136] Hereinafter, current flow according to the switching operation of the switching elements SW1 and SW2 will be described.

[0137] Figure 6 is a graph showing a change in current over time according to operations of a first switching element and a second switching element when a positive voltage is applied to a first terminal. Figure 7 is a graph showing a change in current over time according to operations of a first switching element and a second switching element when a negative voltage is applied to a first terminal.

[0138] refer to Figure 6 and Figure 7 , in the heating mode, the controller 150 may operate the first switching element SW1 and the second switching element SW2 in a complementary manner.

[0139] Furthermore, the controller 150 may turn off both the first switching element SW1 and the second switching element SW2 .

[0140] In one embodiment, the controller 150 can perform a first operation of disconnecting the first switch element SW1 and turning on the second switch element SW2 for a preset time, and can perform a second operation of disconnecting both the first switch element SW1 and the second switch element SW2 for a preset time, and can perform a third operation of turning on the first switch element SW1 and disconnecting the second switch element SW2 for a preset time.

[0141] The controller 150 may perform the first operation by outputting a switching signal for turning off the first switching element SW1 and outputting a switching signal for turning on the second switching element SW2 .

[0142] In addition, the controller 150 may perform the second operation by outputting a switching signal for turning off the first switching element SW1 and outputting a switching signal for turning off the second switching element SW2 .

[0143] In addition, the controller 150 may perform the third operation by outputting a switching signal for turning on the first switching element SW1 and outputting a switching signal for turning off the second switching element SW2 .

[0144] In one embodiment, the controller 150 may repeatedly perform the first operation, the second operation, the third operation, and the second operation.

[0145] In this case, the execution cycle of the first operation may be the same as the execution cycle of the third operation.

[0146] Furthermore, an execution period of the first operation and / or an execution period of the third operation may be longer than an execution period of the second operation.

[0147] refer to Figure 6, when a positive voltage is applied to the first terminal T1, the current flow of the coil driving circuit 2 can be divided into a plurality of modes according to the switching operation of the switching elements SW1 and SW2.

[0148] The input current may refer to a current flowing from the first terminal T1 to the second terminal T2 .

[0149] The sign of the input current can indicate the direction of the current.

[0150] When the input current has a positive value, the input current may have a direction flowing from the first terminal T1 to the second terminal T2 (hereinafter referred to as "forward direction"). Conversely, when the input current has a negative value, the input current may have a direction flowing from the second terminal T2 to the first terminal T1 (hereinafter referred to as "reverse direction").

[0151] The resonance current may refer to a current flowing from the first node N1 to the third node N3 .

[0152] The sign of the resonant current can indicate the direction of the current.

[0153] When the resonant current has a positive value, the resonant current may have a direction flowing from the first node N1 to the third node N3 (hereinafter referred to as a "forward direction"). Conversely, when the resonant current has a negative value, the resonant current may have a direction flowing from the third node N3 to the first node N1 (hereinafter referred to as a "reverse direction").

[0154] The first current may refer to a current flowing through the first switching element SW1 or the first anti-parallel diode RD1 , and may refer to a current flowing from the second node N2 to the first node N1 .

[0155] The sign of the first current may indicate the direction of the current.

[0156] When the first current has a positive value, the current may have a direction (hereinafter referred to as "forward") to sequentially flow through the second node N2 and the first switching element SW1 to reach the first node N1. Conversely, when the first current has a negative value, the current may have a direction (hereinafter referred to as "reverse") to sequentially flow through the first node N1 and the first reverse-parallel diode RD1 to reach the second node N2.

[0157] The second current may refer to a current flowing through the second switching element SW2 or the second anti-parallel diode RD2 , and may refer to a current flowing from the first node N1 to the ground node GND.

[0158] The sign of the second current may indicate the direction of the current.

[0159] When the second current has a positive value, the current may have a direction (hereinafter referred to as "forward") that sequentially flows through the first node N1 and the second switch element SW2 to reach the ground node GND. Conversely, when the second current has a negative value, the current may have a direction (hereinafter referred to as "reverse") that sequentially flows through the ground node GND and the second anti-parallel diode RD2 to reach the first node N1.

[0160] When a positive voltage is applied to the first terminal T1 and the controller 150 repeatedly performs the first operation, the second operation, the third operation, and the second operation, a current flow in the coil driving circuit 2 may be divided into five areas.

[0161] Five aspects in which current flows when a positive voltage is applied to the first terminal T1 may be defined as first to fifth modes.

[0162] [First Mode]

[0163] It can be seen that in response to the controller 150 performing the first operation, the input current in the forward direction gradually increases, the resonant current in the reverse direction gradually increases, and the second current in the forward direction gradually increases.

[0164] [Second Mode]

[0165] It can be seen that in response to the controller 150 performing the second operation after completing the first operation, the flow of the second current stops, the forward input current gradually decreases, the reverse resonant current gradually decreases, and the reverse first current gradually decreases.

[0166] Furthermore, the second mode may be maintained during a portion of a period in which the controller 150 performs the third operation after completing the second operation.

[0167] [Third Mode]

[0168] In response to the controller 150 performing the third operation within a predetermined time after completing the second operation, the direction of the resonant current and the direction of the first current may be switched.

[0169] During a portion of a period in which the controller 150 is performing the third operation, the input current in the forward direction may gradually decrease, the resonant current in the forward direction may gradually increase, and the first current in the forward direction may gradually increase.

[0170] [Fourth Mode]

[0171] When a predetermined time elapses after the controller 150 starts the third operation, the flow of the input current may be stopped.

[0172] During a portion of the period in which the controller 150 is performing the third operation, the input current may not flow, the forward resonant current may gradually increase, and the forward first current may gradually increase.

[0173] [Fifth Mode]

[0174] In response to the controller 150 performing the second operation after completing the third operation, the flow of the first current may be stopped, and the reverse second current may flow.

[0175] In response to the controller 150 performing the second operation after completing the third operation, the forward input current may gradually increase, the forward resonant current may gradually decrease, and the reverse second current may gradually decrease.

[0176] refer to Figure 7 , when a negative voltage is applied to the first terminal T1, the current flow in the coil driving circuit 2 may be divided into a plurality of modes according to the switching operations of the switching elements SW1 and SW2.

[0177] When a negative voltage is applied to the first terminal T1 and the controller 150 repeatedly performs the first operation, the second operation, the third operation, and the second operation, a current flow in the coil driving circuit 2 may be divided into five areas.

[0178] Five aspects in which current flows when a negative voltage is applied to the first terminal T1 may be defined as sixth to tenth modes.

[0179] [Sixth Mode]

[0180] In response to the controller 150 starting the first operation, the reverse input current may gradually decrease, the direction of the resonant current may be switched from the forward direction to the reverse direction, and the direction of the second current may be switched from the reverse direction to the forward direction.

[0181] [Seventh Mode]

[0182] When a predetermined time elapses after the controller 150 starts the first operation, the flow of the input current may be stopped.

[0183] During a portion of the period in which the controller 150 is performing the first operation, the input current may not flow, the reverse resonance current may gradually increase, and the forward second current may gradually increase.

[0184] [Eighth Mode]

[0185] In response to the controller 150 performing the second operation after completing the first operation, the input current may start to flow, the flow of the second current may stop, and the reverse first current may flow.

[0186] In response to the controller 150 performing the second operation after completing the first operation, the reverse input current may gradually increase, the reverse resonance current may gradually decrease, and the reverse first current may gradually decrease.

[0187] [Ninth Mode]

[0188] In response to the controller 150 starting the third operation after completing the second operation, the direction of the resonant current and the direction of the first current may be switched.

[0189] When the controller 150 is performing the third operation, the reverse input current may gradually increase, the forward resonant current may gradually increase, and the forward first current may gradually increase.

[0190] [Tenth Mode]

[0191] In response to the controller 150 performing the second operation after completing the third operation, the flow of the first current stops, and the reverse second current may flow.

[0192] In response to the controller 150 performing the second operation after completing the third operation, the reverse input current may gradually decrease, the forward resonant current may gradually decrease, and the reverse second current may gradually decrease.

[0193] refer to Figure 6 and Figure 7 , the third capacitor C3 provides the effect of smoothing the resonant current.

[0194] Therefore, noise generated when a high-frequency current is applied to the heating coil 240 can be reduced.

[0195] In the following, reference will be made to Figures 8 to 19 The flow of current in the coil drive circuit 2 according to the switching operation is described in more detail.

[0196] Figure 8 is a diagram schematically showing the flow of current when a positive voltage is applied to the first terminal in a state where the first switching element and the second switching element are in an off state.

[0197] The controller 150 may control the power module to supply power to the coil driving circuit 2 based on the start of the heating operation.

[0198] In one embodiment, the controller 150 may start the heating operation based on receiving a user input for starting heating.

[0199] In one embodiment, the controller 150 may not perform the switching operation for a predetermined time after the heating operation starts. That is, the controller 150 may maintain the first switching element SW1 and the second switching element SW2 in an off state for a predetermined time after the heating operation starts.

[0200] refer to Figure 8In response to applying a positive voltage to the first terminal T1 while the first switching element SW1 and the second switching element SW2 remain in a disconnected state, an input current may sequentially flow through the first terminal T1, the inductor L1, the first anti-parallel diode RD1, the third capacitor C3 and the second diode D2 to reach the second terminal T2.

[0201] Therefore, in response to a positive voltage being applied to the first terminal T1 while the first switching element SW1 and the second switching element SW2 are maintained in a turned-off state, the third capacitor C3 may be charged.

[0202] Fig. 9 is a diagram schematically showing a flow of current when a negative voltage is applied to the first terminal T1 in a state where the first switching element and the second switching element are in an off state.

[0203] refer to Fig. 9 In response to applying a negative voltage to the first terminal T1 while the first switching element SW1 and the second switching element SW2 remain in a disconnected state, an input current may sequentially flow through the second terminal T2, the first diode D1, the third capacitor C3, the second anti-parallel diode RD2 and the inductor L1 to reach the first terminal T1.

[0204] Therefore, in response to a negative voltage being applied to the first terminal T1 while the first and second switching elements SW1 and SW2 are maintained in a turned-off state, the third capacitor C3 may be charged.

[0205] According to the present disclosure, after the heating operation starts and before the switching operation starts, in response to the power being supplied from the power module 20 , the third capacitor C3 may be charged.

[0206] As described above, the controller 150 can perform the first operation, the second operation, and the third operation based on the start of the heating operation. In one embodiment, the controller 150 can keep the first and second switching elements SW1 and SW2 in the off state for a predetermined time after the start of the heating operation, and then start the switching operation based on the elapse of the predetermined time.

[0207] Fig.10 It is schematically shown Figure 6 Diagram of the current flow in the first mode.

[0208] refer to Fig.10 When a positive voltage is applied to the first terminal T1 and the first operation is performed, the input current can sequentially flow through the first terminal T1, the inductor L1, the second switching element SW2 and the second diode D2 to reach the second terminal T2, and the resonant current can sequentially flow through the third node N3, the heating coil and the second switching element SW2 to reach the ground node GND.

[0209] In the first mode, since the charging of the third capacitor C3 is completed before the switching operation starts, the condition that the voltage charged in the third capacitor C3 is greater than the voltage at the first node N1 is satisfied. Since the voltage charged in the third capacitor C3 is greater than the voltage at the first node N1, the first reverse parallel diode RD1 is not turned on, and a current path flowing to the second switching element SW2 is formed. Accordingly, the input current sequentially flows through the first terminal T1, the inductor L1, the second switching element SW2, and the second diode D2 to reach the second terminal T2.

[0210] In the first mode, the resonance current charged in the first capacitor C1 and the heating coil flows through the second switching element SW2 until the resonance current is discharged according to the current inertia of the inductor L1.

[0211] That is, in the first mode, the resonant current may sequentially flow through the third node N3, the heating coil, and the second switching element SW2 to reach the ground node GND.

[0212] Therefore, a resonant current in the opposite direction flows through the heating coil.

[0213] In summary, since both the input current and the resonance current flow through the second switching element SW2 , the second switching element SW2 needs to have a current capacity sufficient to allow both the input current and the resonance current to flow simultaneously.

[0214] The controller 150 may perform the first operation for a preset time and then perform the second operation. In this case, the execution period of the first operation may be longer than the execution period of the second operation.

[0215] Fig.11 It is schematically shown Figure 6 FIG. 1 is a diagram of the current flow in the second mode.

[0216] refer to Fig.11 When a positive voltage is applied to the first terminal T1 and the second operation is performed, the input current can sequentially flow through the first terminal T1, the inductor L1, the first reverse-parallel diode RD1, the third capacitor C3 and the second diode D2 to reach the second terminal T2, and the resonant current can sequentially flow through the third node N3, the heating coil and the first reverse-parallel diode RD1 to reach the second node N2.

[0217] The second mode may be maintained during a period in which the controller 150 performs the second operation after completing the first operation and during a portion of a period in which the controller 150 performs the third operation after completing the second operation.

[0218] That is, the second mode may be divided into a period in which the second operation is performed and a portion of a period in which the third operation is performed after the second operation is completed.

[0219] In response to the controller 150 performing the second operation after performing the first operation, the second switching element SW2 in the on state changes to the off state.

[0220] As a result of performing the first operation for the preset period of time, a condition that the magnitude of the voltage charged in the third capacitor C3 is smaller than the magnitude of the voltage of the first node N1 is satisfied.

[0221] Since the voltage charged in the third capacitor C3 is smaller than the voltage at the first node N1, a current path to the first anti-parallel diode RD1 is formed. Therefore, the input current and the resonance current flow through the first anti-parallel diode RD1.

[0222] As described above, since both the input current and the resonance current flow through the first anti-parallel diode RD1 , the first anti-parallel diode RD1 needs to have a current capacity sufficient to allow both the input current and the resonance current to flow simultaneously.

[0223] According to various embodiments, the first switching element SW1 and the first anti-parallel diode RD1 need to be implemented as components having the same current capacity.

[0224] Since a negative voltage is applied to the second terminal T2 when a positive voltage is applied to the first terminal T1, the second diode D2 may be turned on and the second reverse parallel diode RD2 may not be turned on. Therefore, a current path flowing through the second diode D2 is formed, and the current flowing through the third capacitor C3 flows through the second diode D2 to reach the second terminal T2.

[0225] That is, in the second mode, the input current may sequentially flow through the first terminal T1 , the inductor L1 , the first anti-parallel diode RD1 , the third capacitor C3 , and the second diode D2 to reach the second terminal T2 .

[0226] In one embodiment, when the first switch element SW1 and the second switch element SW2 are in an off state, a boost power factor correction (PFC) circuit is formed by the structure of the inductor L1 , the second switch element SW2 , the first anti-parallel diode RD1 and the third capacitor C3 .

[0227] Therefore, in a state where the second switch element SW2 is turned off, the current charged in the inductor L1 is continuously discharged, the current discharged from the inductor L1 is charged in the third capacitor C3, and the charging voltage of the third capacitor C3 increases.

[0228] That is, in the second mode, the resonant current may sequentially flow through the third node N3, the heating coil, and the first anti-parallel diode RD1 to reach the second node N2.

[0229] The value of the current flowing through the third capacitor C3 corresponds to the sum of half the resonance current value and the input current value.

[0230] When the controller 150 starts the third operation after completing the second operation, a zero voltage switching (ZVS) operation is established.

[0231] On the other hand, when the current charged in the inductor L1 is discharged to a certain extent, the amount of charge in the inductor L1 and the amount of charge in the first capacitor C1 are balanced, so that the amplitude of the resonance current becomes zero.

[0232] Fig.12 It is schematically shown Figure 6 FIG. 5 is a diagram of the current flow in the third mode.

[0233] refer to Fig.12 When a positive voltage is applied to the first terminal T1 and the third operation is performed, the input current can sequentially flow through the first terminal T1, the inductor L1, the heating coil, the second capacitor C2 and the second diode D2 to reach the second terminal T2, and the resonant current can sequentially flow through the second node N2, the first switching element SW1 and the heating coil to reach the third node N3.

[0234] When a predetermined time elapses after the controller 150 starts the third operation, the magnitude of the resonance current may become 0, and the direction of the resonance current may change.

[0235] Therefore, when a predetermined time elapses after the controller 150 starts the third operation, the first capacitor C1 starts to discharge, and the direction of the resonance current changes from the reverse direction to the forward direction.

[0236] That is, in the third mode, the resonant current sequentially flows through the second node N2, the first switching element SW1, and the heating coil to reach the third node N3.

[0237] As the direction of the resonant current changes, the first anti-parallel diode RD1 does not conduct.

[0238] Therefore, the input current flows to the heating coil together with the resonant current.

[0239] In addition, since the voltage of the first node N1 is higher than the voltage of the ground node GND, the second anti-parallel diode RD2 is not turned on. On the other hand, since the voltage of the second terminal T2 is lower than the voltage of the ground node GND, the second diode D2 is turned on.

[0240] That is, in the third mode, the input current may sequentially flow through the first terminal T1 , the inductor L1 , the heating coil, the second capacitor C2 , and the second diode D2 to reach the second terminal T2 .

[0241] Fig.13 It is schematically shown Figure 6 FIG. 4 is a diagram of the current flow in the fourth mode.

[0242] refer to Fig.13 , when a positive voltage is applied to the first terminal T1 and the third operation is performed, in a state where the input current does not flow, the resonant current may sequentially flow through the second node N2, the first switching element SW1, and the heating coil to reach the third node N3.

[0243] When a predetermined time elapses after the controller 150 starts the third operation, the current charged in the inductor L1 is completely discharged.

[0244] When the current charged in the inductor L1 is completely discharged, the input current no longer flows, the first capacitor C1 is discharged, and the resonant current flows.

[0245] Therefore, in a state where the input current does not flow, the resonance current may sequentially flow through the second node N2 , the first switching element SW1 , and the heating coil to reach the third node N3 .

[0246] In the fourth mode, the magnitude of the current flowing through the third capacitor C3 is equal to the magnitude of the current flowing through the first capacitor C1.

[0247] Fig.14 It is schematically shown Figure 6 FIG. 5 is a diagram of the current flow in the fifth mode.

[0248] refer to Fig.14 When a positive voltage is applied to the first terminal T1 and the second operation is performed, the input current can sequentially flow through the first terminal T1, the inductor L1, the heating coil, the first capacitor C1, the third capacitor C3 and the second diode D2 to reach the second terminal T2, and the resonant current can sequentially flow through the ground node GND, the second switching element SW2 and the heating coil to reach the third node N3.

[0249] When the controller 150 starts the second operation after completing the third operation, the current charged in the heating coil is discharged into the first capacitor C1 and the second capacitor C2.

[0250] Therefore, the magnitude of the voltage of the first node N1 becomes smaller than zero, and thus the input current starts to flow again.

[0251] In this case, since the voltage charged in the third capacitor C3 is greater than the voltage at the first node N1, the first reverse-parallel diode RD1 is not conductive, and thus, the input current can flow sequentially through the first terminal T1, the inductor L1, the heating coil, the first capacitor C1, the third capacitor C3 and the second diode D2 to reach the second terminal T2.

[0252] At the same time, the amplitude of the voltage of the first node N1 becomes less than 0, so that the second anti-parallel diode RD2 is turned on, and thus the resonance current can sequentially flow through the ground node GND, the second switching element SW2 and the heating coil to reach the third node N3.

[0253] Fig.15 It is schematically shown Figure 7 FIG. 1 is a diagram of the current flow in the sixth mode.

[0254] refer to Fig.15 When a negative voltage is applied to the first terminal T1 and the first operation is performed, the input current can sequentially flow through the second terminal T2, the first diode D1, the first capacitor C1, the heating coil and the inductor L1 to reach the first terminal T1, and the resonant current can sequentially flow through the third node N3, the heating coil and the second switching element SW2 to reach the ground node GND.

[0255] When a negative voltage is applied to the first terminal T1, a positive voltage is applied to the second terminal T2. When the condition that the voltage applied to the second terminal T2 is greater than the voltage charged in the third capacitor C3 is satisfied, the first diode D1 is turned on. In addition, the second diode D2 and the second reverse parallel diode RD2 are not turned on according to the voltage condition.

[0256] Therefore, the input current sequentially flows through the second terminal T2 , the first diode D1 , the first capacitor C1 , the heating coil, and the inductor L1 to reach the first terminal T1 .

[0257] Meanwhile, since the first switching element SW1 is in an off state, the resonance current flows to the ground node GND through the heating coil and the second switching element SW2.

[0258] Fig.16 It is schematically shown Figure 7 Diagram of the current flow in the seventh mode.

[0259] refer to Fig.16 , when a negative voltage is applied to the first terminal T1 and the first operation is performed, in a state where the input current does not flow, the resonant current may sequentially flow through the third node N3 , the heating coil, and the second switching element SW2 to reach the ground node GND.

[0260] When a predetermined time elapses after the controller 150 starts the first operation, the current charged in the inductor L1 is completely discharged.

[0261] When the current charged in the inductor L1 is completely discharged, the input current no longer flows, the second capacitor C2 is discharged, and the resonant current flows.

[0262] Fig.17 It is schematically shown Figure 7 Diagram of the current flow in the eighth mode.

[0263] refer to Fig.17 When a negative voltage is applied to the first terminal T1 and the second operation is performed, the input current can sequentially flow through the second terminal T2, the first diode D1, the first capacitor C1, the heating coil and the inductor L1 to reach the first terminal T1, and the resonant current can sequentially flow from the third node N3, the heating coil and the switching element to the second node N2.

[0264] When the controller 150 performs the second operation after completing the first operation, the second switching element SW2 in the on state is switched to the off state.

[0265] As the second switch element SW2 is switched to the off state, the first anti-parallel diode RD1 is turned on and causes the resonant current directed to the ground node GND through the second switch element SW2 in the seventh mode to flow to the second node N2 through the first anti-parallel diode RD1 .

[0266] Furthermore, as the second switching element SW2 is switched to an off state, the first diode D1 is turned on, and the input current sequentially flows through the second terminal T2 , the first diode D1 , the first capacitor C1 , the heating coil, and the inductor L1 to reach the second terminal T2 .

[0267] Fig.18 It is schematically shown Figure 7 Diagram of the current flow in the ninth mode.

[0268] refer to Fig.18 When a negative voltage is applied to the first terminal T1 and the third operation is performed, the input current can sequentially flow through the second terminal T2, the first diode D1, the first switching element SW1 and the inductor L1 to reach the first terminal T1, and the resonant current can sequentially flow through the second node N2, the first switching element SW1 and the heating coil to reach the third node N3.

[0269] When the controller 150 performs the third operation after completing the second operation, the first switching element SW1 in the off state is switched to the on state.

[0270] Therefore, the resonance current and the input current may flow through the first switching element SW1.

[0271] Fig.19 It is schematically shown Figure 7 Diagram of the current flow in the tenth mode.

[0272] refer to Fig.19When a negative voltage is applied to the first terminal T1 and the second operation is performed, the input current can sequentially flow through the second terminal T2, the first diode D1, the third capacitor C3, the second reverse-parallel diode RD2 and the inductor L1 to reach the first terminal T1, and the resonant current can sequentially flow through the ground node GND, the second reverse-parallel diode RD2 and the heating coil to reach the third node N3.

[0273] When the controller 150 performs the second operation after completing the third operation, the first switching element SW1 in the on state is switched to the off state.

[0274] As the first switch element SW1 is switched to the off state, the second anti-parallel diode RD2 is turned on and causes the resonant current directed from the second node N2 to the first node N1 through the first switch element SW1 in the ninth mode to flow from the ground node GND to the first node N1 through the second anti-parallel diode RD2.

[0275] In addition, as the first switch element SW1 is switched to an off state, the input current may not flow to the first switch element SW1, but may sequentially flow through the second terminal T2, the first diode D1, the third capacitor C3, the second anti-parallel diode RD2 and the inductor L1 to reach the first terminal T1.

[0276] According to the present disclosure, since the amplitude of the resonant current passing through the heating coil is maintained at a constant value, noise generated when the container is heated can be reduced.

[0277] Furthermore, according to the present disclosure, since the amplitude of the resonant current passing through the heating coil is maintained at a constant value, a container having a low magnetic permeability can be efficiently heated.

[0278] Furthermore, according to the present disclosure, since the voltage is boosted by the third capacitor, the output can be improved even when a switching element having a fixed current capacity is used.

[0279] Meanwhile, the disclosed embodiments may be implemented in the form of a recording medium storing computer executable instructions. The instructions may be stored in the form of program codes, and when executed by a processor, a program module may be generated to perform the operations of the disclosed embodiments. The recording medium may be implemented as a computer readable recording medium.

[0280] The computer-readable recording medium includes all types of recording media in which instructions that can be decoded by a computer are stored, such as read-only memory (ROM), random access memory (RAM), magnetic tapes, magnetic disks, flash memories, optical data storage devices, and the like.

[0281] In addition, the computer-readable recording medium may be provided in the form of a non-temporary storage medium. Here, when the storage medium is referred to as "non-temporary", it can be understood that the storage medium is tangible and does not include a signal (electromagnetic wave), but data is semi-permanently or temporarily stored in the storage medium. For example, the "non-temporary storage medium" may include a buffer that temporarily stores data.

[0282] According to one embodiment, the method according to various embodiments disclosed herein may be provided in the form of a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a machine-readable storage medium (e.g., a compact disk read-only memory (CD-ROM)), or may be distributed through an online application store (e.g., Play StoreTM). In the case of online distribution, at least a portion of the computer program product may be stored at least semi-permanently in a storage medium (e.g., a memory of a manufacturer's server, an application store's server, or a relay server) or may be temporarily generated therein.

[0283] Although the embodiments of the present disclosure have been described with reference to the accompanying drawings, those skilled in the art will appreciate that these inventive concepts may be implemented in different forms without departing from the scope and spirit of the present disclosure and should not be construed as limited to the embodiments set forth herein.

Claims

1. An induction heating device, include: A first node, a second node, and a third node; A power module having a first terminal and a second terminal; an inductor connected between the first terminal and the first node; A first switching element connected between the first node and the second node; a first anti-parallel diode connected to the first switching element; A second switch element connected between the first node and a ground node; a second anti-parallel diode connected to the second switching element; a first diode having a first cathode connected to the second node and a first anode connected to the second terminal; a second diode having a second cathode connected to the second terminal and a second anode connected to the ground node; a first capacitor connected to the second node and the third node; a second capacitor connected to the third node and the ground node; a third capacitor connected to the second node and the ground node; as well as A heating coil is connected between the first node and the third node.

2. The induction heating device according to claim 1, further comprising: include: A current sensor is connected between the first node and the third node.

3. The induction heating device according to claim 1, further comprising: include: A resistor is connected between the first node and the third node.

4. The induction heating device according to claim 1, in, The power module includes an alternating current (AC) power source and a filter configured to remove noise components included in the AC power source. 5 . The induction heating device of claim 1 , further comprising a controller configured to control the first switching element and the second switching element.

6. The induction heating device according to claim 5, in, The controller is configured to perform: A first operation is to turn off the first switch element and turn on the second switch element; A second operation is to disconnect the first switch element and the second switch element; as well as The third operation turns on the first switch element and turns off the second switch element.

7. The induction heating device according to claim 6, in, The controller is configured to repeatedly perform a sequence of the second operation, the first operation, the third operation, and the second operation.

8. The induction heating device according to claim 6, in, The first period of the first operation and the third period of the third operation are both longer than the second period of the second operation.

9. The induction heating device according to claim 6, in, The controller is configured to: upon start of the heating operation, maintaining the first switching element and the second switching element in an off state for a predetermined time, and In response to a positive voltage being applied to the first terminal while the first switching element and the second switching element remain in an off state, an input current sequentially flows through the first terminal, the inductor, the first anti-parallel diode, the third capacitor, and the second diode to reach the second terminal.

10. The induction heating device according to claim 6, in, The controller is configured to: upon start of the heating operation, maintaining the first switching element and the second switching element in an off state for a predetermined time, and In response to a negative voltage being applied to the first terminal while the first switching element and the second switching element remain in an off state, an input current sequentially flows through the second terminal, the first diode, the third capacitor, the second anti-parallel diode, and the inductor to reach the first terminal.

11. The induction heating device according to claim 6, in, While a positive voltage is applied to the first terminal and the first operation is performed, an input current sequentially flows through the first terminal, the inductor, the second switching element, and the second diode to reach the second terminal, and The resonant current sequentially flows through the third node, the heating coil, and the second switching element to reach the ground node.

12. The induction heating device according to claim 6, in, While applying a positive voltage to the first terminal and performing the second operation, an input current sequentially flows through the first terminal, the inductor, the first anti-parallel diode, the third capacitor, and the second diode to reach the second terminal, and The resonant current sequentially flows through the third node, the heating coil, and the first anti-parallel diode to reach the second node.

13. The induction heating device according to claim 6, in, While a positive voltage is applied to the first terminal and the third operation is performed, an input current sequentially flows through the first terminal, the inductor, the heating coil, the second capacitor, and the second diode to reach the second terminal, and The resonant current sequentially flows through the second node, the first switching element, and the heating coil, and reaches the third node.

14. The induction heating device according to claim 6, in, While a positive voltage is applied to the first terminal and the third operation is performed, a resonant current sequentially flows through the second node, the first switching element, and the heating coil to reach the third node in a state where an input current does not flow.

15. The induction heating device according to claim 6, in, While applying a positive voltage to the first terminal and performing the second operation, an input current sequentially flows through the first terminal, the inductor, the heating coil, the first capacitor, the third capacitor, and the second diode to reach the second terminal, and The resonant current sequentially flows through the ground node, the second switching element, and the heating coil to reach the third node.

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