KR101729020B1 - Cooking apparatus using induction heeating - Google Patents

Abstract

The present invention relates to an induction heating cooker. An induction heating cooking apparatus according to an embodiment of the present invention includes an inverter that includes inverter switching elements and converts an AC power into an AC power by an operation of a switching element and an inverter that is heated by an AC power supply, And a first switching element and a second switching element for switching the first induction heating coil and the second induction heating coil so that the first induction heating coil and the second induction heating coil are respectively connected to the inverter, And the gate signal of the inverter switching element is disabled when at least one of the first and second switching elements is turned on or off. As a result, the switching element for operating the induction heating coil is switched to zero voltage so that it can be efficiently driven.

Description

[0001] The present invention relates to a cooking apparatus using induction heating,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an induction heating cooking appliance, and more particularly, to an induction heating cooking appliance which can be efficiently driven.

Microwave ovens using microwaves, microwave ovens using a heater, cooktop, and the like have been widely used as cooking devices.

The microwave oven is configured to heat the food by heating the microwave generated by the magnetron in the closed cooking chamber to vibrate the water molecule of the food stored in the cooking chamber and heat the sealed cooking chamber using the heater, Heat it.

On the other hand, a cooktop generally cooks a food placed in the vessel by heating the vessel placed on the upper surface thereof, and a gas cooktop having a gas as a heat source is representative. In the case of a gas cooktop, the thermal efficiency due to the flame is large, and thus the efficiency of the cooktop using electricity is increasing.

It is an object of the present invention to provide an induction heating cooking appliance which efficiently drives a switching element for operating an induction heating coil.

It is another object of the present invention to provide an induction heating cooking appliance capable of efficiently driving without power reduction.

Another object of the present invention is to provide an induction heating cooking apparatus capable of stably performing a heating operation without thermal efficiency loss.

According to an aspect of the present invention, there is provided an induction heating cooking apparatus comprising inverter switching elements, an inverter for converting a DC power to an AC power by an operation of a switching element, A first induction heating coil and a second induction heating coil which are heated and connected in parallel with each other and a first switching device and a second switching device which switch the first induction heating coil and the second induction heating coil to be connected to the inverter respectively And when at least one of the first switching element and the second switching element is turned on or off, the gate signal of the inverter switching element is disabled.

According to the embodiment of the present invention, the switching element for operating the induction heating coil is switched to zero voltage so that it can be efficiently driven. Particularly, it is possible to reduce the power loss at the time of switching and further increase the lifetime of the circuit element.

On the other hand, when at least two induction heating coils to be connected in parallel among a plurality of induction heating coils are heated at the same time, the alternating current power supplied to each induction heating coil is supplied from different inverters so that power can be supplied efficiently The induction heating cooker can be operated.

On the other hand, since the heating portion under the heating plate is used, there is an advantage that there is no flame and the stability is high.

In addition, since the heating portion, in particular, the induction heating coil is not directly heated, the high-frequency current can be continuously supplied, and the energy efficiency and heating time can be shortened.

1 is an external perspective view of an induction heating cooking apparatus according to an embodiment of the present invention.
2 is an example of an internal block diagram of an induction heating cooker.
Figs. 3 to 4 are views referred to explain the operation of the induction cooking apparatus of Fig.
Fig. 5 is an example of an internal block diagram of the induction heating cooking apparatus of Fig.
6 is another example of an internal block diagram of the induction heating cooking appliance of FIG.
FIG. 7 is a view showing the arrangement of the heating unit of FIG. 1 and the induction heating coil of FIG. 5;

Hereinafter, the present invention will be described in detail with reference to the drawings.

The suffix "module" and " part "for components used in the following description are given merely for convenience of description, and do not give special significance or role in themselves. Accordingly, the terms "module" and "part" may be used interchangeably.

1 is an external perspective view of an induction heating cooking apparatus according to an embodiment of the present invention.

Referring to FIG. 1, an induction cooking apparatus 100 according to an embodiment of the present invention includes a heating plate 110, a first heating unit 130, a second heating unit 150, a third heating unit 170, an operation unit 180, and a display unit 190. [

The heating plate 110 is a casing of the induction heating cooker 100 and is disposed on each heating portion. The heating plate 110 can be formed of various materials such as ceramics and tempered glass.

A cooking vessel is disposed above the heating plate 110. In particular, when the cooking vessel 195 is disposed on at least one of the heating units 130, 150, and 170 to be described later, it is heated by the induction heating principle.

The first heating unit 130 includes a plurality of induction heating coils and resonance capacitors (not shown). In the drawing, it is exemplified that the first induction heating coil Lr1 and the fourth induction heating coil Lr4 are provided. Among them, the fourth induction heating coil Lr4 is disposed on the outer periphery of the first induction heating coil Lr1 . In addition, it is also possible that the first induction heating coil and the second induction heating coil are arranged in parallel or the like.

When an alternating current, particularly a high frequency alternating current, flows through the first induction heating coil Lr1 while the cooking vessel 195 is raised on the first heating section 130, particularly the first induction heating coil Lr1, A magnetic field is generated in the first induction heating coil Lr1 by the resonance caused by the first induction heating coil Lr1 and the resonant capacitor (not shown) The eddy currents are induced in the first and second electrodes. Joule heat is generated in the resistance component of the cooking vessel by the eddy current so that the cooking vessel is heated.

On the other hand, when the cooking container 195 is raised not only on the first induction heating coil Lr1 but also on the fourth induction heating coil Lr4, the first induction heating coil Lr1 and the fourth induction heating coil Lr4 A high frequency alternating current flows and the cooking vessel 195 is heated by the eddy current as described above.

The second heating unit 150 includes a second induction heating coil Lr2 and a resonance capacitor (not shown). When the high-frequency alternating current flows in the state where the cooking container 195 is raised on the second heating section 150, particularly the second induction heating coil Lr2, the high-frequency alternating current flows in the cooking container 195 by the eddy current as described above, Is heated.

The third heating unit 170 includes a third induction heating coil Lr3 and a resonance capacitor (not shown). When the high-frequency alternating current flows in the state where the cooking container 195 is raised on the third heating section 170, particularly the third induction heating coil Lr3, the cooking container 195 is heated by the eddy current as described above, Is heated.

The operation unit 180 causes the induction cooking appliance 100 to operate according to an operation by the user. For example, by operating the user, at least one of the first heating unit 130, the second heating unit 150, and the third heating unit 170 should be heated, or the first heating unit 130, It is possible to determine to which of the first induction heating coil Lr1 and the fourth induction heating coil Lr4 the current is supplied or the operation time selection or temperature selection of each heating part.

The operating unit 180 may be provided for each of the heating units 130, 150, and 170 as shown in FIG.

The display unit 190 displays the overall operation state of the induction heating cooking apparatus 100. [ Whether or not each of the heating units 130, 150 and 170 is being operated, the temperature of the cooking apparatus 195 being heated, and the like are displayed.

In addition to the induction heating cooking apparatus 100 according to the embodiment of the present invention, a radiant heat cooking apparatus uses a heating unit under the heating plate 110, similarly to the induction heating cooking apparatus 100, There is no flame, and stability is high. However, since the temperature of the heating section itself rises according to the radiant heating system, on / off control is required to protect the heating section.

However, since the induction heating cooking appliance 100 according to the embodiment of the present invention uses the principle of induction heating by a high frequency, the heating portion, in particular, the induction heating coil is not directly heated so that the high- So that the energy efficiency and the heating time can be shortened.

Meanwhile, since induction heating is efficiently performed in the case of a magnetic substance containing cooking utensil including a metal component, the induction heating cooking appliance 100 is designed so that heating can be performed even in the case of a non-magnetic cooking vessel (Not shown) may be additionally provided. The electrothermal heating unit (not shown) may be disposed in at least one of the heating units 130, 150, and 170. In addition, the induction heating cooking apparatus 100 may further include a load detecting unit (not shown) for detecting the type of the cooking vessel.

2 is an example of an internal block diagram of an induction heating cooker.

The induction heating cooking apparatus 200 according to an embodiment of the present invention includes a converter 210, a reactor L, a smoothing capacitor C, an inverter 220, Switching devices S1 to S2, first and second induction heating coils Lr1 to Lr1, and first and second resonant capacitors Cr1 to Cr2. The controller may further include a controller (not shown), a temperature sensing unit (not shown), an input current detector (not shown), and the like.

The converter 210 receives the commercial AC power source 205 and converts it into DC power and outputs it. For example, the converter 210 includes a diode element, and can output a rectified power from the diode element to a DC power source.

Meanwhile, the converter 210 may include a diode element and a switching element, and may output a DC power source that is converted according to the switching operation of the switching element and the rectifying characteristic of the diode element.

Hereinafter, the converter 210 is mainly composed of a diode element instead of a switching element.

On the other hand, the commercial AC power source 205 may be a single-phase AC power source or a three-phase AC power source. In the case of a single-phase AC power source, the converter 210 may include four diode elements in the form of a bridge. In the case of a three-phase AC power source, the converter 210 may include six diode elements.

The reactors L are respectively connected to one ends of the converters 210 and accumulate the energy of the AC components to remove the harmonic current components or the noise components.

The smoothing capacitor C is connected to the output terminal of the converter 210. It is assumed that the reactor L is disposed between the capacitor and the converter 210 in the drawing.

The smoothing capacitor C smoothes the rectified power output from the converter 210 to the DC power. Hereinafter, the output stage of the converter 210 is referred to as a dc stage. The smoothed direct current voltage of the dc stage is applied to the inverter 220.

The inverter 220 includes an upper arm switching element Sa and a lower arm switching element S'a that are connected in series with each other and the smoothed direct current power is converted to an alternating current power of a predetermined frequency by on / Conversion.

Diodes may be connected in anti-parallel to each switching element Sa, S'a. In addition, the snubber capacitors may be connected in parallel to the switching elements Sa and S'a.

The switching elements Sa and S'a in the inverter 220 are turned on / off based on a switching control signal from a control unit (not shown). At this time, the switching elements Sa and S'a may operate complementarily with each other.

The first induction heating coil Lr1 and the second induction heating coil Lr2 are connected in parallel to form a pair. On the other hand, the first resonance capacitor Cr1 and the second resonance capacitor Cr2 may be connected to the first induction heating coil Lr1 and the second induction heating coil Lr2, respectively, for resonance. High frequency AC power is supplied to each of the induction heating coils Lr1 and Lr2 so that heating can be induced according to the above-described induction heating principle. At this time, the switching elements S1 and S2 for determining the operation of the induction heating coils Lr1 and Lr2 may be connected to the first induction heating coil Lr1 and the second induction heating coil Lr2, respectively.

On the other hand, the control unit (not shown) can control the operation of the switching device Sa.S'a in the inverter 220 and the first to second switching devices S1 to S2 for operating the induction heating coils have.

In particular, for controlling the inverter 220, a switching control signal according to the pulse width modulation (PWm) method can be output. When the switching element in the inverter 220 is an insulated gate bipolar transistor (IGBT), a gate drive control signal according to a pulse width modulation (PWm) scheme can be outputted.

 On the other hand, the control unit (not shown) includes a temperature sensing unit (not shown) for sensing the temperature in the vicinity of each induction heating coil and an input current detecting unit (not shown) for detecting the input current from the commercial AC power supply The operation of the entire induction heating cooking apparatus 100 may be stopped.

Figs. 3 to 4 are views referred to explain the operation of the induction cooking apparatus of Fig.

In the induction heating cooking appliance 200 of FIG. 2, by using a plurality of induction heating coils Lr1 and Lr2 connected in parallel to one inverter 220, the energy efficiency is improved. In particular, when any one of the coils is heated and a maximum output is required, all of the induction heating coils Lr1 and Lr2 are operated. That is, the first and second switching elements S1 and S2 are turned on.

3 shows a state in which the first switching device S1 and the second switching device S2 are turned on during the first period T1 and the second switching device S2 is turned on after a predetermined period T, Is turned off. Thereby, the first induction heating coil Lr1 and the second induction heating coil Lr2 operate during the first period T1, and only the first induction heating coil Lr1 operates during the second period T2 do.

On the other hand, when the second switching device S2 is turned off, the zero voltage zero current switching operation can reduce the power loss during the switching and further increase the lifetime of the circuit device. do.

To this end, in the embodiment of the present invention, the operation of the inverter switching device in the inverter is switched so that zero voltage or zero current switching occurs when the first switching device S1 or the second switching device S2 is turned on or off . Figure 4 illustrates this.

4 shows a state in which the first switching device S1 or the second switching device S2 is turned on or off during a certain period T of the inverter switching device Sa or S'a in the inverter 220 It is illustrated that the gate signal is disabled. In the following description, it is assumed that the inverter switching device is a sag-lock switching device Sa.

First, when the first switching device S1 and the second switching device S2 are turned on at the same time during the first period T1, the control unit (not shown) And instantaneously disables the gate driving signal Si. Whereby zero voltage switching is performed. Therefore, when the first switching device S1 and the second switching device S2 are turned on, the power consumption is reduced.

On the other hand, the disable period of the gate drive signal Si may be longer than the dead time period of the upper arm switch. In the drawing, the period T1a is exemplified.

Next, after the disable period, the gate drive signal Si is switched to enable. The first switching device S1 and the second switching device S2 maintain the on state. Therefore, both the first induction heating coil Lr1 and the second induction heating coil Lr2 operate.

Next, immediately before the turn-off of the second switching element S2, the gate driving signal Si is again switched to disable. On the other hand, the disable period of the gate drive signal Si may be longer than the dead time period of the upper arm switch. In the drawing, the period T1b is exemplified.

Then, the second switching element S2 is turned off, and after the period T2a, the gate driving signal Si is switched back to enable. When the second switching element S2 is turned off, zero voltage switching is performed, so that power consumption is reduced. The first switching device S1 maintains the on state. Therefore, only the first induction heating coil Lr1 operates.

Next, immediately before the first switching device S1 is turned off, the gate driving signal Si is again switched to disable. On the other hand, the disable period of the gate drive signal Si may be longer than the dead time period of the upper arm switch. In the drawing, the period T2b is exemplified.

As described above, when the switching element S1 or S2 is turned on or off, the driving signal of the switching element in the inverter 220 is temporarily disabled, so that the zero voltage switching operation of the switching element is enabled So that the switching loss can be reduced. The lifetime of the device can be increased.

Fig. 5 is an example of an internal block diagram of the induction heating cooking apparatus of Fig.

The induction heating cooking apparatus 500 according to an embodiment of the present invention includes a first converter 510, a second converter 515, a first reactor L1, a second reactor L2 A first smoothing capacitor C1, a second smoothing capacitor C2, a first inverter 520, a second inverter 525, a power source selecting unit 530, first to fourth switching elements S1 to S4 ), First to fourth induction heating coils (Lr1 to Lr4), and first to fourth resonance capacitors (Cr1 to Cr4). The controller may further include a controller (not shown), a temperature sensing unit (not shown), an input current detector (not shown), and the like.

The induction heating cooking apparatus 500 of FIG. 5 is different from the induction heating cooking apparatus 200 of FIG. 2 in that a plurality of converters 510 and 515, a plurality of inverters 520 and 525, a plurality of reactors L1 and L2, Smoothing capacitors C1 and C2, and the like. A description thereof will be omitted with reference to FIG.

Meanwhile, the operations of the first inverter 520 and the second inverter 525 can be performed separately. That is, it is possible to generate and output the first high frequency AC power source and the second high frequency AC power source, respectively.

The first induction heating coil Lr1 and the second induction heating coil Lr2 are connected in parallel to form a pair. On the other hand, the first resonance capacitor Cr1 and the second resonance capacitor Cr2 may be connected to the first induction heating coil Lr1 and the second induction heating coil Lr2, respectively, for resonance. High frequency AC power is supplied to each of the induction heating coils Lr1 and Lr2 so that heating can be induced according to the above-described induction heating principle. At this time, the switching elements S1 and S2 for determining the operation of the induction heating coils Lr1 and Lr2 may be connected to the first induction heating coil Lr1 and the second induction heating coil Lr2, respectively.

The third induction heating coil Lr3 and the fourth induction heating coil Lr4 are connected in parallel to form a pair. On the other hand, the third resonance capacitor Cr3 and the fourth resonance capacitor Cr4 may be connected to the third induction heating coil Lr3 and the fourth induction heating coil Lr4, respectively, for resonance. High frequency AC power is supplied to each of the induction heating coils Lr3 and Lr4 so that heating can be induced in accordance with the above-described induction heating principle. At this time, the switching elements S3 and S4 for determining the operation of the induction heating coils Lr3 and Lr4 may be connected to the third induction heating coil Lr3 and the fourth induction heating coil Lr4, respectively.

On the other hand, the operation of the first to fourth switching elements S1 to S4 can be performed by zero voltage switching as described above. That is, when at least one of the first to fourth switching devices S1 to S4 is turned on or off, the control unit (not shown) temporarily disables the gate driving signal Si applied to the inverters 520 and 525 Disable. As a result, the power consumption in the operation of the switching element is reduced.

Particularly, when the AC power supplied to each switching element is determined in conjunction with the operation of the power source selecting unit 530 to be described later, the gate driving signal Si of the inverter that supplies the AC power is momentarily disabled ).

The power source selection unit 530 selects the first AC power from the first inverter 520 and the second AC power from the second inverter 525 when both the first induction heating coil Lr1 and the second induction heating coil Lr2 are operated, And supplies the selected first AC power to the first induction heating coil Lr1 so that the second AC power is selected and supplied to the second induction heating coil Lr2.

For example, the first induction heating coil Lr1 may be controlled to be supplied with the first alternating current power, and the second induction heating coil Lr2 may be controlled to be supplied with the second alternating current power.

Thus, when at least two of the plurality of induction heating coils connected in parallel to the same inverter are to be turned on, the AC power applied to each induction heating coil can be separated. That is, the AC power can be supplied from different inverters. As a result, the same AC power is not supplied from the same inverter, power is not reduced, and AC power can be supplied stably.

When all the third induction heating coil Lr3 and the fourth induction heating coil Lr4 are operated, the power source selection unit 530 selects the first AC power source from the first inverter 520 and the second AC power source from the second inverter 525 and supplies the selected second AC power to the third induction heating coil Lr3 so that the first alternating current power is selected and supplied to the fourth induction heating coil Lr4 .

For example, the third induction heating coil Lr3 may be controlled to be supplied with the second alternating current power, and the fourth induction heating coil Lr4 may be controlled to be supplied with the first alternating current power.

To this end, the power source selection unit 530 may include a relay device. The figure illustrates that the first relay element R1 and the second relay element R2 are provided.

The first relay element R1 is arranged between the inverters 520 and 225 and the second induction heating coil Lr2 so that the second induction heating coil Lr2 is connected between the first inverter 520 and the second inverter 525 And performs a relay operation to be connected to any one of them.

The second relay element R2 is disposed between the inverters 520 and 225 and the fourth induction heating coil Lr4 so that the fourth induction heating coil Lr4 is disposed between the first inverter 520 and the second inverter 525 And performs a relay operation to be connected to any one of them.

On the other hand, the control of the relay operation of the first relay element R1 and the second relay element R2 can be performed by a control signal of a control section (not shown).

6 is another example of an internal block diagram of the induction heating cooking appliance of FIG.

Referring to the drawings, an induction heating cooking appliance 600 according to an embodiment of the present invention is substantially the same as the induction heating cooking appliance 500 of FIG. Only the differences will be described below.

The induction cooking apparatus 600 of FIG. 6 differs from the induction cooking apparatus 500 of FIG. 5 in that one dc stage is used. That is, the first inverter 620 and the second inverter 625 share one converter 610, a reactor L, and a smoothing capacitor C, respectively.

The first to fourth switching elements S1 to S4 and the first to fourth induction heating coils Lr1 to Lr4 and the first to fourth resonance capacitors Cr1 to Cr4 . The controller may further include a controller (not shown), a temperature sensing unit (not shown), an input current detector (not shown), and the like.

As described above, the power source selecting unit 630 can be configured such that the first induction heating coil Lr1 and the second induction heating coil Lr2 are both connected in parallel to each other by using a single dc stage but using separate inverters 620 and 325. [ One of the first AC power from the first inverter 620 and the second AC power from the second inverter 625 is selected and supplied to the first induction heating coil Lr1, One can be controlled to be supplied to the second induction heating coil Lr2.

The power source selection unit 630 selects the first AC power from the first inverter 620 and the second AC power from the second inverter 630 when the third induction heating coil Lr3 and the fourth induction heating coil Lr4 are both operated. 625 may be selected to be supplied to the third induction heating coil Lr3 and the other to be supplied to the fourth induction heating coil Lr4.

Thereby, even when a plurality of induction heating coils are operated, the power is not reduced, and the AC power supply can be supplied stably.

On the other hand, the operation of the first to fourth switching elements S1 to S4 can be performed by zero voltage switching as described above. That is, when at least one of the first to fourth switching devices S1 to S4 is turned on or off, the control unit (not shown) temporarily disables the gate driving signal Si applied to the inverters 620 and 625 Disable. As a result, the power consumption in the operation of the switching element is reduced.

FIG. 7 is a view showing the arrangement of the heating unit of FIG. 1 and the induction heating coil of FIG. 5;

Referring to FIG. 7, the first heating unit 130 includes a first induction heating coil Lr1 and a fourth induction heating coil Lr4. The second heating unit 150 includes a second induction heating coil Lr2 and the third heating unit 170 includes a third induction heating coil Lr3.

It is preferable that the fourth induction heating coil Lr4 in the first heating portion 130 is disposed on the outer periphery of the first induction heating coil Lr1. Since the first heating unit 130 is provided with two induction heating coils, it is possible to heat the cooking vessel with higher power than the other heating units 150 and 170. For example, the cooking vessel can be heated with approximately twice the power.

In the arrangement shown in Fig. 7, when only the first inductive heating coil Lr1 in the first heating part 130 is operated, only the first switching device S1 is turned on. Thereby, the first AC power supply i1 from the first inverter 520 is supplied to the fixed first induction heating coil Lr1.

On the other hand, when the fourth induction heating coil Lr4 is also operated, the fourth switching device S4 is also turned on, and unlike the first induction heating coil Lr1, the fourth induction heating coil Lr4, The relay operation is performed so that the second relay element R2 in the power source selection unit 530 is connected to the second inverter 525 so that the second AC power source i2 from the inverter 525 is supplied.

On the other hand, when the second induction heating coil Lr2 in the second heating unit operates and the first induction heating coil Lr1 in the first heating unit operates, the first switching device S1 and the second switching device S2 are turned on. Thus, the first AC power source i1 from the first inverter 520 is supplied to the fixed first induction heating coil Lr1. On the other hand, the first relay element R1 in the power source selection unit 530 is controlled so that the second alternating-current power source i2 from the second inverter 525 is supplied to the variable second inductive heating coil Lr2, The relay operation is performed so as to be connected to the bus 525.

On the other hand, when the third induction heating coil Lr3 in the third heating section operates and the first induction heating coil Lr1 in the first heating section operates, since the induction heating coils Lr1 and Lr3 are all fixed , The first switching device S1 and the third switching device S3 may be turned on regardless of the operation of the power source selecting unit 530. [ The first AC power source i1 from the first inverter 520 is supplied to the first induction heating coil Lr1 and the second AC power source i2 from the second inverter 520 is supplied to the third induction heating coil Lr3, And an AC power source i2 is supplied.

On the other hand, the third induction heating coil Lr3 in the third heating part operates and the fourth induction heating coil Lr4 in the first heating part may operate simultaneously. In this case, the third switching device S3 and the fourth switching device S4 are turned on. Thus, the second AC power supply i2 from the second inverter 525 is supplied to the fixed third induction heating coil Lr3. The second relay element R2 in the power source selection unit 530 is connected to the first inverter 520 so that the first AC power source i1 from the first inverter 520 is supplied to the fourth induction heating coil Lr4, (520).

On the other hand, when all the induction heating coils Lr1 to Lr4 operate, all the switching elements S1 to S4 are turned on. In this case, the respective AC power sources i1 and i2 from the respective inverters 520 and 525 are distributed to be supplied to the induction heating coils Lr1 to Lr4. The first relay element R1 in the power source selection unit 530 is operated to be connected to the first inverter 520 and the second relay element R2 is connected to the second inverter 525 A relay operation can be performed.

As described above, when at least one of the first to fourth switching elements S1 to S4 is turned on or off, the controller (not shown) controls the gate driving signal applied to the inverters 520 and 525 (Si) is instantaneously disabled. As a result, the power consumption in the operation of the switching element is reduced.

The induction heating cooker according to the present invention is not limited to the configuration and the method of the embodiments described above but can be applied to all or some of the embodiments selectively And may be configured in combination.

Meanwhile, the operation method of the induction heating cooking apparatus of the present invention can be implemented as a processor readable code on a processor-readable recording medium provided in the induction heating cooking apparatus. The processor-readable recording medium includes all kinds of recording apparatuses in which data that can be read by the processor is stored.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the present invention.

Claims (9)

An inverter having inverter switching elements, the inverter converting the DC power to a first AC power and supplying the DC power to the first AC power by the operation of the switching element;
A first induction heating coil and a second induction heating coil heated by the first AC power source and connected in parallel with each other; And
And a first switching element and a second switching element for switching the first induction heating coil and the second induction heating coil to be connected to the inverter, respectively,
Wherein the gate signal of the inverter switching device is disabled when at least one of the first switching device and the second switching device is turned on or off. The method according to claim 1,
Wherein the gate signal of the inverter switching device is enabled after at least one of the first switching device and the second switching device is turned on or off. The method according to claim 1,
Wherein the gate signal of the inverter switching device is disabled for at least a dead time period when at least one of the first switching device and the second switching device is turned on or off. The method according to claim 1,
A second inverter which includes inverter switching elements and converts the DC power into a second AC power by the operation of the switching element;
A third induction heating coil and a fourth induction heating coil heated by the second AC power source and connected in parallel with each other; And
A third switching element and a fourth switching element for switching the third induction heating coil and the fourth induction heating coil to be respectively connected to the second inverter,
Wherein the gate signal of the second inverter switching element is disabled when at least one of the third switching element and the fourth switching element is turned on or off. 5. The method of claim 4,
Wherein the gate signal of the second inverter switching element is enabled after at least one of the third switching element and the fourth switching element is turned on or off. 5. The method of claim 4,
Wherein the gate signal of the second inverter switching device is disabled during at least a dead time period when at least one of the third switching device and the fourth switching device is turned on or off. 5. The method of claim 4,
A first heating unit having the first induction heating coil and the fourth induction heating coil, the fourth induction heating coil being disposed on an outer periphery of the first induction heating coil;
A second heating unit including the second induction heating coil; And
And a third heating unit including the third induction heating coil. 5. The method of claim 4,
The first AC power source and the second AC power source are selected and supplied to the first induction heating coil when both the first induction heating coil and the second induction heating coil are operated And a power selection unit for selecting the second AC power supply and supplying the selected second AC power to the second induction heating coil. 9. The method of claim 8,
The power-
The second AC power supply is selected among the first AC power supply and the second AC power supply and supplied to the third induction heating coil when both the third induction heating coil and the fourth induction heating coil are operated , And the first AC power source is selected and supplied to the fourth induction heating coil.

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