Output control method through duty control of integrated half-bridge inverter electric range

Abstract

The present invention relates to an output control method for minimizing coupling noise during low-level output of an integrated half-bridge inverter electric range, and more specifically, to an output control method for minimizing coupling noise during low-level output of an integrated half-bridge inverter electric range through duty control of the on-time of an upper IGBT element and a lower IGBT element. The output control method of an integrated half-bridge inverter electric range according to the present invention includes an input detection stage, a normal output stage, and a duty output stage. The input detection stage uses a microcontroller of the integrated half-bridge inverter electric range to detect the input of the output button of the electric range, which is set in stages according to the intensity of the heat. The normal output stage repeatedly turns the lower IGBT element and the upper IGBT element on and off with the same on time so that the output of the input output button is produced when the input detected in the input detection stage is greater than or equal to a reference heat value. The duty output stage performs duty control so that the output of the output button is produced at a predetermined level of reference power when the input detected in the input detection stage is less than the reference heat value. Here, the duty output step comprises a same time interval in which the on-time of the upper IGBT element and the lower IGBT element are the same, and a different time interval in which the on-time of the upper IGBT element and the lower IGBT element are the same, and alternately repeats the same time interval and the different time interval.

Description

Technology Field

[0001] The present invention relates to an output control method for minimizing coupling noise during low-level output of an integrated half-bridge inverter electric range, and more specifically, to an output control method for minimizing coupling noise during low-level output of an integrated half-bridge inverter electric range through duty control of the on-time of an upper IGBT element and a lower IGBT element. Background Technology

[0002] Induction electric cooktops heat cookware using electromagnetic induction. When current is sent to the working coil located beneath the cooktop, a magnetic field is generated, and as this magnetic field passes through the cookware placed on the cooktop, it creates eddy currents. These eddy currents transfer heat to the cookware itself, thereby facilitating cooking.

[0003] In electric ranges using an integrated half-bridge inverter, high power is supplied during high-heat output, while low power is supplied during low-heat output. In this case, high power is supplied continuously during high-heat output, but during low-heat output, due to feedback issues, low power is not supplied continuously; instead, a stop section is introduced where a constant reference power higher than the low power is temporarily supplied before output ceases, thereby matching the low-power output.

[0004] Therefore, when the electric range is at low power output, the power supply section and the power supply stop section are repeated, so the power start point is continuously repeated, resulting in a problem where the coupling noise generated at the start of power is prominent. Prior art literature

[0005] Registered Patent No. 10-2418392 (Registration Date: July 4, 2022) Registered Patent No. 10-2453862 (Registration Date: October 6, 2022) Registered Patent No. 10-2525461 (Registration Date: April 20, 2023) The problem to be solved

[0006] The present invention aims to solve the above-mentioned problems. The present invention aims to provide an output control method capable of minimizing the generation of coupled noise during low-heat output of an integrated half-bridge inverter electric range. means of solving the problem

[0007] The output control method of an integrated half-bridge inverter electric range according to the present invention includes an input detection stage, a normal output stage, and a duty output stage. The input detection stage uses a microcontroller of the integrated half-bridge inverter electric range to detect the input of the output button of the electric range, which is set in stages according to the intensity of the heat. The normal output stage repeatedly turns the lower IGBT element and the upper IGBT element on and off with the same on time so that the output of the input output button is produced when the input detected in the input detection stage is greater than or equal to a reference heat value. The duty output stage performs duty control so that the output of the output button is produced at a predetermined level of reference power when the input detected in the input detection stage is less than the reference heat value. Here, the duty output step comprises a same time interval in which the on-time of the upper IGBT element and the lower IGBT element are the same, and a different time interval in which the on-time of the upper IGBT element and the lower IGBT element are the same, and alternately repeats the same time interval and the different time interval.

[0008] In addition, in the output control method of the integrated half-bridge inverter electric range described above, it is preferable that the on-time of the lower IGBT element in the other time interval of the duty output stage is greater than the on-time of the lower IGBT element. Effects of the invention

[0009] According to the present invention, continuous output is possible through a duty output step during low-heat output. Therefore, by reducing the output starting point, coupling noise generated at the output starting point can be minimized. Brief explanation of the drawing

[0010] FIG. 1 is an embodiment of an output control method for an IGBT device according to the present invention. FIG. 2 is the frequency waveform of the embodiment of FIG. 1 Figure 3 shows the frequency waveform of a different time interval in Figure 2. Figure 4 is the frequency waveform of the same time interval in Figure 2. Specific details for implementing the invention

[0011] An embodiment of the output control method of an integrated half-bridge inverter electric range according to the present invention will be described with reference to FIGS. 1 to 4.

[0012] The output control method of an integrated half-bridge inverter electric range according to the present invention includes an input detection step (S11), a normal output step (S13), and a duty output step (S15).

[0013] When high heat is required during the output of an electric range, high power is output, and when low heat is required, low power is output. In this case, high power is output continuously in the case of high heat, but in the case of low heat, since the feedback signal is not high during low power output, low power is not output continuously; instead, a stop section is introduced to match the total output power by outputting a constant level of power higher than the required low power for a short moment and then stopping the next output. Therefore, in the case of low heat, since a constant level of power is supplied repeatedly, the output start point is continuously repeated. Consequently, coupling noise occurring at the output start point was repeatedly generated. In the present embodiment, to solve this problem, control is performed using a duty output stage (S15) when low heat is output.

[0014] First, the input detection step (S11) uses a microcontroller of the integrated half-bridge inverter electric range to detect the input of the output button of the electric range, which is set in stages according to the intensity of the heat. That is, it detects whether a low heat output or a high heat output is selected from the output button.

[0015] Generally, the output button on an electric range can be adjusted from 1 to 9 depending on the heat intensity. For example, if it is 4 or higher, it is considered high heat, and if it is 3 or lower, it is considered low heat. Therefore, in the input detection step (S11), it detects whether the high heat output button is pressed or the low heat output button is pressed.

[0016] The normal output step (S13) repeatedly turns the lower IGBT element and the upper IGBT element on and off with the same on time so that when the input detected in the input detection step (S11) is greater than or equal to the reference heat value, the output of the input output button is produced. In this case, high heat is continuously output to provide high heat to the container. Thus, normal output control is executed. In the case of this embodiment, the normal output step (S13) is performed when a heat value of 4 or higher is input from the output button.

[0017] The duty output step (S15) performs a duty output step that controls the duty so that the output selected from the output button is output at a predetermined level of reference power when the input detected in the input detection step (S11) is smaller than the reference power value. In the case of this embodiment, the duty output step is performed when a power value of 1 to 3, which is smaller than the reference power value of 4, is pressed on the output button.

[0018] Here, the duty output stage is provided with a different time interval (10) and an identical time interval (30), and the different time interval (10) and the identical time interval (30) are repeated alternately.

[0019] The different time interval (10) is a interval where the on time (3) of the upper IGBT element and the on time (1) of the lower IGBT element are different, and the same time interval (30) is a interval where the on time (3) of the upper IGBT element and the on time (1) of the lower IGBT element are the same.

[0020] The upper IGBT device generates a magnetic field by passing current through the inductor, inducing eddy currents in a container placed within that field. At this time, energy is stored in the inductor. That is, when the upper IGBT device is turned on, power is connected to the inductor, causing current to flow. Since the inductor is in the form of a coil, it forms a strong magnetic field when current flows. This magnetic field surrounds the container, inducing eddy currents inside it. The eddy currents strike the resistance of the container, generating heat and heating the container. Simultaneously, the energy generated during this process is stored in the inductor.

[0021] When the upper IGBT is turned off and the lower IGBT is turned on, the energy stored in the inductor is rapidly released. This energy causes a strong current to flow through the container, heating it up. At this time, the energy stored in the inductor is released toward the nearest container. Therefore, the energy stored in the inductor is rapidly released toward the container, heating it up.

[0022] Furthermore, dead time prevents the upper and lower IGBTs from turning on simultaneously. This prevents current conflicts and ensures stable operation.

[0023] Therefore, the duty output stage provides power higher than that providing low-power output, and by adjusting the on-time of the upper IGBT element and the lower IGBT element, low-power output can be provided. In this case, since the different time interval (10) and the same time interval (30) are repeated, there is no interval where the output is stopped. Therefore, the combined noise generated at the start of the output can be reduced. Explanation of the symbols

[0024] 1 : Bottom IGBT device on-time 3 : Top IGBT device on-time 5 : Dead time 10 : Different time interval 30 : Same time interval

Claims

Claim 1 An output control method for an integrated half-bridge inverter electric range, comprising: an input detection step for detecting an input of an output button of the electric range set in stages according to the intensity of the heat power using a microcontroller of the integrated half-bridge inverter electric range; a normal output step for repeatedly turning on and off an upper IGBT element and a lower IGBT element with the same on-time so that the output of the input output button is produced when the input detected in the input detection step is greater than or equal to a reference heat power value; and a duty output step for performing duty control so that the output of the output button is produced at a predetermined level of reference power when the input detected in the input detection step is less than the reference heat power value, wherein the duty output step is characterized by having a same time interval in which the on-time of the upper IGBT element and the lower IGBT element are the same, and a different time interval in which the on-time of the upper IGBT element and the lower IGBT element are different, and alternately repeating the same time interval and the different time interval. Claim 2 A method for controlling the output of an integrated half-bridge inverter electric range, wherein, in claim 1, the other time interval of the duty output step is characterized in that the on-time of the lower IGBT element is greater than the on-time of the upper IGBT element.

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