Induction heating device and method for controlling induction heating device

Patent metadata

Field	Value
Publication number	US-2023103228-A1
Application number	US-202117908962-A
Country	US
Kind code	A1
Filing date	Feb 23, 2021
Priority date	Mar 4, 2020
Publication date	Mar 30, 2023
Grant date	—

Abstract

The present disclosure relates to an induction heating device and a control method thereof. An induction heating device of one embodiment may comprise: an inverter circuit supplying electric currents to a working coil; a driving circuit supplying a switching signal to the inverter circuit, based on a control signal; an output detector detecting an output of the working coil; and a controller setting on-time of the working coil based on a current output of the working coil and controlling the output of the working coil, in a low-level operation in which a target output is equal to or less than a predetermined value.

First claim

1 . An induction heating device, comprising:
an inverter circuit supplying electric currents to a working coil; a driving circuit providing a switching signal to the inverter circuit, based on a control signal; an output detector detecting an output of the working coil; and a controller setting on-time of the working coil based on a current output of the working coil and controlling the output of the working coil, in a low-level operation in which a target output is equal to or less than a predetermined value.

2 . The induction heating device of claim 1 , wherein the controller sets an operation frequency of the inverter circuit to an upper limit frequency, and adjusts the on-time of the working coil and controls the output of the working coil, in the low-level operation.

3 . The induction heating device of claim 2 , wherein when the current output of the working coil is equal to or less than a predetermined critical output, the controller determines the on-time, based on the target output and the critical output.

4 . The induction heating device of claim 3 , wherein the controller applies a value calculated by dividing the target output by the critical output to an on-off period and determines the on-time.

5 . The induction heating device of claim 2 , wherein when the current output of the working coil is greater than a predetermined critical output, the controller determines the on-time, based on the target output and the current output.

6 . The induction heating device of claim 5 , wherein the controller applies a value calculated by dividing the target output by the current output to an on-off period and determines the on-time.

7 . The induction heating device of claim 1 , wherein the controller reduce an on-off period while maintaining a ratio of the on-time to off-time in one period.

8 . The induction heating device of claim 7 , wherein when the determined on-time is equal to or less than a predetermined value, the controller divide the on-off period by an integer while maintaining the ratio of the on-time to the off-time.

9 . A control method of an induction heating device, comprising:
determining whether the operation mode of the induction heating device is a low-level operation in which a target output is equal to or less than a predetermined value; detecting an output of a working coil; and setting on-time of the working coil, based on a current output of the working coil, and controlling the output of the working coil.

10 . The control method of claim 9 , controlling the output of the working coil, comprising:
setting an operation frequency of an inverter circuit to an upper limit frequency; and comparing the current output of the working coil with a predetermined critical output and setting a determination method of the on-time.

11 . The control method of claim 10 , wherein controlling the output of the working coil, comprising:
determining the on-time, based on the target output and the critical output, when the current output of the working coil is equal to or less than a predetermined critical output.

12 . The control method of claim 11 , wherein controlling the output of the working coil comprises applying a value calculated by dividing the target output by the critical output to an on-off period and determining the on-time, when the current output of the working coil is equal to or less than a predetermined critical output.

13 . The control method of claim 10 , wherein controlling the output of the working coil, comprising:
determining the on-time, based on the target output and the current output, when the current output of the working coil is greater than the predetermined critical output; and applying a value calculated by dividing the target output by the current output to an on-off period and determining the on-time, when the current output of the working coil is greater than the predetermined critical output.

14 . The control method of claim 9 , wherein the control method further comprises reducing an on-off period while maintaining a ratio of the on-time and off-time in one period.

15 . The control method of claim 14 , wherein reducing an on-off period comprises dividing the on-off period by an integer, while maintaining the ratio of the on-time and the off-time, when the determined on-time is equal to or less than a predetermined value.

Assignees

• Lg Electronics Inc

Inventors

• Park Wongyu
• Yoon Bada
• Kang John

Classifications

• H05B6/062 Primary

  for cooking plates or the like · CPC title

• H05B6/1209

  induction cooking plates or the like and devices to be used in combination with them · CPC title

• H05B6/04

  Sources of current · CPC title