Induction heating method implemented in a device including magnetically coupled inductors
First Claim
1. An induction heating method implemented in a device for heating a metal part, the device including magnetically coupled inductors, each inductor being powered by a dedicated inverter and being connected to a capacitor to form an oscillating circuit, said oscillating circuits having at least approximately the same resonance frequency, each inverter being controlled by a control unit to vary the amplitude and the phase of the current passing through the corresponding inductor and to control the current phase and amplitude, the device also determining an actual temperature profile of said metal part, said method comprising the following steps:
- a) comparing said actual temperature profile with a reference temperature profile and calculating a profile of the reference power density which the heating device must inject into said part in order to achieve said reference temperature profile;
b) from a matrix of impedances determined by knowledge of the electromagnetic relationships linking said inductors with each other and with said part and by knowledge of vector image functions representing the relationships between the current densities created by the inductors and the currents passing through the inductors, calculating target currents which the inverters must produce in order for the currents of the inductors to reach target values of the currents determined for injecting said reference power density profile into said part;
c) determining the currents passing through the inductors in order to compare them with said target values of the currents and to determine current deviations to be corrected, and sending correction instructions to said control units in accordance with said current deviations in order to control the inverters to correct the currents passing through the inductors; and
d) heating the metal part with the corrected currents passing through the inductors with the controlled phases and amplitudes.
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Accused Products
Abstract
Provided is an induction heating method implemented in a device for heating a metal part, the device including magnetically coupled inductors. Oscillating circuits of the device have at least approximately the same resonance frequency, each inverter is controlled by a control unit to vary amplitude and phase of current passing through the corresponding inductor, the device also including a means for determining said current and an actual temperature profile of said part. The method includes: a) comparing said actual temperature profile with a reference temperature profile and calculating a reference power density profile; b) calculating target currents which the inverters must produce in order for the currents of the inductors to reach suitable target values; c) determining the currents passing through the inductors to compare said currents with said target values and determine correction current deviations, and sending correction instructions to said control units in accordance with said current deviations.
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Citations
17 Claims
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1. An induction heating method implemented in a device for heating a metal part, the device including magnetically coupled inductors, each inductor being powered by a dedicated inverter and being connected to a capacitor to form an oscillating circuit, said oscillating circuits having at least approximately the same resonance frequency, each inverter being controlled by a control unit to vary the amplitude and the phase of the current passing through the corresponding inductor and to control the current phase and amplitude, the device also determining an actual temperature profile of said metal part, said method comprising the following steps:
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a) comparing said actual temperature profile with a reference temperature profile and calculating a profile of the reference power density which the heating device must inject into said part in order to achieve said reference temperature profile; b) from a matrix of impedances determined by knowledge of the electromagnetic relationships linking said inductors with each other and with said part and by knowledge of vector image functions representing the relationships between the current densities created by the inductors and the currents passing through the inductors, calculating target currents which the inverters must produce in order for the currents of the inductors to reach target values of the currents determined for injecting said reference power density profile into said part; c) determining the currents passing through the inductors in order to compare them with said target values of the currents and to determine current deviations to be corrected, and sending correction instructions to said control units in accordance with said current deviations in order to control the inverters to correct the currents passing through the inductors; and d) heating the metal part with the corrected currents passing through the inductors with the controlled phases and amplitudes. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
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Specification