Induktionsgenerator und Verfahren mit Oszillationsfrequenzsteuerung

Details

Veröffentlichungs-Nr.

EP4766015

Anmeldetag

18. Dezember 2024

Veröffentlichung

24. Juni 2026

Rechtsraum

EP

IPC

H05B6/06, H02M7/48

Abstract

An induction generator (2) is configured for driving an induction circuit (4), in particular for driving an induction coil of an induction hob (30). The induction generator (2) comprises: a power supply unit (8) configured to provide an input voltage (Vi) with respect to a common voltage (Vc); a driving unit (10) configured to provide a first and a second transistor driving voltage (Vg1, Vg2); a half-bridge arrangement (12) comprising a first transistor and a second transistor (14, 16) connected in series at a middle node (22), wherein the serially connected first and second transistors (14, 16) are connected between the input voltage (Vi) and the common voltage (Vc), wherein the first transistor driving voltage (Vg1) is applied to the gate of the first transistor (14), and wherein the second transistor driving voltage (Vg2) is applied to the gate of the second transistor (16); a resonance circuit (4) comprising an induction coil element (6) being electrically connected at one end to the middle node (22) and being configured to emit an electromagnetic field when in operation; a control unit (20) having an output configured to supply a control signal to the driving unit (10) and having an input electrically connected to the middle node (22) configured for sensing the middle voltage (Vm) at the middle node. The control unit (20) is configured to apply the control signal at a setpoint frequency to the driving unit (10) such that via the first and second transistor driving voltages (Vg1, Vg2) a temporal switching sequence is implemented where the first transistor (14) is switched on and off and the second transistor (16) is switched on and off with a delay period (To) between switching off the first transistor (14) and switching on the second transistor (16). The control unit is further configured to detect the middle voltage (Vm) and/or the complimentary middle voltage (Vm*); and to evaluate the amplitude of the middle voltage (Vm) or the temporal behavior of the middle voltage (Vm) in relation to the switching off of the first transistor (14) and/or in relation to the switching on of the second transistor (16), and/or to evaluate the amplitude of the complimentary middle voltage (Vm*) or the temporal behavior of the complimentary middle voltage (Vm*) in relation to the switching off of the second transistor (16) and/or in relation to the switching on of the first transistor (14). The control unit is further configured to increase or to decrease or to maintain the setpoint frequency of the switching sequence being applied via the control signal in dependency of the evaluation. Alternatively or additionally the control unit is further configured to increase or to decrease or to maintain an on-time ratio (Ta/Tb or Tb/Ta), where within a switching sequence Ta is the duration of switching on the first transistor (14) and Tb is the duration of switching on the second transistor (16).

Anmelder

Firma

ELECTROLUX APPLIANCES AKTIEBOLAG

Land

🇸🇪 Schweden

Fachgebiete