Electric cooker and its zero-crossing calibration circuit and zero-crossing calibration method

Abstract

The invention discloses an electric cooking device, a zero-crossing calibration circuit of the electric cooking device, and a zero-crossing calibration method of the electric cooking device. The zero-crossing calibration circuit comprises a zero-crossing detection unit, which outputs a zero-crossing signal through detecting a zero-crossing point of an input AC power source; a resonance voltage detection unit, which is connected to a first node to detect the resonance voltage of the first node; a comparator, with the first input end of the comparator being connected to the resonance voltage detection unit to input resonance voltage, and the second input end of the comparator being connected to a preset power supply; a control unit, with the zero-crossing detection end of the control unit being connected to the zero-crossing detection unit, and the voltage sampling end of the control unit being connected to the output end of the comparator. When detecting that the zero-crossing signal changes from a falling edge to a rising edge through the zero-crossing detection end, the control unit samples comparison result signals of the output terminal of the comparator through the voltage sampling end, determines zero-crossing detection errors when the comparison result signals change and performs correction on the zero-crossing signal.

Description

technical field [0001] The invention relates to the technical field of cooking appliances, in particular to a zero-crossing calibration circuit of an electric cooker, an electric cooker and a zero-crossing calibration method of the electric cooker. Background technique [0002] Electromagnetic induction heating electric cooker has been widely used. For the electromagnetic induction heating control circuit in this type of electric cooker, there is a continuous low-power control method that takes half-wave alternating current as the heating cycle and adopts the method of dropping waves during heating, because the resonance of electromagnetic induction heating needs half-wave alternating current For the frequent start and stop of the cycle, it is necessary to correctly detect and judge the zero-crossing point of the AC power supply. When the zero-crossing point is misjudged, the current noise of the heating and starting of the electric cooker will increase, and the reliability...

AI Technical Summary

Problems solved by technology

When the zero-crossing point is misjudged, the current noise of the heating and starting of the electric cooker will increase, and the reliability of the power switch tube in the circuit will decrease.

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