Voltage zero-crossing detection method and device and cooking electric appliance

Abstract

The invention discloses a voltage zero-crossing detection method and device and a cooking electric appliance. The detection method includes the following steps: obtaining timing duration of a timer, wherein the timing duration of the timer corresponds to the time of a half cycle of alternating voltage; receiving an interrupt signal generated when the alternating voltage zero-crosses, and startingthe timer when the interrupt signal generated when the alternating voltage zero-crosses is received; generating an overflow interrupt signal when the timing of the timer ends; and determining that thealternating voltage is negatively zero-crossed according to the overflow interrupt signal to obtain a negative zero-crossing moment of the alternating voltage. Therefore, the moment when the alternating voltage zero-crossing is interrupted is synchronized with a zero-crossing moment of actual alternating voltage, and the problem of inaccurate voltage zero-crossing detection is effectively solved.

Description

technical field [0001] The invention relates to the technical field of voltage zero-crossing detection, in particular to a voltage zero-crossing detection method, a voltage zero-crossing detection device and a cooking appliance with the detection device. Background technique [0002] As we all know, the voltage or current waveform of alternating current starts from zero, gradually rises to the positive maximum value, then drops from the positive maximum value to zero, then reaches the negative maximum value, and then returns to zero point,…. Zero-crossing is the moment when the voltage or current of the alternating current reaches "zero", and the instantaneous voltage or current at this moment is zero. [0003] In electronic control technology, when the switching tube is turned on or off, because the inrush current generated when the switching tube is turned on or off at the zero crossing point is small, the switching tube is usually controlled at the zero crossing point. T...

AI Technical Summary

Problems solved by technology

For this reason, the first object of the present invention is to propose a voltage zero-crossing detection method, which can synchronize the moment when the AC voltage zero-crossing is interrupted with the actual zero-crossing time of the AC voltage, effectively solving the problem of inaccurate voltage zero-crossing detection question

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