Electromagnetic heating system, and zero-crossing switched-on detection method and device of switch tube

Abstract

The invention discloses a zero-crossing switched-on detection device of a switch tube in an electromagnetic heating system. The device comprises a current detection circuit for detecting the loop current of a resonant circuit, a pulse detection circuit which processes loop current to output a first pulse signal, a master control unit which is connected to the driving circuit and the pulse detection circuit and comprises a first counter which counts the first pulse signals and increases the switched-on time interval of the switch tube if the counting value of the first counter is larger than a preset value in a preset time such that a driving circuit drives the switch tube to be in zero-crossing switched-on. The zero-crossing switched-on detection device can automatically adjust the switch-on time interval of the switch tube and allow the switch tube to be zero-crossing switched-on, and the energy efficiency of the electromagnetic heating system is improved. The invention also discloses the electromagnetic heating system and a zero-crossing switched-on detection method of the switch tube in the electromagnetic heating system.

Description

technical field [0001] The invention relates to the technical field of household appliances, in particular to a zero-crossing turn-on detection device for a switch tube in an electromagnetic heating system, an electromagnetic heating system and a zero-crossing turn-on detection method for a switch tube in the electromagnetic heating system. Background technique [0002] At present, the circuit scheme of the induction cooker is mainly a single-tube IGBT (Insulated Gate Bipolar Transistor, insulated gate bipolar transistor) scheme. By judging the voltage division value at both ends of the coil disk and the resonant capacitor, the IGBT is flipped and turned on according to the synchronous comparison signal. [0003] However, the IGBT can only be turned on based on empirical values. In order to prevent the IGBT from being turned on ahead of time or lagging behind, the IGBT only works in a very narrow working range, and it is impossible to make corresponding judgments when factors...

AI Technical Summary

Problems solved by technology

[0003] However, the IGBT can only be turned on based on empirical values. In order to prevent the IGBT from being turned on ahead of time or lagging behind, the IGBT only works in a very narrow working range, and it is impossible to make corresponding judgments when factors such as disc spacing, voltage, and pot change, making the IGBT It is easy to work in the leading or lagging state, so that the heat of the IGBT is very large, and because the induction cooker generally has overheating protection, it greatly limits the heating efficiency of the induction cooker, making it difficult to improve energy efficiency

Images