What is the reason for the slow heating of the induction cooker
1. The capacity of the resonant capacitor becomes smaller: the peak pulse voltage generated by the power tube during the cut-off period is greater than the set value, which causes the power tube overvoltage protection circuit to operate frequently, which causes the power tube's conduction time to become shorter and the cut-off time to become longer.
2. If the voltage of 300V is lower than the normal value, the intensity of the magnetic field generated on the heating coil when the power tube is turned on becomes smaller.
3. The value of the power tube overvoltage protection circuit component changes to advance the overvoltage protection action.
4. Damage to the oscillating circuit components: the discharge time of the oscillating capacitor becomes longer, resulting in a smaller amplitude of the driving excitation square wave added to the driving circuit, resulting in a shorter turn-on time of the power tube.
5. The current detection circuit components are abnormal: the detection sampling voltage applied to the CPU by the current detection output is reduced, and the CPU detects that the voltage is less than the normal value, and mistakenly believes that the set power is small, so that the square wave pulse duty cycle Narrowed.
6. The component of the PWM pulse modulation circuit is abnormal, so that the control voltage of the CPU output added to the pulse width adjustment circuit is small.
7. The 18V output voltage is abnormal: the power tube is insufficiently excited, and the output power of the induction cooker is reduced. In this case, it is easy to cause excessive loss of the power tube and burn out.
