Method and device for hiccup control of LLC resonant circuit

Abstract

The invention discloses a hiccup control method and device of an LLC resonant circuit. The method comprises the following steps: acquiring an actual output value of the LLC resonant circuit; obtaining hiccup duration corresponding to a difference value between the set output value and the actual output value; controlling a drive circuit of the LLC resonant circuit to be in an open state, and detecting whether the duration of the open state of the drive circuit is greater than or equal to the hiccup duration; and when the duration is greater than or equal to the hiccup duration, controlling the driving circuit to be in a closed state. According to the invention, the hiccup duration corresponding to the difference value between the set output value and the actual output value is obtained, and the drive circuit is controlled to be in the open state or the closed state according to the hiccup duration, so that the actual output value is maintained near the set output value; and the drive is prevented from being always kept in the open state when the actual output value is greater than the set output value, the control precision of hiccup control is improved, and the LLC hiccup control effect can be improved without additionally adding a hardware circuit.

Description

technical field [0001] The invention relates to the technical field of LLC resonant circuits, in particular to a hiccup control method and device for LLC resonant circuits. Background technique [0002] LLC (Lr, Lm, Cr, resonant inductance, excitation inductance, resonant capacitor) hiccups, also known as intermittent work. LLC generally controls the output voltage or output current through frequency modulation. Although the frequency modulation range is very wide, when the frequency is adjusted to the maximum at light load or no load, it will still exceed the set voltage or current value. Intermittent working mode is required to control the output voltage or output current within the set value. [0003] When hiccup control is realized by software, the drive is always kept on when the actual value is less than the set value, and the drive is always kept off when the actual value is greater than the set value, but this method requires sampling It is very high, and the requi...

AI Technical Summary

Problems solved by technology

[0003] When hiccup control is realized by software, it is often to keep the drive on when the actual value is less than the set value, and to keep the drive off when the actual value is greater than the set value, but this method requires sampling Very high, and the requirements for the control period are also very high. If the sampling is disturbed or the control period is too long, the actual value will overshoot and the control accuracy will be poor.

However, when the hiccup control is realized by hardware, an additional hardware circuit is required, resulting in high hardware cost

Therefore, the current hiccup control schemes are less effective

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