CONTROL METHOD CAPABLE OF IMPROVING HEAVY-TO-LIGHT LOAD DYNAMIC RESPONSE OF SWITCH-MODE POWER SUPPLY

摘要

A control method capable of improving heavy-to-light load dynamic response of a switch-mode power supply, which is based on a control system comprising a sampling module, a dynamic control module, an error calculation module, a PID module, a mode control module, and a PWM module. The control system is connected to the controlled switch-mode power supply to form a close loop. When an output voltage of the switch-mode power supply exceeds its set maximum voltage, the output is rapidly stabilized by means of a low-power heavy-to-light load mode, the change in the output voltage is monitored in the heavy-to-light load mode so as to calculate the next switch cycle, and the load magnitude is obtained according to the switch cycle. After exiting the dynamic mode, the working state is switched to that corresponding to the load point, and after the switch, the power and steady-state load consumption are not much different, so that subsequent voltage oscillations is eliminated, and the dynamic recovery duration is shortened.