Method for controlling fuzzy PID digital control DC-DC converter

Abstract

The invention discloses a method for controlling a fuzzy PID digital control DC-DC converter. Based on a control system which comprises an ADC unit, a comparator, a fuzzy PID compensator with a fuzzy control unit and a PID control unit, a digital pulse width modulator and a driver unit, the control system and the main topology of a Buck type DC-DC converter are connected in series to form a closed loop, the analog output voltage of the converter is subjected to A / D conversion and then is input to the comparator to be compared with a digital reference voltage signal, the output voltage error value and the error deviation value are calculated, the fuzzy control unit determines the duty ratio value of the switching period according to the output voltage error value and the error deviation value, and the digital pulse width modulator and the driver unit output corresponding PWM according to the duty ratio value to control a power tube to be connected or disconnected so that the output voltage value can be regulated. The defect of the nonlinear effect of the converter is overcome, the system response is accelerated, overshooting is reduced, and good input disturbance resistance and load disturbance resistance are achieved.

Description

technical field [0001] The invention relates to a digital switching converter, in particular to a fuzzy PID digital control DC-DC converter control method applied to a digital control switching converter, which can dynamically adjust conventional PID control parameters according to the output voltage error and error deviation, effectively Improve the transient response performance of the converter. Background technique [0002] DC-DC converters are widely used in various portable electronic products as DC voltage supply equipment. Early DC-DC converters usually use analog control because it has the advantages of simple control, high precision, and mature technology. The improvement of function and other requirements has promoted the generation and development of digital control power supply. Compared with analog control, digital control has many advantages, such as digital devices are not easily affected by aging and environmental variables, are not sensitive to noise, hav...

AI Technical Summary

Problems solved by technology

However, due to the nonlinear nature of the DC-DC converter system, the controller designed based on the small-signal model cannot guarantee the stability of the system under large-scale changes in input and load, so the scope of application of this model is greatly limited. , so the traditional control strategy is difficult to further improve the system performance

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