Design method of digital power supply loop compensator based on PIDalpha

Abstract

The invention relates to a design method of a digital power supply loop compensator based on PIDalpha, thereby controlling the output voltage of a digital power supply stably, accurately and quickly.The method comprises the following steps: (1), drawing a digital power supply main power transfer function Bode diagram based on simulation software; (2), designing an analog two-zero-point two-pole compensator with the same zero and pole types as the PIDalpha digital loop compensator, and drawing a compensator Bode diagram; (3), converting the analog two-zero-point two-pole compensator in an s domain into a PID alpha digital loop compensator in a z domain; (4), carrying out programming based on structural characteristics of a PIDalpha digital loop compensator algorithm to realize functions; and (5), debugging the functions of the PIDalpha digital power supply loop compensator by a prototype experiment. According to the design method provided by the invention, a loop compensator with excellent performance can be designed for the digital power supply to realize stable, accurate, rapid controlling of the output voltage of the digital power supply.

Description

Technical field [0001] The invention relates to the technical field of digital power supply control, in particular to a design method of a digital power loop compensator based on PIDα. Background technique [0002] The accuracy and stability of the output voltage of the digital power supply, as well as the fast response to the input voltage and load current disturbances are all determined by the open-loop gain phase curve (ie Bode diagram) of the digital power system. The stability criterion of the feedback system is: at the frequency where the open-loop loop gain is 1 (that is, the crossover frequency fc), the open-loop phase delay must be less than 360°. Since the negative feedback comes with a phase delay of -180°, the difference between the phase angle at the crossover frequency fc and -180° is defined as the phase margin. If the phase margin is too small, the DC / DC converter will experience self-oscillation. Engineering experience often design the phase margin above 60°. ...

AI Technical Summary

Problems solved by technology

[0006] The design method of a digital power supply loop compensator based on PIDα proposed by the present invention can solve the inability to control the strong coupling relationship between the control coefficient of the PIDα loop compensator and the key coefficient in the open-loop transfer function of the digital power supply. The technical problem of independent adjustment of the stability, accuracy and rapidity of the loop

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