Large-current power supply and constant-current control method and system thereof

A constant-current control method for a large-current power supply which comprises:

• obtaining a unit step response coefficient dataset of an output current from a pulse-width modulation (PWM) controller to the power supply, wherein the PWM controller is configured to control a working state of a switch tube for a Buck circuit;
• determining a dynamic matrix according to the unit step response coefficient dataset, wherein an element in the dynamic matrix is a unit step response coefficient in the unit step response coefficient dataset;
• determining a predictive control model of the power supply according to the dynamic matrix, a control increment sequence, and an output current of the power supply under the action of a current control quantity;
• and
• controlling the working state of the switch tube for the Buck circuit in the power supply according to an output current predicted by the predictive control model, so that the output current of the power supply is maintained at an expected value.

A constant-current control system for a large-current power supply, which comprises:

• a dataset obtaining module, configured to obtain a unit step response coefficient dataset of an output current from a pulse-width modulation (PWM) controller to the power supply, wherein the PWM controller is configured to control a working state of a switch tube for a Buck circuit;
• a dynamic matrix determination module, configured to determine a dynamic matrix according to the unit step response coefficient dataset, wherein an element in the dynamic matrix is a unit step response coefficient in the unit step response coefficient dataset;
• a predictive model determination module, configured to determine a predictive control model of the power supply according to the dynamic matrix, a control increment sequence, and an output current of the power supply under the action of a current control quantity;
• and
• a control module, configured to control the working state of the switch tube for the Buck circuit in the power supply according to an output current predicted by the predictive control model, so that the output current of the power supply is maintained at an expected value.