The invention discloses a constant-
power load control method and circuit applied to a DC-
DC converter, and the method comprises the steps: 1) respectively sampling an output
voltage and an inductive current through a
voltage sampling module and a current sampling module, and inputting the sampled
signal into an ADC module; 2) converting the input sampled
signal into a
digital signal through an ADCmodule, and inputting the
digital signal into a correction module; 3) comparing the
digital signal with a prediction value obtained by solving a prediction model by using a correction module, and employing the difference value as a correction
signal to be input into an MLD-MPC control module; and 4) solving the control model by using the MLD-MPC control module according to the correction signal,and achieving the
constant power load control of the DC-
DC converter according to the calculated switch duty ratio. According to the invention, the problems of steady-state error, poor dynamic performance and the like of a traditional
constant power control method are solved, so that the DC-
DC converter can quickly and stably adjust and maintain
constant power output when facing disturbance suchas input
voltage jump, load jump and the like.