The invention discloses a
voltage-sharing
control circuit and a control method thereof. The
control circuit comprises three main
power circuits connected in series, a sampling circuit and a main control
chip, the output ends of the three main
power circuits are connected with the input end of the sampling circuit, and the output end of the sampling circuit is connected with the main control
chip;the main control
chip is connected with the control ends of the three main
power circuits respectively, each main power circuit comprises a full-bridge conversion module, a
resonance module, a rectification module and a filtering module, and the full-bridge conversion module, the
resonance module, the rectification module and the filtering module are connected in sequence; when a direct-current power supply outputs in a light-load or no-load mode, the three main power circuits carry out PWM control in a copy wave sending mode, meanwhile, the output
voltage-sharing rings of the two main power circuits work to carry out drive
signal duty ratio fine adjustment, and
voltage-sharing control is achieved. The circuit provided by the invention has the
advantage of solving the problem that the voltage of the direct-current power supply cannot be equalized during no-load or light-load output.