The invention discloses a direct-current converter power master-slave control method. According to the control method, under the redesign of LCL parameters considering reactive compensation, the powermaster-slave control of a module parallel inverter is provided; a main control inverter adopts a double-ring structure of a direct-current side voltage outer ring and a bridge arm side current innerring of a module parallel inverter, and the active power obtained by a maintenance system from a new energy power generation unit is constant; a slave control inverter compensates the reactive power caused by excitation and leakage inductance of a system medium-frequency transformer according to the reference current of the main control inverter and based on that the voltage adopts a double-ring control structure of a power outer ring and a bridge arm side inductor current inner ring, the equal division of active power and the reactive power of the system are maintained, the parallel current-sharing of the direct-current converter modules is realized, and the system transmission efficiency is improved.