Abstract: This paper firstly proposes an intermediate frequency isolated photovoltaic ±35 kV/500 kW DC converter. The DC converter consists of a three-phase T-type three-level intermediate frequency parallel inverter module,an intermediate frequency 400 Hz 24-pulse phase-shift boosting transformer,a three-phase diode rectifier bridge and a high-voltage filter circuit. The converter has the advantages of high boost ratio,simple structure and low costs. Secondly,in order to realize the real-time equalization of the active and reactive power of the parallel module of the inverter,a master-slave power control scheme of instantaneous power equalization is adopted in this paper. Then,an improved LCL filter parameter design method based on reactive power compensation of intermediate frequency transformer is proposed to improve the efficiency of the system. Finally,through Matlab/Simulink simulation and the photovoltaic power generation medium-voltage DC collection field demonstration project built by Zhang Bei National Research and Development（Experiment）Center of Large Wind Power Grid Connected System,the control method and design concept of the proposed DC converter are verified. The maximum efficiency is 96.33% and the boost ratio is as high as 88. The output voltage is ±35 kV. Simulation and experimental results prove the feasibility of the proposed DC converter.