Nuclear fusion energy is a sustainable and clean energy alternative and is regarded as one of the best choices to address the global energy crisis and climate change issues. Magnet power supplies are important components in fusion reactors and need to balance dynamic rapidity and stability. Based on the operating parameters of nuclear fusion magnets, this paper proposes a DC power supply topology for fusion magnets and studies its load characteristics through MATLAB/Simulink. Simulation results show that the system has the ability of operating in four quadrants, can maintain stability under different load working conditions, and respond quickly according to the action signals, verifying the feasibility of this topology. Under the condition that the control strategy is proposed, the adjustment duration of the system is approximately linearly related to the inductance of the magnet.