The　instantaneous　output　power　of　a　dc　pulsed　power　supply　(DPPS)　pulsates,　resulting　in　the　generation　of　low-frequency　harmonic　current　(LFHC)　in　a　front-end　dc-dc　converter.　To　suppress　the　LFHC　and　improve　the　dynamic　performance　of　the　front-end　dc-dc　converter,　an　improved　active　disturbance　rejection　control　(ADRC)　is　proposed,　taking　into　account　the　closed-loop　output　impedance.　A　moving　average　filter　(MAF)　and　a　phase-leading　network　(PN)　are　embedded　in　the　forward　path　of　the　ADRC.　The　low　gain　characteristics　of　the　MAF　at　the　pulse　repetition　frequency　(f(pr))　and　its　integer　multiples　are　utilized　to　effectively　suppress　the　propagation　of　the　LFHC.　The　addition　of　a　PN　allows　the　voltage-loop　cutoff　frequency　to　exceed　f(pr),　thereby　significantly　improving　the　load　transient　response　of　the　system.　Furthermore,　a　closed-loop　parameter　design　method　based　on　frequency　response　analysis　is　introduced.　Finally,　an　800　W　(average)/2　kW　(peak)　DPPS　was　fabricated　and　tested,　and　the　experimental　results　verified　the　effectiveness　of　the　proposed　control　strategy.