Marine-controlled　source　electromagnetic　transmitter　is　an　important　equipment　for　the　investigation　of　marine　geology　and　exploration　of　oil,　gas,　and　mineral　resources　in　recent　years.　There　are　some　problems　from　the　direct　current-direct　current　(DC-DC)　converter　of　high　power　marine　transmitter,　the　load　is　light,　when　the　output　current　is　relatively　small,　the　lagging-leg　switching　cannot　easily　achieve　the　zero　voltage　switching　(ZVS),　and　the　conversion　efficiency　of　the　heat　converter　requires　improvement.　This　paper　proposes　a　small　power　ZVS　circuits　for　the　marine-controlled　source　electromagnetic　transmitter　(SPZVSC-MCSET).　The　resonant　inductance　and　blocking　capacitor　are　appropriately　used　in　the　current-doubler-rectifier　converter,　when　in　a　wide　load　range　the　current-doubler-rectifier　converter　can　achieve　ZVS.　The　Saber　simulation　and　100　W　electromagnetic　transmitter　are　used　to　verify　the　results.　©　2019　Institution　of　Engineering　and　Technology.　All　rights　reserved.