Synchrophasor　estimation　was　mostly　used　in　transmission　systems　in　the　past,　and　it　is　difficult　to　directly　apply　an　existing　synchrophasor　algorithm　to　a　distribution　system　with　a　more　complex　structure　and　environment.　A　synchrophasor　estimation　algorithm　with　a　high　accuracy　and　fast　response　speed　is　required　to　complete　the　calculation　of　the　phasor　in　the　face　of　the　complex　and　changeable　power　signal　of　a　distribution　network.　Therefore,　an　enhanced　all-phase　discrete　Fourier　transform　(e-apDFT)　algorithm　is　proposed　for　a　distribution　system　in　this　paper,　and　the　algorithm　is　deployed　in　a　phasor　measurement　unit　(PMU)　prototype　based　on　digital　signal　processing　(DSP).　Aiming　to　solve　the　problem　of　the　accuracy　of　the　traditional　apDFT　being　reduced　when　the　response　speed　is　fast　due　to　the　influence　of　a　dense　spectrum,　the　existing　algorithm　is　improved　through　iteratively　compensating　the　spectral　interferences　to　the　main　bin　produced　by　adjacent　bins.　The　experimental　results　show　that　the　e-apDFT　algorithm　still　has　a　fast　response　speed　and　that　its　estimation　accuracy　is　much　better　than　that　of　the　traditional　apDFTs　in　the　presence　of　adjacent　harmonic　components.　The　proposed　algorithm　also　complies　with　the　IEEE　standards　for　P-class　PMUs.