The　new-type　distribution　network　with　a　high　penetration　of　distributed　generation　(DG)　faces　challenges　such　as　significant　power　fluctuations　and　the　inability　to　fully　compensate　for　single-phase　grounding　fault　currents.　The　active　compensator,　utilizing　power　electronic　conversion　technology,　can　simultaneously　achieve　power　compensation　and　full　compensation　of　grounding　fault　currents.　However,　its　compensation　performance　is　affected　by　three-phase　asymmetrical　voltage,　and　the　cost　of　active　compensators　is　relatively　high.　Therefore,　this　paper　proposes　a　fault　suppression　strategy　that　considers　the　impact　of　asymmetrical　voltage　and　is　suitable　for　active　compensators.　Firstly,　a　star-connected　three-phase　four-leg　cascaded　H-bridge　active　compensator　topology　is　proposed　to　achieve　active　compensation,　grounding　fault　suppression,　and　asymmetrical　voltage　mitigation　while　reducing　costs.　Meanwhile,　the　impact　of　three-phase　asymmetrical　voltage　on　the　performance　of　active　compensation　is　analysed.　And　a　voltage-current　composite　control-based　asymmetrical　voltage　suppression　strategy　is　proposed.　This　strategy　enables　seamless　switching　between　asymmetrical　voltage　suppression　and　grounding　fault　current　compensation　without　transient　impact.　Finally,　physical　experiments　verify　the　effectiveness　of　the　proposed　topology　and　fault　suppression　strategy,　demonstrating　excellent　compensation　performance　and　economic　feasibility.　©　2025　The　Authors