Vibration　signals　of　distribution　switches　that　contain　mechanical　information　are　characterized　by　nonlinearity　and　nonstationarity.　Therefore,　based　on　the　singular　value　decomposition　of　time-frequency　matrix,　a　vibration　signal　feature　extraction　method　for　distribution　switches　was　proposed.　Hilbert-Huang　transform　(HHT)　band-pass　filter　was　used　to　construct　the　time-frequency　matrix　for　the　vibration　signal.　After　the　singular　value　decomposition　(SVD)　of　the　time-frequency　matrix,　the　characteristic　information　of　the　vibration　signal　would　be　decomposed　into　different　time-frequency　subspaces,　so　we　can　get　time-frequency　matrix　singular　values　as　the　feature　quantities,　the　feature　quantities　would　represent　the　mechanical　state　of　distribution　switches.　Fuzzy　c-mean　(FCM)　clustering　was　applied　to　these　time-frequency　matrix　singular　values　of　vibration　signals　which　was　monitored　in　normal　states　and　three　kinds　of　typical　malfunctions　including　relieved　insulated　pull　rod　of　phase　A　contacts,　mechanical　structure　clamping　stagnation　states　and　screw　loosing　states.　The　result　shows　that　the　feature　quantity　can　represent　the　mechanical　state　of　distribution　switches　accurately　and　effectively.　©2014　Chinese　Society　for　Electrical　Engineering