The　three-phase　four-wire　shunt　active　power　filter　(APF)　is　an　effective　method　to　solve　the　harmonic　problem　in　three-phase　four-wire　power　systems.　In　addition,　it　has　two　possible　topologies,　a　four-leg　inverter　and　a　three-leg　inverter　with　a　split-capacitor.　There　are　some　studies　investigating　DC-link　voltage　control　in　three-phase　four-wire　APFs.　However,　when　compared　to　the　four-leg　inverter　topology,　maintaining　the　balance　between　the　DC-link　upper　and　lower　capacitor　voltages　becomes　a　unique　problem　in　the　three-leg　inverter　with　a　split-capacitor　topology,　and　previous　studies　seldom　pay　attention　to　this　fact.　In　this　paper,　the　influence　of　the　balance　between　the　two　DC-link　voltages　on　the　compensation　performance,　and　the　influence　of　the　voltage　balance　controller　on　the　compensation　performance,　are　analyzed.　To　achieve　the　balance　between　the　two　DC-link　capacitor　voltages,　and　to　avoid　the　adverse　effect　the　voltage　balance　controller　has　on　the　APF　compensation　performance,　a　new　DC-link　voltage　balance　control　strategy　for　the　three-phase　four-wire　split-capacitor　APF　is　proposed.　Representative　simulation　and　experimental　results　are　presented　to　verify　the　analysis　and　the　proposed　DC-link　voltage　balance　control　strategy.　©　2016　KIPE.