Abstract The emerging number of nonlinear loads has given elevated interest in developing shunt active power filters (SHAPF) to eliminate the grid issues resulting from the current distortions. This paper proposes an improved photovoltaic (PV) module integrated dual boost high step-up three-port isolated direct current (dc)-dc converter to deliver high output voltage for the low-voltage input. A three-phase three-level (3P3L) T-type inverter is operated as a SHAPF to eliminate the current harmonics. The T-type 3P3L multilevel inverter (MLI) incorporated with the proposed system reduces the number of switches and gate driver circuits compared with widely used MLI. The proposed system generates the compensation current to eliminate the current harmonics in the three-phase distribution network by means of the SHAPF dc-link voltage control. A dc-space vector control scheme is incorporated to generate the firing pulses for the MLI. A comparative evaluation of the latest MLIs reveals that the proposed topology requires a lower quantity of dc sources and power semiconductor switches. In order to validate the operation of the proposed topology, the simulation and experimental consequences of a 3P3L PV-integrated dual boost three-port (DBTP) dc-dc converter–fed T-type MLI-based SHAPF controlled by the DBTP dc-dc converter are presented.