Model-Free Sliding-Mode Voltage-Current Dual-Loop Control for LCL Inverter

In renewable power generation systems,
$LCL$
filters are widely used in inverter filtering due to the small size and excellent filtering performance. However, there are complex coupling effects between the dq-axis in
$LCL$
inverter control, and the conventional PI control based on feedforward decoupling (PIFFD) requires accurate filter parameters. To reduce the dependence of
$LCL$
inverter voltage-current dual-loop control on filter parameters, a multiple-input and multiple-output (MIMO) model free sliding mode controller (MFSMC) is proposed. A pseudo-Jacobi matrix (PJM) is introduced to address the coupling interaction of voltage and current under the
$dq$
frame, and the sliding mode control (SMC) method is employed to enhance the robustness of the controller under parameter variation conditions. Finally, the proposed MFSMC is contrasted with the PIFFD under filter parameters mismatch and load power variation scenarios, and proves that the MFSMC has better THD of voltage current and faster response time.