Application of double integral sliding mode-controlled KY converter for efficient solar EV charging

Solar-Powered Electric Vehicle (EV) charging systems are emerging as an efficient alternative to grid-dependent infrastructure. However, partial shading conditions (PSC) and converter-induced ripple significantly reduce the panel efficiency, resulting in longer charging time. Conventional maximum power point tracking (MPPT) techniques such as perturb and observe (P&O) and incremental conductance (InC) exhibit slow convergence and oscillation around MPP under PSC. Although numerous metaheuristic and hybrid MPPT strategies have been reported, they often suffer from high computational complexity, slower convergence rates, require large datasets, demand high processing power and limited real-time feasibility. Additionally, conventional boost converters suffer from high output ripple and limited voltage stability, making them unsuitable for high-power EV charging. To overcome these challenges, this study proposes a double integral sliding mode control (DISMC)-based KY converter integrated with the InC MPPT algorithm to enhance tracking accuracy, voltage stability and power conversion efficiency. A Lyapunov-based control law is developed for DISMC using the PV voltage and inductor current as state variables to ensure stable converter operation. Simulation studies on a 400 W PV system demonstrate improved and faster GMPP tracking, reduced oscillations around MPP, minimised chattering, higher power conversion efficiency and lower steady-state error, compared to conventional control methods. When applied to a 25-kW solar EV charging application, the simulation shows increased charging current, state-of-charge rate and power conversion efficiency, thereby reducing the battery charging time.Experimental validation using a 40 W prototype, confirms the robustness and scalability of the proposed DISMC–KY converter under practical operating conditions.