With the growing penetration of electric vehicles (EVs) in the market, multifunctional charging systems are required that are able to integrate renewable energy sources and operate under various charging and driving conditions without any disturbances. This paper proposes a multifunctional isolated High Gain converter (HGC) with a novel sliding mode reaching law (NSMRL) assisted control strategy for solar PV (SPV) and grid integrated EV charging applications. Proposed Architecture for Grid/ PV/ regenerative brake/ hybrid PV-grid charging and propulsion with a single power conversion stage. NSMRL-assisted control contributes to better DC-link voltage regulation, transient response, and strong operation under renewable intermittency and load variations. In MATLAB/Simulink, performance is verified for all operating modes. The simulation results show that bidirectional power flow, smooth mode switching, and energy management are achieved. The results indicate that the proposed approach can significantly improve the power quality and the performance of the converter as the THD of the grid voltage is reduced from 2.54% to 0.73% under steady state operation and 0.79% under plug-in charging.