Sliding mode controller-based e-bike charging station for photovoltaic applications

Abstract

PV-based and wired type of the electrical bicycles (e-bike) battery charging stations widely is spreading because of the resonant network limitations and low efficiency of the wireless mode for these stations. The generated voltage of many of the PV panels such as JIYANGYIN HR-200 W-24 V at the maximum power point is around 36VDC. So, a step-down converter with a PID controller for Maximum Power Point Tracking (MPPT) of the PV panels is considered between PV panels and boost converter in order to decrease this voltage and enhance the current values for the load side. A sliding mode controller (SMC) equipped with a non-isolated DC-DC boost converter with reduced voltage stresses on the power switch is presented. The step-up converter increases the voltage to the utility level of the e-bike with around 360 Wh amount of energy. The main concerns about the converters are the efficiency, voltage, and current stresses, number of active or passive components in the converter topology and simplicity. In comparison with a conventional step-up converter, the selected converter has a lower dynamic loss in the input inductor that can give a proper efficiency by considering its higher voltage gain. The average state-space model for the SMC is used and the main advantage of the controller is its independency to the inductor current or the amount of the load. The proposed SMC is compared with PID and Fuzzy Logic Controller (FLC) methods and based on the results, the robustness, overshoot, and damping factor of the controller are at an acceptable and better level. All mathematical, simulation and comparison results are presented. A 720 Wh circuit has been implemented for charging all types of the Li-Ion or Li-Polymer batteries with 36VDC and 10 Ah specifications.