Optimal energy management strategy for distributed solar-powered UAV with multiple propellers

Drawing upon the current advances in energy management and power control strategies for solar drones, this paper first examines the comprehensive design criteria for high altitude long-endurance models. It investigates the energy balance dynamics and the configuration of power supply systems in these drones, proposing a joint solution that couples photovoltaic panels with lithium-sulphur batteries for the power supply system. Moreover, the voltage level and topological structure of the power supply system were determined in conjunction with the mission payload requirements of the solar-powered UAVs. Based on this foundation, an in-depth exploration of the energy management strategy for the power supply system is undertaken, culminating in a hierarchical control architecture-based solution. State machine control and droop control are adopted as the superordinate control measures, partitioning the system's operational modes and governing power allocation onboard. The inferior control strategies encompass maximum power control, constrained power control, and lithium-sulphur battery charging/discharging controls reliant on bus voltage, which collectively manage the circuit's output status and power flow. Following this topic, the developed control methodologies are modeled and simulated in Matlab/Simulink, ultimately ensuring stable DC bus voltage, balanced energy supply and consumption.