Output Filter This paper presents a new electric power train for solar powered unmanned aerial vehicle (UAV). The proposed system structure is based on the development of the power supply system for both the So long and Zyphyr aircraft models. The proposed UAV model incorporates the Zyphry UAV use of an AC line feeder instead of DC power lines to power the propellers. The proposed power train includes solar panels, an energy management system based on lithium sulfide battery, inverter, AC bus-line and active output filter (AOF).
AOF topology is composed of a high switching frequency H-bridge inverter with a reduced size LC filter. The utilization of AOF system reduces the size and weight of the power transmission system and significantly improves its conversion efficiency by introducing an emulated series resistance with the H-bridge stage to ensure high quality pure sinusoidal waveform of the line voltage. This emulated series resistance produces an injected voltage across it to diminish unwanted harmonics created from the non-linear load.
A simulation model and experimental setup are created to simulate the proposed system and the system is tested under non-linear load condition with closed-loop feed-back control strategy. The obtained simulation and experimental results demonstrate that high-quality sinusoidal line voltage waveforms can be obtained using the active resistance compensation technique with total harmonic distortion factor less than 3%. Moreover, power losses analysis and conversion efficiency calculation of the proposed system are performed and compared with that of the conventional three-phase PWM inverter, which proved that the power losses are reduced by 31%.
- Active output filter
- Active resistance compensation
- Loss analysis
- Non-linear load
- Solar powered
- Unmanned aerial vehicle
Figure 1. Proposed Solar Powered Uav And Aof, (A) Single-Phase Square Wave Inverter With Ac-Bus Line And (B) Three-Phase Six-Step Inverter With Ac-Bus Line.
EXPECTED SIMULATION RESULTS:
Figure 2. Tested Insolation Conditions For Uav Pv Power System.
Figure 3. Pv Harvested Power.
Figure 4. Pv Voltage (Upper Trace) And Current (Low Trace).
Figure 5. Battery Power.
Figure 6. Non-Linear Load Output Dc Power.
Figure 7. Pv Harvested Power During Different Operating Modes.
A new electric power generation system for solar powered unmanned aerial vehicle (UAV) using active output filter has been proposed and investigated in this paper. The proposed power generation system is a potential progress of both the Solong and Zyphyr UAV models using the AC-bus line instead of the DC-bus line to power the propellers. It includes solar PV system, lithium-sulfur based power management system, inverter, AC bus-line. Balanced DC-link voltages of AOF have been accomplished using closed loop control of active resistance compensation.
which produces an injected voltage across it to diminish unwanted harmonics created from the non-linear load. The obtained simulation and experimental results and the voltage and current waveforms demonstrated the viability and the correctness of the proposed power generation system. The proposed active resistance compensation ensures a high-quality sinusoidal line voltage with total harmonic distortion less than 3%. Moreover
power loss analysis and conversion efficiency of the proposed system are performed and compared with that of the conventional three-phase PWM inverter. The obtained results proved that the power loss is reduced by 31%. More investigation of the proposed AOF for large-scale PV plants application with Battery energy management system integration using different wide band gab devices to optimize the system efficiency are required with applying different PWM techniques to utilize the passive elements sizing design which are the subject of future work.
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