Comparison of different controllers for wireless charging system in AUVs

One of the applications of Wireless Power Transfer (WPT) is its use in Autonomous Underwater Vehicles (AUVs), which has become very popular in recent years. Underwater charging an AUV has several challenges. One of these challenges is the existence of water turbulence that causes the AUV to move and the magnetic coupling between the transmitter and receiver coils to change. Changes in the coupling coefficient also cause the output voltage to change. Using the right controller in AUVs is very important to keep the output voltage constant at a certain value. In this paper, by considering the characteristics of a magnetic coupler and using an LCC-LCC converter to compensate for the WPT system, three methods for controlling the output voltage are presented and their performance for the proposed WPT system is evaluated and compared. These three methods include using a buck-boost converter at the beginning of the circuit, using the PWM method to generate gate signals of the input inverter, and using the Z-Source converter. The results show that using a buck-boost converter at the beginning of the circuit performs better than the other two methods. To confirm the above, the simulation results of the proposed WPT system are presented along with three control methods.