Description:
This article presents a wireless power transfer system for substation inspection robots. Employing a dual-coupled double inductor-capacitor-capacitor (LCC-LCC) compensation topology, the system aims to address the prevalent challenge of misalignment tolerance improvements. It reveals that the system's output is predominantly influenced by the denominator parameter (i.e.,
Description:
This article proposes a novel extended sliding-mode predictive control strategy for three-phase three-level voltage source inverters. Initially, the control domain is established using sliding-mode theory, dynamically reducing the search space. Subsequently, a unique parallel optimization strategy is presented in the two-phase stationary coordinate system, with an analysis of the monotonicity of the cost functions and the constraints within the search space. Compared to traditional model predictive control, this approach results in a calculation time reduction of at least 51.3%. To mitigate output ripple, a novel design method for virtual voltage vectors (VVVs) is proposed based on
Description:
Free-standing magnetic field energy harvesters (FSMFEHs) have promising potential in charging sensors used in electrical power grids. The output power of the FSMFEH is highly dependent on the load resistance. However, the load resistance of the sensors varies over a wide range during the operation process. Therefore, a crucial challenge for an FSMFEH system is to maintain high output power over a wide load range. In this letter, an innovative reconfigurable rectifier-based FSMFEH system with two coils connected in parallel is proposed. First, a new structure of two identical coils in parallel is proposed in magnetic energy harvesting applications. Then, a reconfigurable rectifier with two operation modes is developed to incorporate the new coil structure. By switching between the full-bridge mode and the half-bridge mode according to the actual load demand, the proposed FSMFEH can maintain high output power over a wide load range. In addition, the mode transition can be easily achieved by shorting one of the diodes, leading to a simple and low-loss control. The effectiveness of the proposed FSMFEH system is verified based on a laboratory prototype. It is provided that the experimental result is consistent with the theoretical analysis. The output power can be maintained above 8.19 mW within the 50-1500
Description:
This paper proposes a new method for simultaneous dynamic wireless power and data transfer (SDWPDT). When the receiver is moving, both power and data transfer channels are dynamically switched ON/OFF according to the receiver's position. In essence, data is transmitted through the high-frequency electric field (EF) generated by the parasitic capacitances of the coupling coils and the metal shield plates, while power is transmitted through the relatively low-frequency magnetic field (MF) generated by coupling coils. By doing this, mutual interference between two transfer channels (i.e., power and data transfer channels) is relatively small. Firstly, the interference from power to data can be greatly reduced due to the absence of a direct electrical wire-based connection. Secondly, the power loss caused by the data transfer channel in the power link is very small so it can be ignored. In addition, the implementation of real-time communication facilitates the establishment of a closed-loop control within the system. This mechanism guarantees consistent power output during dynamic movement, even in the presence of fluctuations in load or input voltage. Laboratory prototype-based experimental findings substantiate the feasibility of the proposed approach.