In this paper, a new class of wireless secondary converterless switched reluctance motor (WSC-SRM) drives is proposed and implemented. The key is to develop a unique wireless power transfer (WPT) system to directly drive the SRM without involving any power converter at the motor side. This is particularly essential to enable the WSC-SRM working in isolated environment with maintenance free. Based on selective WPT, the phase windings of the SRM can be properly energized by the same transmitter which adopts a newly developed compound structure. Meanwhile, signal duty ratio control of the transmitter is employed to achieve the speed control of the WSC-SRM. Both simulation and experimental results are given to validate the feasibility of the proposed system. For exemplification, a prototype is designed and constructed, which can provide WPT up to 150 mm transmission distance and achieve up to 72.8% transmission efficiency.

This paper proposes and implements the concept of flexible induction heating based on the magnetic resonant coupling (MRC) mechanism. In conventional induction heating systems, the variation of the relative position between the heater and workpiece significantly deteriorates the heating performance. In particular, the heating effect dramatically reduces with the increase of vertical displacement or horizontal misalignment. This paper utilizes the MRC mechanism to effectuate flexible induction heating; thus, handling the requirements of varying vertical displacement and horizontal misalignment for various cooking styles. Differing from a conventional induction heating, the proposed induction heating adopts one resonant coil in the heater and one resonant coil in the workpiece, which can significantly strengthen the coupling effect, and, hence, the heating effect. Both the simulation and experimental results are given to validate the feasibility and flexibility of the proposed induction heating.

This paper proposes and implements a novel quasi-omnidirectional dynamic wireless power transfer (WPT) system using double 3-D coils for drone applications. In the traditional omnidirectional WPT system, the receiver direction is always facing the 3-D transmitter center to maximally pick up the magnetic flux. However, the on-drone receiver normally proceeds horizontal or vertical movements so that it is unable to fully utilize the magnetic flux and result in serious magnetic flux leakage. Thus, by newly proposing the 3-D intermediate coil and artfully aligning specific quadrant of double 3-D coils to the center of the flying area, the proposed WPT system can flexibly and efficiently power the drone in the specific space. Moreover, only one single power source is needed to drive the transmitter coil without using the sophisticated current phase control. Therefore, the proposed system can simultaneously achieve both quasi-omnidirectional WPT and dynamic WPT for the drone so that its flying time can be significantly extended. The theoretical, simulated, and experimental results are given to validate the feasibility of the proposed WPT system.

In this paper, a novel kind of wireless motors, namely, the LCC-compensated wireless switched reluctance motor, is proposed and implemented. The definite advantages are that there is no power converter at the motor side and particularly no switched-capacitor array at the transmitter side to realize the multiple-frequency operation. The key is to develop an LCC compensation involving an inductor and two capacitors (the so-called LCC) for a multiple-frequency wireless power transfer system. As a result, only one transmitter is needed to targetedly feed three receivers, which directly energize the three phase windings of the motor. Particularly, there is no need to control switched capacitors to change the resonant frequency of the transmitter. Meanwhile, the burst firing control method is employed to realize the speed control. Both calculation and experimental results are presented to validate the feasibility of the proposed system. In the system prototype, the transmission distance can reach up to 150 mm and the transmission efficiency can be achieved up to 80%.

This paper proposes and implements a novel multi-frequency multi-power wireless power transfer (MFMP-WPT) system based on one single transmitter for simultaneously and compatibly energizing multi-standard receivers. Generally, implementing a multi-frequency WPT often requires a compromise in system complexity, control difficulty, switching frequency, or transmission efficiency. By using only a single transmitter with an artful inverter topology, the proposed MFMP-WPT system can effectively achieve multi-frequency multi-magnitude superposition and switching frequency reduction while maintaining the control fitness and convenience of square-wave generation with 50% duty cycle. Moreover, by switching at the fundamental frequency in a range of 80-130 kHz, the single transmitter becomes competent for one-to-many MFMP-WPT operation for diverse wireless power on-demands. Consequently, the fundamental and high-order harmonic wireless energies with multiple power levels can be, respectively, picked up by the multi-standard receivers, depending on their energy requirements. The experimental transmission and system efficiencies can reach 81.57% and 64.74% under MFMP-WPT, respectively. Theoretical analysis, computer simulation, and experimental results are provided to verify the feasibility of the proposed MFMP-WPT system.