| The research on wireless charging is paid more and more attention in recent years. Since the MIT research team lights a 60-watt bulb in two meters, the wireless power transmission technology is developed by leaps and bounds. Some wireless power transmission products have been emerged in the market, such as mobile phones, mp3, laptop chargers, and so on. Although these products can transfer power wirelessly, the receivers are nearly zero distance to the transmitter. Furthermore, the research on wireless power transmission today mostly fixed at a single transmitter to a single receiver model. The demand of a single transmitter to multiple receivers’ mode becomes growing because of the increase of electronic products.In this paper, parameter design and frequency control of dual-load magnetic coupled resonant wireless power transmission have been studied, and the transmitter can power two receivers stably and efficiently at a certain distance. The main contents are as follows:1. The impact of angle between the transmitting and receiving coils on the transmission performance for the dual-load wireless power transmission. The basic principle of dual-load wireless power transfer via magnetic resonance is studied, and the circuit model which considers the mutual inductance between the two receiving coils is analyzed. The main factors that affect the system efficiency and power are also discussed. The studies show that the right angles between the transmitting and receiving coils will enhance the mutual inductance, which making a better transmission performance of the system.2. Study on the system structure of dual-load wireless power transmission based on the law of energy flow. The system energy flow rule, in which the reflected energy absorbed by the resistor is the source energy of the two receiving ends, is deduced by using the circuit principle and introducing the reflected impedance. According to this energy flow law, the different loads of the receivers are discussed and the structure of the system is determined finally.3. Propose an improved artificial bee colony algorithm. Artificial bee colony algorithm has a strong ability of exploration, but its local mining ability is weak. The adaptive neighborhood search is achieved in onlooker phase by using sine function and it can accelerate the convergence speed of the algorithm. In addition, the Tent sequence with perturbation is applied to improve the global optimization ability because it prevents prematurity and avoids the local optimal.4. System parameter design based on improved artificial bee colony algorithm. The parameters of the system are too difficult to determine because the modules of wireless power transmission have strong coupling. In order to maximize the efficiency as far as possible, the non-linear programming model of the system is set up firstly. Then the improved artificial bee colony algorithm is used to look for the best parameters under some transmission distance and the power of the receivers are satisfied meanwhile.5. Control the system frequency based on the variable universe fuzzy controller and capacitor array. By studying the impact of frequency shift of the sending and receiving ends, the stability of transmitter frequency is the key to keeping transfer efficiency highly. A control method of transmitter frequency is proposed in which the variable universe fuzzy controller is used. Variable universe fuzzy controller can control the transmitter frequency accurately because it has adaptive interval domain. The capacitor array is further designed by nonlinear cascade linear array. To maintain a constant frequency, the nonlinear capacitor array is used to tune coarsely, and the linear capacitor array is employed to tune carefully. Experiments show that this method can optimize the performance of the system because it not only makes the oscillation smaller, but also reduces the closed number of switches and expands the scope of frequency control. |
PDF Full Text Request