Research On Integrated Platform Of Inductive Heating And Wireless Power Transfer

Wireless kitchen appliances using Wireless Power Transfer(WPT)technology have received more and more attention because of their advantages such as high safety,easy cleaning and strong operability.Inductive Heating(IH)technology is more and more widely used in kitchen appliances due to its safety,high efficiency and environmental protection.Because the integrated platform integrates Inductive Heating technology and Wireless Power Transfer technology on the same transmitting platform,the paper analyzes the equivalent circuits of the two operating modes,which are the loosely coupled transformer and the equivalent mapped resistance.The equivalent circuits provide the basis for circuit analysis.Then based on the Finite Element Analysis(FEA)tool,the eddy current power,coil inductance and other physical quantities are analyzed from the aspects of magnetic stripe number,axial distance,offset distance,working frequency and pot conductivity,etc.This analysis provides an optimization method for the design of the transmitting coil.The paper has made a systematic elaboration on the heating principle of traditional Inductive Heating cookers.Since the main circuit topology of traditional Inductive Heating cookers is not suitable for integrated platforms,the paper applies Ttype network,which has excellent electrical characteristics,to integrated platforms.In view of the characteristics of the inductance of the integrated platform under different operating modes,this paper proposes a T-type network optimization design method,which switches compensating topology with relay.This method ensures the transmission efficiency and power factor of the integrated platform under the two operating modes.Finally,the high-frequency effect of the transmitting topology is analyzed.This topology has a high impedance and a strong suppression effect to highorder harmonics,which ensures the accuracy of the fundamental-wave analysis method.Considering the application background of the integrated platform,the paper compares the advantages and disadvantages of the DC side power adjustment and the AC side power adjustment method,and determines the system power adjustment scheme.The power loss under no-load state of the system is analyzed to ensure the safety under no-load state.Then,the power-limiting measures of the system during the load switching process are designed.The bus current collection method has an obvious shortcoming that its calculation of the output power is inaccurate.In view of this shortcoming,a method for obtaining the output power by collecting voltage of compensating capacitor is proposed,which ensures the safety of system while switching operating mode.That is,it will not cause danger to electrical equipment later.Finally,an improvement of the proposed method under phase shift control is proposed,and the influence of parasitic resistance in capacitor is analyzed.Which improved the accuracy of calculation and control.Finally,based on the theoretical analysis results,an integrated platform experimental prototype was built,which realized the combination of Inductive Heating function and Wireless Power Transfer function.The wireless transmitting power is close to 300 W and the transmitting distance reaches 70 mm.And the Inductive Heating power exceeds 600 W and the heating distance reaches 10 mm.