基于发射端信息的无线电能传输系统负载与互感辨识方法OA

In wireless power transfer systems,transmission efficiency and power capacity are primarily influenced by load and mutual inductance parameters.However,in practical applications,these parameters are often highly uncertain.For example,in the wireless charging system of electric vehicles,variations in vehicle chassis height and relative coil offsets alter the system's mutual inductance parameters.In addition,the equivalent battery load varies across vehicle models and changes dynamically during charging,directly affecting the system's transmission performance.Therefore,introducing parameter identification technology for real-time estimation of mutual inductance and load parameters not only enables accurate detection of system state but also supports optimization of control algorithms,thereby improving the overall performance of WPT systems. This paper takes a WPT system with the DLCC compensation topology as an example.A method for real-time joint identification of mutual inductance and load parameters is proposed by only collecting the voltage signals of the parallel compensation capacitor at the transmitting side.First,based on the system's steady-state equivalent-circuit model,multiple impedance expressions related to its transmission characteristics are derived,and a coupled-relationship equation system is established among the mutual inductance parameter,the load parameter,and the collected voltage information.By constructing auxiliary functions and introducing the intermediate variable γ,the original coupled equation is reconstructed and simplified,thereby decoupling the mutual inductance and load parameters.The originally complex joint-solution problem is transformed into a cubic equation.A unique real-number solution always exists under any practical operating condition,thereby verifying the theoretical effectiveness of the parameter identification method.By analyzing the relationship between the trigger signal phase and the required sampling information in inverter phase-shift control,it is possible to solve the cubic equation using only one voltage measurement.Then,a quantitative relationship expression between the sampled voltage and mutual inductance is derived to estimate the mutual inductance.Finally,a brief explanation of the overall identification process is given. A WPT system platform with a rated power of 1 kW is constructed.In the experiment,the fixed relationship between the capacitor-voltage phase and the trigger-signal phase across different phase-shift angles is verified by measuring the inverter trigger signal,inverter output-voltage waveform,and parallel-capacitor voltage waveform on the primary side.At the same time,tests under different load,mutual inductance,and phase-shift angle conditions show that the maximum identification errors of this method under variable inductance and variable load conditions are 5.3%and 6.9%,respectively.Compared with other methods,this method can maintain high identification accuracy without requiring communication between the primary and secondary sides,additional circuit topology,or uninterrupted power output.