Co-simulation Of Piezoelectric Energy Harvester With External Circuits Based On The Reduced Order Method

In recent years,with the large number of fossil energy sources being used,its reserves are decreasing rapidly.It is urgent to develop new energy sources.In the field of civil engineering,the use of power energy harvester(PEH)to capture the vibration of traffic environment can be used to power the wireless sensor equipment so as to better realize the structure monitoring.This is a hot topic at present.But how to quickly and accurately calculate the capture output of PEH under complex loads is the most critical part.The current main programs and algorithms are still unable to achieve complete PEH-CIRCUIT coupling simulation of complex loads.Therefore,it is necessary to devote the coupled simulation under complex loads rapidly.Based on the finite element method and the model order reduction technique,a new system level simulation method considering the bidirectional coupling effect of the PEH and the cooperative analysis of the external circuit are proposed in this paper.The specific work is as follows:Firstly,we build a piezoelectric cantilever beam relied on COMSOL,and use the built-in command to extract the system matrix,including the stiffness matrix,mass matrix and damping matrix.After applying the boundary conditions,The dynamic control equation of the PEH is established.Secondly,Krylov subspace model order reduction and Eigenvector-based model order reduction are used to reduce the order of the dynamic control equation to obtain the reduced order model.At the same time,these two ways can keep the key dynamic characteristics of the system,and greatly improve the operation efficiency.Besides,we use single restistance circuits and the standard circuits to co-simulite the reduced order model based on the SIMULINK environment.From the test and harmonic response,we can validate the accuracy of the present model.Moreover,the parameters used in the equivalent circuit model can be conveniently got by eigenvector-based model order reduction.Here,P-SSHI circuit and S-SSHI circuit have been presented to validate the latter method.Finally,we test the vertical acceleration when trains passing the bridge to obatain the output voltage based on Krylov subspace-based model order reduction.The system level simulation model proposed in this paper is suitable for any complex geometry PEH devices,which is not only suitable for cantilevered beam,but also suitable for complex models.The system level simulation analysis method can be connected with any complex circuit,because the simulation model only considering the input of loads and the output of electrical term.It is more convenient for the design of external circuits.Besides,external excitation can be more complex.The above three functions greatly improve the scope of application of the analytical method.