Recovery algorithm for space charge waveform under temperature gradient in PEA method

This paper describes a new recovery algorithm for space charge measurement under temperature gradient using the pulsed electro-acoustic (PEA) method. As the temperature difference exists, the density of media becomes inhomogeneous and the waveforms gained by the PEA system are distorted seriously. In this study, the effect of temperature gradient on the acoustic propagation is discussed firstly, and an extended general solution for the acoustic propagation equation is gained. Then, the system transfer function is improved by adding the quadratic approximation to the general solution of the general wave propagation equation. With this new recovery algorithm, the distortion of the waveform can be successfully suppressed. In addition, the PEA waveform recovery method for coaxial cables under temperature gradient is also discussed.