Optimization of the Magnetic Field Computation in Wireless Power Transfer System by Two-Dimensional Feature Selective Validation and Maximum Value Filtered Method

Magnetic field (MF) analysis in wireless power transfer systems (WPTSs) is one of the key problems. This paper proposes an optimization algorithm to determine the MF by calculating the simplified Biot-Savart integral. The number of intervals (NOIs) in the integral is the key to the accuracy and efficiency of the algorithm. The maximum of the MF changes sharply with NOI, leading to a bad optimal NOI. To solve this problem, two methods are used. First, according to the positions of the maximum, the relatively high value, and the idea of noise-point-elimination in digital image processing, the maximum value filtered method (MVFM) is proposed. The second method is the two-dimensional (2-D) feature selective validation (FSV). By combining the MVFM and the 2D-FSV, on an NOI step equaling to 10, the optimal NOI is decreased from 350 to 90, which significantly meets the balance of the accuracy and efficiency. Furthermore, for a variable NOI step situation, local and global optimal NOIs have been analyzed. MVFM is not only suitable for the MF calculation in WPTSs but also for when the maximum value needs to be addressed. 2D-FSV also expands the application from the final result evaluation to the evaluation in an algorithm.