Electromagnetic analysis of energy system devices

by Li, Yan

Many new applications of energy system devices have been developed to save energy, improve the controllability and stability of industrial processes, and reduce the weight, volume and cost of consumer devices. Due to the novelty of these devices, traditional empirical methods and lumped-parameter circuit theory methods are not sufficient for product development and optimization. Electromagnetic analysis approaches can provide accurate parameter calculation and performance prediction for these new products / prototypes of energy system devices. They are powerful and efficient tools for new product development and existing product optimization.

The research analysis work of this thesis applied the LTA (Layer Theory Approach) and FEM (Finite Element Method) to analyze two types of new energy system devices, a permanent magnet coupling and its derivatives and the prototype of a linear reluctance machine, respectively. LTA is a suitable and efficient tool for devices like linear induction machines and permanent magnet couplings, which include sheet conductors as secondaries. FEM is an analysis tool with wider application area. It is applicable for most devices even with complicated structures. But, it has numerous disadvantages including large memory requirements and very long computational times. The performance of a permanent magnet dynamometer-brake coupling was predicted with the LTA program and compared with experimental results. The comparison shows good correlation between the layer model and the test data. The LTA program was also proved to be a useful tool for parametric design studies and conceptual designs for devices such as large quiet brakes to be used in the testing of drives for Navy ships. 2-D FEM with calibration techniques were adopted to analyze the complicated prototype of a linear reluctance machine. The analysis results successfully helped confirm the operation of the prototype device and investigate its uncompromised performance. In addition, it provides useful information for next generation product development.