Two-step topology optimization using topology constraint for improving the diversity of solution

The topology optimizations which optimize a material arrangement on an element, without extracting feature quantity, are attractive methods, because we can obtain a free idea of the initial design of magnetic devices. However, in actual design processes, all of the required features of the products cannot be included objective functions, such as ease of manufacture or influence of rise in heat. Moreover, the multiple-purpose optimizations concerning many kinds of physical phenomena have difficulty with calculation time. Thus, it is necessary to estimate whether the obtained optimal solution under the limited condition is applicable to an actual designing of magnetic devices. This paper introduces two-step topology optimization method using the constraints on the similarity of the topology, which provides us various topologies including suboptimal solutions. By using the proposed method, we can determine some actual applicable solutions out of obtained solutions. The proposed method was verified by applying it to the C-core problem and the magnetic shield problem, which demonstrated the effectiveness of the proposed method.