Wireless charging railway (WCR) systems have been recently introduced to solve the drawbacks of conventional electric locomotives such as noise, wear, arching, and sparking during wired power transfer. However, the high infrastructure cost of WCR systems weakens their competitiveness against conventional systems, thereby delaying commercialization. In this paper, a new concept of the WCR system that equips a ferriteless primary module is proposed to minimize the use of ferrite necessary for wireless charging and, therefore, to reduce the infrastructure cost. To effectively and efficiently investigate the feasibility of the proposed system with a high level of design complexity, a design optimization framework for high-power WCR systems is implemented to suppress the magnetic saturation and design abnormality during optimization. This framework successfully determines the optimal design that minimizes the mass of the secondary module with no use of the primary ferrite while satisfying various functional requirements of the WCR systems: electromagnetic field strength, magnetic saturation, and induced voltage. Compared with the ferrite-based WCR system, the proposed system can save up to 7.55 kg/m of primary ferrite, which is approximately $230.40/m for infrastructure costs. Thus, the feasibility of the proposed WCR system is proven through simulation-based design optimization, the results of which demonstrate the potential economic benefit for further commercialization.