energies Article Boundary Identification for Traction Energy Conservation Capability of Urban Rail Timetables: A Case Study of the Beijing Batong Line Jiang Liu 1,*, Tian-tian Li 2, Bai-gen Cai 3 and Jiao Zhang 4 1 School of Electronic and Information Engineering, Beijing Jiaotong University, Beijing 100044, China 2 Beijing Engineering Research Center of EMC and GNSS Technology for Rail Transportation, Beijing 100044, China;
[email protected] 3 School of Computer and Information Technology, Beijing Jiaotong University, Beijing 100044, China;
[email protected] 4 Vehicle and Equipment Technology Department, Beijing Subway Operation Technology Centre, Beijing 100044, China;
[email protected] * Correspondence:
[email protected] Received: 14 February 2020; Accepted: 20 April 2020; Published: 24 April 2020 Abstract: Energy conservation is attracting more attention to achieve a reduced lifecycle system cost level while enabling environmentally friendly characteristics. Conventional research mainly concentrates on energy-saving speed profiles, where the energy level evaluation of the timetable is usually considered separately. This paper integrates the train driving control optimization and the timetable characteristics by analyzing the achievable tractive energy conservation performance and the corresponding boundaries. A calculation method for energy efficient driving control solution is proposed based on the Bacterial Foraging Optimization (BFO) strategy, which is utilized to carry out batch processing with timetable. A boundary identification solution is proposed to detect the range of energy conservation capability by considering the relationships with average interstation speed and the passenger volume condition. A case study is presented using practical data of Beijing Metro Batong Line and two timetable schemes. The results illustrate that the proposed optimized energy efficient driving control approach is capable of saving tractive energy in comparison with the conventional traction calculation-based train operation solution.