Reliability Analysis of Modular Multilevel Co-Phase Traction Power Supply System with PV and HESS

The reliable operation of the Modular Multilevel Co-Phase Power Supply Device (MM-CPD), as a key component of the Co-Phase Traction Power Supply System (CTPSS), is of paramount importance. However, the access of photovoltaic (PV) and hybrid energy storage systems (HESS) can change the port current of the MM-CPD and affect its reliability. Therefore, firstly, a day-ahead optimization model of the CTPSS is developed to minimize the traction substation's daily operating cost, and the compensation current of each phase of the MM-CPD is determined. Secondly, the reliability calculation model for MM-CPD is established according to the physical failure mechanism and reliability prediction manual. Finally, the impact of PV and HESS access on the reliability of the MM-CPD is analyzed with actual traction load data as an example, and its best redundancy configurations are determined to maximize the reliability of the device.