With the rapid construction of urban rail transit, the problems such as the low utilization rate of regenerative braking energy have become increasingly prominent. The energy storage system is one of the effective ways to solve the utilization problem of regenerative energy in urban rail, and its reasonable control can accelerate its response speed and improve the stability of urban transit systems. First, aimed at the hybrid energy storage systems of urban rail transit, the characteristics of vehicle-mounted and ground-mounted energy storage systems including their safety, flexibility, transmission loss and energy saving efficiency are analyzed. Second, with the combination of the characteristics of energy storage media, four main energy storage approaches (i.e., battery, flywheel, supercapacitor and hybrid energy storage) for the vehicle-mounted and ground-mounted energy storage systems are summarized separately. On this basis, five control strategies for hybrid energy storage systems are elaborated and analyzed from multiple perspectives, such as their control modes and application statuses. Finally, the key technologies of control strategies for urban rail hybrid energy storage systems are summed up, and the development direction in the future is also projected.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |