Fig.1

Diagram of circuit topology of composite traction power supply system

Tab.1

Comparison of technical index of energy storage device

Fig.2

System operating condition

Fig.3

Static stability domain under reactive power constraints[11]

Fig.4

Output connection of each “source” end of composite traction power supply system

Fig.5

Li-ion battery charge state-system operating conditions-system load demand principle of composite traction power supply system with day-ahead dispatch

Fig.6

Relationship between system scheduling objectives

Fig.7

Priority of system constraints

Fig.8

Range of power constraints at the bottom of the system

Fig.9

Selection principle of converter capacity[26]

Fig.10

Charge-discharge curve of lithium battery

Tab.2

Health status classification of lithium batteries

Fig.11

Variation of system three-phase voltage unbalance degree and PV permeability with system load demand and PV output

Fig.12

Variation of reactive power reserve and PV permeability with system load demand and PV output

Fig.13

Operating status of composite traction power supply system

Fig.14

Single-day traction substation power and photovoltaic generation

Fig.15

Daily operation status of composite traction power supply system before optimization

Fig.16

New energy side output of converter of compound traction power supply system before optimization

Tab.3

Comparison of average one-hour system performance before and after daily system scheduling

Fig.17

Comparison of system performance of three scheduling schemes

Fig.18

Daily operation status of composite traction power supply system after optimization

Fig.19

Comprehensive comparison of traction power supply system

Fig.20

Comparison of carbon emission and economic benefit before and after dispatching